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Bearing News • Issue 3
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What’s Rolling What’s Rolling...
TIMKEN® Pedestal Bearing Strengthens Swiss Mine-Clearance Equipment
Company Donates 20 Bearing Units To The Digger Foundation
Proven To Be Better Thanks To X-Life – Schaeffler Optimizes Its Product Range
Best Practices for BEARING PROTECTION VFD-Induced Electrical Bearing Damage Can Be Prevented, Not Just Repaired.
MESYS Releases New Version Of Shaft And Rolling Bearing Calculation Software
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Interview: The Samurai Of The Bearing Industry Is Forging His New Katana: The Spherical Roller Bearing With `The Largest Load Rating In The World`
Understanding The Root Causes Of Axial Cracking In Wind Turbine Gearbox Bearings
ZKL Expands Its Assortment Of Roller Bearings As A Part Of Its Production Modernization In Klášterec Nad Ohří
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g... TOP 10 TIPS For Bearing Reliability by Mr. Per Arnold Elgqvist
Key Considerations For Designers Looking At Bearing Systems With Linear Axes by FESTO
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Case Study: Monitoring Of A Paper Rolling Cylinder With WI-CARE Wireless Vibration And Temperature Condition Monitoring System
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Case Study:
THE BEARING OF THE
FUTURE
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a study by Kurt Bauwens and Marc Grunewald
Interview: The Perfect Bond Between Bearings And Plastic
How NN is Driving The Future Of Bearing Components
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What Happened in the
Bearing Industry Second Half of
2014 Solution:
Elimination Of False Brinelling In Roller Element Bearings
A COMPARISON STUDY
FOR BEARING MANUFACTURING
CHINA INDIA VS
Managing Machinery’s Silent Killer by Ian Knight
Full Line of High Precision Rotary Stroke Bearings from Mahr Federal
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Solution: RON-Centric, The Most Effective Grinding Technology For Bearing Industry
Research: TORQUE MONITORING The Secret Weapon
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146 Bearing News • Issue 3
TIMKEN PEDESTAL BEARING STRENGTHENS SWISS MINE-CLEARANCE EQUIPMENT ®
Company donates 20 bearing units to the Digger Foundation In a current test at the Swedish EOD and Demining Centre/ Swedec, the Digger exploded 450 antipersonnel mines and three anti-tank mines with up to 8 kg of TNT and the Timken® bearings continued to function flawlessly.
The Timken Company is assisting humanitarian mine-clearance operations in war-torn areas by donating 20 Timken® spherical roller bearing housed units to the Digger Foundation in Switzerland. The nonprofit organization will install the Timken bearings on its Digger D250 mine-clearance machines. Timken appreciates and supports the creativity of Digger in finding professional solutions to save lives and limbs through partnerships with commercial donors. The high-performance housed units contain Timken Page: 10
spherical roller bearings (75 mm inner bore) with nitrided steel cages in a solid, cast-steel housing and special labyrinth seals. Reliable performance, easy assembly and extremely low-maintenance make these units ideal for use with the Digger D250. They help keep the machine’s powerful tiller in position. The tiller reaches a top speed of 450 revolutions per minute and crushes the ground up to a depth of 25 centimeters (nearly 10 inches), causing buried mines to explode. The housing and bearings must withstand these explosions as well as other demands of the application. Bearing News • Issue 3
The Digger D250, with its rapidly turning tiller, crushes the soil and explodes the anti-personnel mines and anti-tank mines.
“The pedestal bearings from another manufacturer that we had previously installed could not withstand the enormous stresses from the antitank mines, since the bearing housing was made from hollow cast iron,” explained Thomas Dalla Piazza, chief engineer at Digger. “Also the
bearing seals were not well-suited to the special environmental conditions under which our mine clearance equipment is used. In contrast, we have had excellent experience with the Timken bearings because their labyrinth seals almost completely protect against any penetrating dirt and dust.”
The 12-ton Digger D250 mine-clearance machine is built-to-order in three to four months. To ensure the operator’s safety, the vehicle is remotely controlled from a distance of up to 500 meters (about a third of a mile).
Hinterreiter, senior sales engineer at Timken. “Our spherical roller housed unit bearings have proved themselves in one of the hardest tests possible - at the Swedish EOD (explosive ordnance disposal) and Demining Centre/Swedec. The Digger exploded 450 anti-personnel mines and three antitank mines with up to 8 kilograms (17.6 pounds) of TNT – and the bearings continue to function flawlessly.”
“I am proud to work for a company that is willing to contribute its expertise and products to the noble efforts of the Digger Foundation,” said Michael
About Digger The Digger Foundation (www.digger.ch) is a nonprofit organization with its head office in Tavannes in the Bernese Jura mountains, whose charitable status is recognized in Switzerland. It promotes technological aid projects in the field of humanitarian mine clearance.
They keep the Digger running (left to right): Pierre Glauser (Digger/ After-Sales Service), Michael Hinterreiter (Timken/ Senior Sales Engineer), Thomas Dalla Piazza (Digger/ Chief Engineer) and Frédéric Razakarivony (Digger/ Customer Support).
It develops, produces and distributes mine clearance equipment under the name of DIGGER DTR, which stands for Swiss expertise in terms of the industry standard and technology. The machines support the
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mine clearance operators and make their work more efficient, less dangerous and more cost-effective. Digger has a track record of successful deployments in the Sudan and South Sudan, Chad, Senegal, Mozambique, Benin, Mali, Croatia, Macedonia and Bosnia.
The high-performance spherical roller bearings of the Timken bearing units (left photo) are installed in a solid cast housing that withstands the extreme stresses when the Digger is used. The previously installed, hollow bearing units from another manufacturer (right photo, left bearing) broke prematurely and had to be replaced frequently.
About The Timken Company The Timken Company (NYSE: TKR; www.timken.
Timken today applies its deep knowledge of
transmission across the broad spectrum of bearings and related systems to improve the reliability and efficiency of machinery and equipment all around the world. Known for its quality products and collaborative technical sales model, Timken posted $3 billion in sales in 2013 (excluding Steel business sales). With approximately 17,000 people operating from 28 countries, Timken makes the world more productive and keeps industry in motion.
metallurgy, tribology and power
Photos: The Timken Company & Digger Foundation
com) engineers, manufactures and markets TimkenÂŽ bearings, transmissions, gearboxes, chain, and related products, and offers a spectrum of power system rebuild and repair services around the world. The leading authority on tapered roller bearings.
What Happened in the
Bearing Industry Second Half of
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Bearing News • Issue 3
Proven to be better thanks to X-life – Schaeffler optimizes its product range
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INCREASED PERFORMANCE FOR ROLLING BEARINGS FROM THE AND BRANDS
X-life is the seal of quality for particularly high-performance products from the INA and FAG brands.
Rolling and plain bearings are extremely important for the function, cost-effectiveness and reliability of a wide range of industrial applications. Their consistent continuous development offers considerable potential that can be used to support higher loads, increase operating life, and improve performance. For more than ten years now, X-life has been the seal of quality for particularly highperformance products from the INA and FAG brands. X-life products are characterized by significantly higher dynamic load ratings than previous standard products. The catalog range is continuously being expanded through the addition of new and performance-optimized X-life bearings that allow customers’ requirements to be fulfilled and the overall efficiency of machines and equipment to be increased. More and more catalog products are thus being replaced by their X-life versions.
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Over the last few decades, the ongoing technical development of rolling bearings (left to right: Ball, tapered roller, and needle roller bearings) has led to a significant increase in their dynamic load ratings.
Optimized design that improves overall cost-effectiveness Under the same operating conditions, the operating life of X-life bearings is significantly longer or, alternatively, higher loads can be applied while maintaining the same rating life values. These state-of-the-art manufacturing technologies enable a better and more uniform surface over the whole contact zone between the rolling elements and
Bearing News • Issue 3
raceway. The internal construction is designed for optimum functionality using state-of-the-art analysis and evaluation methods which ensures optimized contact surface geometry and more even internal load distribution inside the bearing. As a result, there is a reduction in the stress conditions present on the rolling elements and mating track under identical load. This produces a higher dynamic load rating, longer nominal rating life, less friction, lower bearing temperatures as well as a reduction in the strain placed on the lubricant.
Efficient gearbox bearing solutions for agricultural machinery: FAG tapered roller bearings in X-life quality Thanks to their innovative internal design, FAG tapered roller bearings in X-life quality are an efficient bearing variant for pinion shaft bearing supports in tractor transmissions that is particularly suitable for the highest load requirements. Specially machined raceway, roller surfaces and optimized contact geometry between the rolling element end face and inner ring rib allows power loss to be reduced by up to 50%.
INA radial insert ball bearings and housing units: Due to the spherical outside surface of the bearing outer ring and the concave housing bore, housing units can compensate for static shaft misalignments. FAG tapered roller bearing in X-life quality: Optimized contact geometry between the rolling element end face and inner ring rib allows power loss to be significantly reduced.
Tests have confirmed that optimizing bearing positions with X-life bearings allows the overall cost-effectiveness of the relevant application to be improved. The hydraulic systems used in wheel loader travel drives with a power transfer unit, hydraulic pumps, motors, and innumerable rolling and plain bearing positions are one example: The overall efficiency of this application can be increased by up to two percent. For a wheel loader with 140 kW drive power, this means a total saving of around 9 kW. In an application with 1,000 wheel loaders operated for around eight hours a day, this gives an annual savings potential of approximately 26,000 MWh, in other words a financial saving of around five million Euros and a CO2 saving of around 16,000 tons. In addition, optimization using X-life bearings ultimately means that the hydraulic pumps and motors that are used can be made a size smaller.Â
The improved surfaces allow an elastohydrodynamic lubricant film to be formed more quickly at low speeds during the start-up process and in field operation, which means that wear and friction - and thus the generation of high temperatures - can be reduced. Aforementioned design features not only save fuel but also reduce the aging of the lubricant at the same time. The improved surfaces in the rolling contact and the use of higher-quality materials increase the dynamic load carrying capacity up to 20%, which in turn allows the operating life to be extended up to 70%. The contact geometry between the rollers and the raceway (so-called profiling) has been revised and counteracts harmful edge pressure, plastification in the rolling contact in the event of shock loads and severe shaft tilting in the full load range (e.g. during field operation). This protects the bearings and thus the machine from premature failure. FAG tapered roller bearings in X-life quality therefore increase the efficiency, durability, and reliability of
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gearboxes in mobile driven machines and make a significant contribution towards reducing their lifecycle costs. With FAG X-life tapered roller bearings, it is also possible to downsize tractor gearboxes while maintaining or even increasing their performance, thus achieving decisive advantages in terms of costs and competitiveness.
INA radial insert ball bearings and housing units in X-life quality: For a longer bearing life Thanks to X-life quality, radial insert ball bearings and housing units for applications in agriculture, the food processing and packaging industry, and in textile machines also benefit from a 15% increase in bearing life, an expanded application temperature range of -40 °C to 180 °C, and a high level of anticorrosion protection through the use of Corrotect® N coating. An improved locking collar design also means higher clamping forces and thus secure seating on the shaft, thanks to optimized geometry and improved material properties. Reliable seals keep the high-quality bearing grease inside the bearing and prevent the ingress of contamination and moisture. This increases the durability of the bearing and thus extends the operating life of the machine.
The performance increase offered by FAG radial spherical roller bearings in X-life quality is achieved through a new bearing design with a floating central rib and an optimization in the number and dimensions of the rolling elements.
FAG axial and radial spherical roller bearings in X-life quality FAG axial and radial spherical roller bearings in X-life quality are characterized by increased robustness, load carrying capacity, lower friction levels, and greater efficiency in addition to a longer rating and operating life. They are used where very high loads have to be supported and shaft deflections or bearing seat misalignments have to be compensated. The design measures means that on average, FAG radial spherical roller bearings have a 50% higher limiting speed and allow the dynamic load rating to be increased by 15% and the nominal rating life by 60%. Thanks to the design of the rollers which is characterized by an enlarged load-bearing contact surface. At the same time, however, the convex form of the roller end faces ensures a low-friction contact between the rollers and the rib.
INA axial angular contact ball bearings in X-life quality for screw drives are sealed using lip seals or minimum gap seals on both sides of the bearing as standard (here: ZKLN).
The performance increase offered by FAG radial spherical roller bearings in X-life quality is achieved through a new bearing design with a floating central rib and an optimization in the number and dimensions of the rolling elements.
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Improved performance offered by FAG axial spherical roller bearings was made possible by changes to their geometry that increase the load rating, such as longer rollers and larger roller diameters. The rolling partners’improved surfaces ensure that a lubricant film with an even higher load carrying capacity is formed, while improved osculation conditions and additional profiling
Bearing News • Issue 3
optimize the rolling contact. This increases the dynamic load rating by 30%, reduces friction and, with an increase of 240%, more than doubles the rating life.
price-performance ratio. INA -D machined needle roller bearings:
Efficiency with downsizing
Bearings for screw drives – significantly higher performance thanks to X-life quality In addition to reducing energy consumption, the technical optimization using X-life increases the dynamic load rating which, at approximately 10%, is significantly higher than the values achieved by previous bearing designs. This in turn increases the nominal operating life by up to 33%. As a result, the axial angular contact ball bearings have a longer operating life under the same operating conditions. Alternatively, the bearing support can be subjected to correspondingly higher loads while maintaining the same operating life. Design engineers thus have additional options for designing the bearing support.
The ZKLF series features fixing holes in the outer ring to allow it to be easily screwed to the adjacent construction.
In addition to the improvements made to the surfaces, the bearing ring material also undergoes a special heat treatment process. This makes the raceways of the inner and outer rings more resistant to solid particles and mixed friction. This in turn extends the operating life of the lubricating grease, as the strain placed on the lubricant is reduced. This heat treatment measure thus means that the operating life of bearings in X-life quality is significantly longer compared to that of standard bearings and competitors’bearings. The significant improvement in the performance of the bearing support increases its overall cost-effectiveness, which means the customer benefits from a better
INA’s -D machined needle roller bearings in X-life quality feature a newly developed, profiled steel cage produced by optimized forming methods that allows a significantly higher load carrying capacity to be achieved. The cage is designed in such a way that the number of needle rollers and the needle roller length can be increased while maintaining the same bearing dimensions.
INA’s -D needle roller bearings in X-life quality feature a newly developed, profiled steel cage produced by optimized forming methods that allows a significantly higher load carrying capacity to be achieved. The cage is designed in such a way that the number of needle rollers and the needle roller length can be increased while maintaining the same bearing dimensions. The larger number of rolling elements and the increase in their loadbearing length means that the load ratings of new -D needle roller bearings in X-life quality are up to 25% higher. This means that bearings installed in the same mounting space can be subjected to significantly higher loads. Viewed another way, the new -D needle roller bearings in X-life quality open up new design options for downsizing, i.e. a reduction in the size of machines and units while maintaining the same performance. For example: The X-life needle roller bearing NK20/16-D with a bore diameter of 20 mm and a width of 16 mm corresponds to the existing X-life needle roller bearing NK26/16 with a bore diameter of 26 mm in terms of load carry capacity. If the new bearing is used for downsizing, the section height of the bearing is reduced by 15%, the weight by 20% and the friction by 30% while maintaining the same load carrying capacity.
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Best Practices for
BEARING PROTECTION End users of inverter-driven motors have every right to expect uptime and reliability. After all, VFD-induced electrical bearing damage can be prevented, not just repaired. When bearings fail, proper repair practices can fix the problem for good, but value-added services such as inspection, testing, and analysis can prevent the need for repairs in the first place. Motor shaft grounding rings such as those offered by AEGIS® can be installed during motor repairs or on new motors before they are put into service.
Perhaps someday all motors will be built so well that there will be no more electrical bearing damage. Until that day comes, motor repair shops will continue to replace bearings eroded by voltages induced by variable frequency drives (VFDs, commonly known as inverters). And if the customer has to send the same motor back for new bearings again in six months, s/he is likely to develop serious doubts about the shop’s competence. On the other hand, a repair shop that fixes a motor’s bearing problem properly only has to do it once, and is therefore more likely to earn customer loyalty. Better yet, a shop that offers the latest diagnostic services (vibration analysis, thermography, shaft-voltage testing, etc.) can show a customer how the right preventive measures can prevent electrical bearing damage or nip it in the bud. Working at the customer’s plant, on either a brand new motor prior to its installation or on a motor already in service, personnel who know what they are doing can now protect bearings for the life of the motor. This is what we mean by “best practices.”
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Figure 1 The bearings of VFD-driven motors can be damaged by currents from three sources: capacitive induced shaft voltage (A), high-frequency flux produced by common-mode voltage (B), and sinusoidal voltage (C).
Damage By now it is widely understood that induced shaft voltages discharge through the bearings of many VFD-controlled, alternating-current (AC) motors (See Figure 1). The high switching frequencies of today’s VFDs produce parasitic capacitance
Bearing News • Issue 3
Figure 3 In a process called fluting, pits form washboard-like ridges on a bearing race wall — ridges that cause still more noise and vibration and accelerate bearing failure.
Figure 2 Voltages arcing through the bearings of VFD-driven motors create thousands of pits, which cause increased friction and noise and the potential for costly unplanned downtime as bearing grease deteriorates.
between a motor’s stator and rotor. Once the resulting shaft voltages reach a level sufficient to overcome the dielectric properties of the bearing grease, they discharge along the path of least resistance — typically through the bearings (See Figure 2). During virtually every VFD switching
cycle, induced shaft voltage discharges from the motor shaft to the frame via the bearings, leaving a tiny pit (usually 5-10 microns in diameter) in the bearing race. These discharges are so frequent (millions per hour) that — through the process of electricaldischarge machining — they create millions of fusion craters, or pits. Before long, the entire bearing race can become marked with countless pits known as frosting. A phenomenon known as fluting, which shapes the frosting into washboard-like ridges
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across the bearing race, may occur as well (See Figure 3). Fluting can cause noise, vibration, increased friction, and catastrophic bearing failure. As the bearings degrade, high temperatures can cause bearing grease to burn, degrade, and fail, causing decreased bearing life and premature failure. The arcing blasts tiny particles of metal from the race wall, and these contaminate the grease, intensifying abrasion. Too often, the end result is costly, unplanned downtime. Failure rates vary widely, depending on many factors, but evidence suggests that a significant portion of failures occur only 3 to 12 months after system startup. Because many of today’s motors have sealed bearings to keep out dirt and other contaminants, electrical damage has become the most common cause of bearing failure in AC motors with VFDs.
Inspection
Figure 4 The best grounding rings are lined with flexible, conductive microfibers that completely surround the motor shaft.
Cutting and carefully inspecting the bearings of motors needing repair will often provide information that can be used to prevent a recurrence of the problem. Following established safety precautions, repair shop technicians should: 1. Inspect the bearing cavity, retaining a sample of the lubricant in case further analysis is warranted to detect contaminants, signs of excessive heat, hardening or blackening of grease, or grease that has escaped the bearing. 2. Cut the outer race in half. 3. Inspect the grease inside more closely, again searching for signs of contamination. 4. Clean the bearing’s components with a solvent. 5. With a microscope, inspect the race walls for electrical pitting/frosting/fluting.
Grounding If inspection of the old bearing indicates electrical damage, the best way to protect replacement bearings is to install a shaft grounding ring that has a full 360 degrees of circumferential conductive microfibers touching the motor shaft. Such a ring will conduct harmful shaft voltages away from the bearings and safely to ground. With a ring installed, voltage will travel from the motor shaft, through the ring’s conductive microfibers, to its housing, then through the motor’s housing to ground (See Figures 4 and 5).
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Figure 5 A channel locks the ring’s conductive microfibers in place around the motor shaft and helps protect them from excessive dirt, oil, and other contaminants.
All paths must be conductive, so paint on the motor’s faceplate must be removed. Likewise, the motor’s shaft must be clean down to bare metal, free of any coatings (See Figure 6). Depending on its condition, the shaft may require scrubbing with an emery cloth or a similar material. Even when the shaft appears clean, wiping it with
Bearing News • Issue 3
Installation Variations Most of the recommendations above also pertain to grounding rings mounted to a motor’s housing with conductive epoxy instead of screws, split rings designed to slip around an in-service motor’s shaft instead of over its end, larger rings designed for higher voltage motors and generators, and rings press fitted, bolted, or bonded (with conductive epoxy) into a bearing retainer or custom bracket inside a motor’s housing. Figure 6 Prior to installation of a grounding ring, the motor shaft must be cleaned down to bare metal, free of any paint or other nonconductive material.
a nonpetroleum-based solvent will remove unseen residues. After cleaning, the conductivity of the shaft should be checked with an ohm meter. If the reading at the portion of the shaft that will contact the ring’s microfibers is higher than two ohms, the shaft should be cleaned again. A grounding ring should never operate over a shaft keyway, which has sharp edges and could reduce conductivity. On some motors, the dimensions of the spacer and mounting screws can sometimes be adjusted/changed to avoid a keyway. If this is not feasible, the portion of the keyway that will contact the ring’s microfibers should be filled with epoxy putty. Conductivity should be further enhanced by lightly but evenly coating with colloidal silver any portion of the shaft that will contact the ring’s microfibers. This will also help retard corrosion. Threadlocking gels and liquids other than conductive epoxy are not recommended for the screws that mount the ring to the motor, as they might compromise the conductive path to ground. The ring should be centered on the motor shaft so that its microfibers contact the shaft evenly. After installation, testing with an ohm meter is again recommended. The best method is to place one probe on the ring and one on the motor frame. (The motor and drive must be grounded to common-earth ground in accordance with applicable standards.) For environments where the motor will be exposed to excessive amounts of dirt, dust, or otherdebris, it may be necessary to protect the ring’s fibers with an o-ring or v-slinger or install the ring inside the motor’s housing. Bearing isolators with built-in circumferential grounding rings are also available.
For internal installations, an additional machined spacer can keep the ring farther away from the bearing grease cavity. Metal-to-metal contact is still essential, of course, so a bearing retainer must be free of any coatings or other nonconductive material where it will touch the ring. For horizontally or vertically mounted motors with horsepower of 100 (75 kW) or less and single-row radial ball bearings on both ends, a shaft grounding ring can be installed on either end. For horizontally mounted motors with horsepower greater than 100 and single-row radial ball bearings on both ends, the bearing housing at the nondrive end must be electrically isolated to disrupt circulating currents. Options for achieving such isolation include insulated sleeves, nonconductive coatings, ceramic bearings, or hybrid bearings. The grounding ring should be installed at the drive end. For any motor in which the bearings at both ends are already insulated, the drive end is preferred for the installation of a grounding ring, to protect bearings in attached equipment such as a gearbox, pump, fan, or encoder. For any motor with cylindrical roller, Babbitt, or sleeve bearings, the end with such bearings should be electrically isolated, and the grounding ring should be installed at the opposite end.
Testing and Analysis Measuring shaft voltage on a VFD-driven motor provides valuable information for determining whether or not there is a risk of electrical bearing damage. The best time to take such measurements is during the start-up of a new or recently repaired motor. Every motor has its own unique parameters. Combined with vibration analysis, thermography, or other diagnostic services, results (including saved oscilloscope-screen images) can be presented in a report to the customer. Results should also be used in developing preventive and predictive Page: 25
Figure 7 The six-step (or square) oscilloscope waveform shown here is typical of motors exhibiting maximum peak-topeak shaft voltages, but no discharges through the bearings.
Figure 8 The above waveform shows the rapid voltage discharge through the motor’s bearings that occurs when shaft voltages reach a level where they overcome the dielectric properties of bearing grease.
Figure 9 The continuous discharge pattern indicated by the relatively low-voltage waveform on this oscilloscope screen is the result of the bearing lubrication becoming conductive.
Figure 10 With an effective, properly installed grounding ring to protect its bearings, a motor produces an oscilloscope waveform like this one, with peak-to-peak discharges of only two or three volts.
maintenance programs.
By Adam Willwerth
Shaft voltages are easily measured (using appropriate safety procedures) by touching an oscilloscope probe to the shaft while the motor is running. The best probe will have a tip of high-density conductive microfibers to ensure continuous contact with the rotating shaft. A portable oscilloscope with a bandwidth of at least 100 MHz should deliver accurate waveform measurements (See Figures 7 through 10). Probe/ oscilloscope kits are available.
Adam Willwerth, Sales and Marketing Manager for Electro Static Technology, has extensive experience in industrial product development and 22 years as Maintenance Manager with the U.S. Navy. He is named on four patent applications pertaining to conductive microfiber shaft grounding technology and has presented seminars on the subject of bearing current mitigation at professional conferences in the U.S. and Europe. Willwerth holds a Master of Business Administration degree from Southern New Hampshire University and a Bachelor of Science degree in management from the University of Maryland.
Just as shaft voltage measurements can show that a motor’s bearings are in danger of electrical damage, they can confirm that a shaft grounding ring is working. If a proven ring has been properly installed, typical discharge voltage peaks should be less than 10 volts, depending on the motor.
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For a 36-page handbook on the practices summarized in the above article, contact Electro Static Technology, 31 Winterbrook Road, Mechanic Falls, ME 04256-5724, TEL: (207) 998-5140 or download on http://est-aegis.com/bearing/bn1/ index2.htm Bearing News • Issue 3
mesys
Releases New Version of Shaft and Rolling Bearing Calculation Software The MESYS Rolling bearing calculation allows the calculation of bearing load distribution and bearing life according to ISO/TS 16281. It is available as standalone application or integrated in a shaft system calculation with additional possibilities like modal analysis, shaft strength calculation according to DIN 743 or interfaces to gear calculation programs. New features have been added for the release 08/2014. Spanish language is now available in addition to English, German, French and Korean for both software and report; reports can now be generated in formats like DOCX, DOC and ODT in addition to PDF format and table legends are added.
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Bearing News • Issue 3
Main changes in bearing calculation are: • Additional bearings types like axial spherical roller bearings, barrel roller bearings and double row axial angular contact bearing are now also supported. In total, 22 bearing types are available now. • Result data for rolling element loads can now be exported in table formats like XLSX, XLS or CSV. • Static load rating diagram for permissible radial load over axial load in addition to moment load over axial load. • Diagrams for single load cases of load spectra. • Additional outputs in parameter variations like ball advance.
shapes in modal analysis either in 2D or as 3D animation. • Improvements in 3D view, now also the contact ellipse/line load is shown for rolling element of a bearing. • Tooth flank modification for optimum gear contact can be considered independently for each flank. The modifications are taken into account in the calculation of line loads. Most users of the bearing calculation software are bearing manufacturers, others use the shaft system calculation for gearbox design and modal analysis. The software is currently used in 20 countries over four continents. A demo version is available at www.mesys.ch/?page_ id=157&lang=en
• All results in the bearing calculation are now available in US units. • New graphic for load distribution 3D, including contact ellipse or line load for rolling bearings.
Main changes in the shaft calculation are: • Worm and worm gear as force elements, and worm gear connections for shaft systems. • Temperature gradient within the shaft. • A coupled housing stiffness matrix is available now. Multiple matrices can be defined in either local or global coordinate systems. • Simultaneous representation of multiple mode Page: 29
NN, Inc. is a leading global manufacturer of high-performance precision components. • Precision Bearing Components • Autocam Precision Components • Precision Plastic and Rubber Components NN supplies components to a variety of markets, and our global manufacturing footprint enables us to serve customers around the world. We deliver precision solutions where they are needed with uncompromising quality and delivery standards, while focusing on R&D and innovations for tomorrow’s technologies. www.nninc.com
Mr. Mohammad Rajabi General Manager of Bearing Division at Nachi Europe GmbH
The Samurai of the Bearing Industry is forging his new Katana: The Spherical Roller Bearing with `The Largest Load Rating in the World`
Page: 31
A TRADITION OF PRODUCTION Fulfilling aspirations as a manufacturing company
Mr. Mohammad Rajabi
General Manager of Bearing Division at Nachi Europe GmbH
The forging of a Japanese blade in ancient times took many weeks, and was considered a sacred art. Blades were often forged with different profiles, different blade thicknesses, and varying amounts of grind. The steel used is known as tamahagane, or “jewel steel”. Nachi Fujikoshi is an industry leader in Machining, Robots, Industrial Components and Materials; the perfect combination between industries, knowledge and tradition to produce the spherical roller bearing with ‘The Largest Load Rating in the World’. We tried to learn more about the Bearings of Nachi Fujikoshi during an interview with Mr. Mohammad Rajabi, General Manager of bearing division at Nachi Europe GmbH, located in Krefeld, Germany.
What is the mission of Nachi Fujikoshi? Our mission is to contribute to the progress of the world of product manufacturing.
Can you give us an overview of Nachi products? We have 4 major product groups existing out of Machining products, Robots, Components and Materials. All of our product divisions are connected and synchronized with each other in order to produce the best and highest quality products. Some of our Machining products are Cutting Tools, Forming Tools, Broaches, Machine Tools, Precision Machinery and Machining Systems. Our Components division is responsible for Bearings, Hydraulic Equipment and Automotive Hydraulics. The Components division is working very closely with the Materials division who is in charge for Special Steels, Coatings and Industrial Furnaces.
What is your company sales by turnover, product groups and markets? Our company turnover is $1.9 billion. The bearing product group is worth for 37% and the automotive market for 53% of all our sales.
When did Nachi Fujikoshi start the production of bearings and what was the evolution in the company? Nachi Fujikoshi was founded in Toyama City Japan by the founder, Mr. Kohki Imura in 1928. The company was founded with the aim of becoming a domestic manufacturer of cutting tools and machine tools in the trend towards industrial modernization. This aim was fulfilled very fast and the company’s business activities expanded on high speed during the first 20 years after establishment.
The production of bearings started in 1939 with the set up and apply grinding and heat treatment technologies in our production lines. We produced firstly ball bearings and spherical roller bearings with high-quality materials. In the 1950’s the bearing production line was expanded with special-purpose bearings and railway bearings. After the development of highquality bearing steel by our Special Steel division in early 1960’s, we started the production line for Jet engine bearings. This process was followed by the development of hot press forming technology for inner/outer rings and resulted with the production Page: 33
of Triple-race bearings and bearing for printing presses. In the 1980’s a new program was started with our Steel Section for the production of long-life bearings. During this program the automotive air condition bearings and roller bearings for synchronized joints came into production. We started the production of 4-point contact ball bearings in 1993. After the year 1973 the production of bearings was internationalized by establishing factories in Brazil, USA, Thailand, China, Taiwan and India for the production of sealed support bearings, Quest ball bearings series and EX-V rollers bearing series.
What is the difference of Nachi from the other producers? We achieved our current position on the world markets because of the great importance we attach to our customers demand. All our products are produced according to the international standards and with high precision and quality. Our professional teams from the production to the sales are enabling Nachi to be one step ahead in this industry.
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We have a vertical integration at Nachi and are not dependent on external vendors for assuring the quality of our work. All our products are manufactured in our own plants, with our own specially engineered machine tools by using our own tooling. We even make our own steel and heat treat it in furnaces of our own production. This means is that we control every aspect of the manufacturing process. Quality builds on quality, every step of the way. In this way we ensure the quality by maintaining rigorous standards which are continuously monitored and improved. Accountability for quality begins and ends with us. Our customers can trust Nachi products because our reputation is everywhere at the production line.
What do you think about the current market conditions and how does this influence your strategy? The world economy slowed down with the recent global economic crisis. I think that the effect of crisis will change during 2015 and that the economic growth rate will increase a little bit, but anyhow we have to be careful. Countries need to take the necessary measures and make them applicable for a continuous and stable recovery.
Bearing News • Issue 3
Fujikoshi?
We develop our own niche markets for industrial machines with strategic products and use new marketing techniques to bring them on the market. We are also strengthening our current sales infrastructure all around the world and on the emerging markets. This strategy is working well thanks to our strong relation with our local business partners who represent Nachi on their markets.
I believe that our success lies in our company philosophy, which was defined by our founder Mr. Kohki Imura. We have kept and are still keeping the 5 aspects of our Corporate Philosophy as a fundament during our daily work.
Can you give us more information about your Spherical Roller Bearings?
Today’s dream brings a better tomorrow. Creation causes some discord. Improvement is assured by conquering such discord.
Nachi spherical roller bearings are produced to obtain resistance under heavy loads. They were designed with a uniform internal geometry between the raceway and the rollers. The most important is that our Steel Section has developed long life bearing steel which is used for the production of our spherical roller bearings.
Aggressiveness - Tackle your job aggressively.
Thanks to the knowhow on bearing steel, the re is currently a more sensitive and better controlled heat treatment technology for the production of bearings which can operate safely under hard conditions. Standard bearings, lose their size precision over 120°C and the format of the steel starts changing on micro levels. This micro changes cause loss of hardness in the bearings and the steel suffer from loss of working life as it loses the capacity to carry loads. The heat treatment technology used by Nachi on bearings enables the bearing steel to maintain the micro structure and prevents the loss of hardness even under the working conditions in 200°C. This special treatment stops premature break-downs by preventing high temperature changes. Operation under condition of 200°C is a standard for Nachi Spherical Roller Bearings. Beside the internal geometry, steel quality and the high-tech heat treatment process; the size of the rollers used in the spherical roller bearings and the design of the cage structure are also playing an important role by achieving the ‘highest load rating’ available on the market. This result is an achievement of the synergy between our Cutting Tools, Design and Production departments who are involved in the production of the bearing components.
How can you describe the success of Nachi
Creativity - Business withers without creation.
Give priority to difficult assignments and never give up when the job is half done. Globalism - The globe is your market. Win the trust of the people of the world. Supply quality products at reasonable cost. Nurture the competitiveness of your products. Appreciative minds - Always be appreciative of what people around you do for you. Thank your parents for having given birth to you. Thank elders for their guidance. Serve the community in order to reciprocate its hospitality towards you. Human assets - To make the company prosper, is to find and work with the right person for the right job. Quality people are difficult to come by. Be objective. Be health conscious. Be wise. Stick to your words.
What is the mission of Nachi Fujikoshi? Our mission is ‘contributing to the progress of the world of product manufacture’.
What is the mission of Nachi Europe? The mission of Nachi Europe exists out of four R’s: -Right product -Right price -Right time -Right place Nachi Europe is since 1967, here in Germany to serve our European customers with best Technical, Commercial and Logistic services. Page: 35
We keep your world rotating PRĂœFTECHNIK specializes in measurement technology for rotating machinery We offer innovative solutions including products, services, training and support for industrial maintenance across all industries and around the world: condition monitoring, vibration analysis, laser shaft alignment, geometrical measurements, roll alignment, and more.
Find out how we boost uptime
PRĂœFTECHNIK AG Oskar-Messter-Str. 19-21 85737 Ismaning Germany PROVEN QUALITY
Made in Germany Global Presence Qualified Support Quality Service
Tel.: +49 89 99616-0 Fax: +49 89 99616-100 info@pruftechnik.com www.pruftechnik.com
Understanding the Root Causes of Axial Cracking in
Wind Turbine Gearbox Bearings Introduction
Part 1:
Modern Wind turbines are an important piece of our energy mix. Unfortunately, gearbox life issues have impacted their financial payback. Axial cracks in bearing raceways have become the major cause of premature gearbox failures in the latest generation of wind turbines, shortening life to as little as 1-2 years once damage is initiated. Axial crack failures in gearbox bearings are rare in other industries. Why damage is so common in wind turbines is a mystery that is the subject of intense research. The root cause must be understood tosuccessfully find the solution.
Axial Cracks < White Etch Cracks < White Etch Areas < Impact Loading & Rapid Plastic Deformation
This paper is divided into two parts. Part 1 is a review of the latest research on the phenomenon of axial cracking. It discusses how these axial cracks grow from smaller cracks that have a white color when they are sectioned and etched. These White Etch Cracks (WEC) can originate from microscopic super-hard areas that also show up white when sectioned and etched. These areas in which cracks occur are called White Etch Area (WEA) damage. It appears that a threshold of rapid and severe plastic deformation must be exceeded to create these hard microscopic WEA areas. But what event in a wind turbine could cause such rapid and severe loading on the bearings? That is the subject of Part 2. It is based on recent research and field monitoring by the authors that was presented at the NREL GRC in February, 2013, along with additional research and field data generated since that presentation.
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Axial Cracking Axial cracks on inner rings of high speed and intermediate speed bearings have become a leading cause of wind turbine gearbox life problems. See Figs. 1 and 2. Numerous technical papers have been written on axial cracking in the past Fig. 1 A single axial crack that has propagated couple of years, many completely through the inner ring. of which have focused on why this unusual bearing phenomenon is so prevalent in wind turbine gearboxes. Some of these publications are referenced with footnotes and listed at Fig. 2 Multiple axial cracks on the inner ring the end of this paper. in early stages. Wind turbine bearings are selected to meet a 20-year design life, with a low likelihood of failure. Most manufacturers follow Germanischer Lloyd
Bearing News â&#x20AC;˘ Issue 3
(GL) guidelines for gearbox bearings. GL requires that gearbox bearings be analyzed for Rolling Contact Fatigue (RCF) resulting in the calculated life being at least 130,000 hours with a likelihood of failure at less than 10%.6 If wind turbine gearboxes meet these design criteria, how can axial cracking failure rates be so high and often occur within the first or second year of operation? How can it be that a bearing that has been analyzed using wellunderstood and validated methodologies will likely fail much sooner than predicted? The answer lies in the fact that the axial cracking failure mode differs from the classic RCF failure mode. RCF failures are caused by damage to the bearing material that accumulates over time – at well understood rates. The axial cracking failures are relatively recent phenomena and their modes of failure are much less understood. Why does axial cracking failure mode occur in the inner ring of a bearing? This is mainly due to the inner ring being typically mounted to a shaft with an interference fit. The ring is heated during assembly onto the shaft. When the ring cools, it shrinks – holding the ring in place, but also creating tensile stress in the ring that increases the possibilities for axial cracking.6 An axial crack failure of the inner ring can be caused by excessive hoop stresses during installation but this does not appear to be the general case in the wind industry. Microscopic, white-colored areas at the edge of the cracks when the bearings are sectioned and etched are the key indicator that these are not merely standard hoop stress failures. These cracks are termed White Etch Cracks (WEC) and are commonly found in through-hardened bearing races.
White Etch Area (WEA) - Subsurface Microscopic Material Alteration
Fig. 3. A microscopic WEA formation with nano hardness measurements showing a 44% increase in hardness. Courtesy A. Greco et al 1
Detailed failure analysis of axially cracked bearings reveals that the White Etch Areas also appear in subsurface cracks and even in areas where cracks have not yet started. WEA damage is actually a microstructural
alteration of the inner ring material, creating tiny super-hard areas (30 - 50% harder than the surrounding area) 2, 3, 6 just below the raceway surface. These areas act like inclusions in the steel (Fig. 3 shows a microscopic WEA formation with nano hardness measurements). Once an event occurs that initiates the subsurface WEA formations, normal rolling action of the bearing can cause cracks to start at the junction of these inclusion-like areas. The crack will inevitably propagate to the surface and become a White Etch Crack (WEC), which can grow axially across the raceway and prematurely fail the bearing. Many research papers recognize two primary mechanisms for WEA damage: hydrogen-induced WEA and stress-induced WEA. Hydrogen WEA is believed to be driven by corrosion, water contamination, electrical currents and/or aggressive oil additives that can worsen cracks once they appear on the surface. But what events initiate these surface cracks? This paper focuses on understanding the events that can initiate subsurface stress-induced WEA damage and Part 2 will show that these same events could cause surface cracking, as well. This can explain how hydrogen-induced WEA is initiated in the first place. Stress-induced WEA damage in the bearing inner ring must come from an event that can cause the roller to exert high subsurface stresses simultaneously with rapid strain rates. Possible WEA mechanisms mentioned in recent papers include: • Impact Loading – sudden loads that can causehigh stress and strain; • Surface Traction – frictional contact between the rollers and races that produce high surface and subsurface stresses; • Severe Plastic Deformation (SPD) – subsurfacestress high enough to cause microscopic deformation; • Rapid Plastic Deformation (Adiabatic Shear Bands, ASB) – subsurface plastic deformation so rapid that the heat generated cannot be dissipated and thus directly alters the material to cre ate ferrite microstructures. All four of these mechanisms are related and can occur at the same time. For instance, WEA damage can be created in the Lab with ballistic impacts, Page: 39
where all four of these WEA mechanisms have been shown to act simultaneously. When a bullet passes through metal, the impact causes surface traction and severe and rapid plastic deformation, creating Adiabatic Shear Bands (ASB). When the WEA cracks become visible on the inner ring surface, they are termed White Etch Cracks (WEC). When Fig. 4 shows White Etch Cracks (WECs) and White Surface Flaking (WSF) on WEA damage the inner ring of a tapered roller bearing. Evidence suggests that both were initiated by WEA microstructural alterations in the steel subsurface. Courtesy causes flaking A. Greco et al 1 or spalling, it may be termed White Structure Flaking (WSF). This can occur with carborized raceways. See Figs. 1, 2 and 4. Either way, the damage starts with the creation of White Etch Areas.
Impact Loads & Rapid and Severe Plastic Deformation (Adiabatic Shear Bands) An adiabatic shear band (ASB) is an area within a base material that has been transformed by microscopic, localized heating during rapid and severe plastic deformation. Since the 1960s, adiabatic shear bands have been studied extensively because of their importance as a failure mode in areas such as high-speed metal forming and cutting, various types of ballistic impact, as well as vehicle crashes. “Adiabatic” is a thermodynamic term simply meaning an absence of heat transfer – the heat produced is retained in the zone where it is created. These shear bans are usually very narrow, typically .0002 to .020 inches. In steel, these bands are in fact WEA damage where fatigue cracks can initiate. There is a threshold of instantaneous high stress and strain rate where microscopic plastic deformation creates heat so fast that it cannot escape. The subsurface metal momentarily softens and transforms the material as it cools into an altered microstructure. Severe deformation that occurs slowly will let the heat escape and will not produce ASBs or WEA damage. Thus a stamped metal part may show a similar degree of plastic deformation as a bullet hole but because the strain rate is lower, ASBs and WEA damage can be avoided. In bearing material, the heat from the rapid Page: 40
plastic deformation can cause a microstructural transformation of the hardened bearing steel into a sliver of super-hard ferrite that appears white when sectioned and etched, WEA damage. A band of WEA damage is not required to fail the bearing. A single sliver of this WEA damage can act as an inclusion to initiate White Etch Cracks that eventually propagate to the surface and across the bearing raceway surface.6 Bearing manufacturers have continuously improved the life of rollerbearings by improving the purity and quality of the steel used in their products. By minimizing hard inclusions and stringers (elongated carbide or sulfide inclusions), they minimize the potential places where cracks can initiate and propagate. These efforts have achieved an impressive 10-fold increase in bearing life as predicted by the standard Rolling Contact Fatigue (RCF) method used by bearing manufacturers to calculate L10 life.2,6 Unfortunately, all the efforts to make super-clean steel can be wasted by events in a wind turbine’s operation that initiates WEA damage, mimicking inclusions less than .04 inches (1 mm) below the raceway surface. This depth coincides with the depth of maximum shear stresses under the bearing raceway during normal Hertzian loading of the rollers. Also, this is the worst possible location for an inclusionlike impurity to be located, leading to shortened bearing surface fatigue life and axial cracks. Once started, WEA damage can reduce the bearing life to just 1% to 10% of predicted life as calculated with standard rolling contact fatigue formulas.2 This explanation shows how WEA induced axial cracks can cause bearings to fail within one to two years of operation. What events in a wind turbine could create impact loads and rapid plastic deformation significant enough to initiate the WEA damage? Some researchers have concluded that, “A wind turbine exposed to an extreme event, such as a power loss or emergency stop, could produce the localized deformation energy needed for ASB formation”.3
Part 2 Emergency Stops > Transient Torque Reversals > Rapid Bearing Load Zone Reversal > Impact Loads and Rapid Plastic Deformation of Bearing Material Emergency Stops and Other Transient Turbine
Bearing News • Issue 3
Events All the recent papers on bearing axial cracking support impact loading and emergency stops as likely contributors to WEA damage. Wind professionals have long recognized that emergency stops and other sudden stops can put extreme loading into all turbine drive components. Many have even noted a relationship between E-stops and gearbox life. There is a growing awareness that it is the Transient Torque Reversals (TTRs) during these severe stopping events that may be the source of damaging impact loads in gearbox bearings 7. See Figs. 5 and 6. Many types of drive systems in other equipment see severe transient loading and torque reversals without experiencing WEA damage to their bearings. Severe torque loads without reversals, and torque reversals that happen slowly in a controlled manner, would not create rapid plastic deformation in the bearing raceway. Wind turbines are different. Why? Their drive systems are unique in the severity of their torque reversals and the rapidity at which they can happen.
Rapid Torque Reversals What is it about a turbine drivetrain that
Fig. 7 Aligned rollers are in green load zone. Misaligned rollers are 180° opposite and are circled in red. In a TTR, these unaligned rollers are suddenly loaded repeatedly.
causes it to be so susceptible to the rapid and severe torque reversals shown in Figs. 5 and 6? This has to do with the relative rotating masses (inertias) of the blades and the generator rotor, and how they can react against each other within the torsional natural frequency of the drive system. A typical turbine has 80 to 90% of its relative inertia in the blades, with most of the rest of the inertia in the generator rotor. In normal operation, the blades are driving the generator in the positive direction. A grid disconnect, emergency stop or high wind shutdown can trigger rapid aero braking of the blades that will attempt to decelerate the drive system. Most of the aero braking effort goes into decelerating the massive blade inertia, but some of it goes through the drive system to decelerate the generator. This typically causes a torque reversal in the drive system that can result in the inertias of the system winding up and unwinding against each other several times at the torsional natural frequency of the system as it decelerates. Note: the turbines of Figs. 5 and 6 have similar natural frequencies despite their significant size difference. How do these reversals cause impact loading in the bearings?
Rapidly Reversing Bearing Load Zones & Impact Loads on Misaligned Rollers Fig.5 – A Transient Torque Reversal (High Wind) event captured on a 2.0MW wind turbine.
Fig. 6 – A Transient Torque Reversal (High Wind) event on 1.0MW wind turbine.
Impact loads can be damaging to bearings in some other types of equipment and can even cause WEA damage. Rapidly reversing bearing load zones are also known to be very damaging to bearing life. During transient torque reversals every bearing in the gearbox sees a rapid load zone reversal of almost 180° that can cause severe impact loads between the rollers and the raceways. All the cited papers recognize that impact loading could be the source of the stress-induced subsurface WEA damage, and most of the papers name it as a suggested leading candidate. During normal operation, the rollers in the bearings are aligned and rolling at the expected speed while they are in the load zone. As they leave the load
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Blade Dynamics – Not All E-stops are the same… How Emergency Stops with High Winds, Turbulence, and Gusts Can Magnify Torque Reversals and Bearing Impact Loads Pitchable blades allow today’s wind turbines to achieve close to the ideal power curve shown in Fig. 10. Blade pitch control is important to maximizing the energy capture from the wind. In addition, it is critically important as the primary safety braking system for protecting the turbine from damaging wind loads and overspeed in the event of any turbine subsystem failure that prevents continued operation. Fig. 10 also shows the pitch angles of a typical modern turbine. At low wind speeds, the blades start out in a fully feathered position almost 90 degrees to the plane of the rotor swept area. In region II, the blades rotate to almost zero degrees pitch angle to extract the maximum power, capturing close to 50% of the wind’s available power. In region III, the blades are pitched back to protect the turbine from high stresses as it strives to control and maintain full rated power. At cut-out speed, the blades are quickly pitched to provide braking to decelerate the turbine drive system. The Fig. 11 view of the power curve masks the challenge of protecting the turbine from damage during high and turbulent winds. Fig. 14 shows the turbine power curve compared with the wind’s zone, the rollers slow down and can misalign within the tolerance of the cages. As they approach the load zone again, they are gradually brought back into alignment and smoothly accelerate to support the load. In a rapid load zone reversal, the unloaded rollers opposite the normal load zone are suddenly loaded while in this misaligned state. See Fig.7. This rapid loading increases the load concentration of the rollers in the middle of the inner race. See Fig. 8 for highest stress load locations. Although transient torque loads are common to many types of equipment, torque reversals of the magnitude and rapidity shown in Figs. 5 and 6 are unique to wind turbines. In gearboxes with helical gearing, every cylindrical bearing will see high axial loads simultaneous with the radial loads impacting misaligned rollers. See Fig. 9. These rollers may slip axially and damage the raceway surface, shortening bearing life through pitting and Page: 42
Fig. 10 – Typical Power Curve and pitch angles of modern wind turbines
available power. As the winds approach the typical cut-out speed of 25 mps (55 mph), the turbine may use less than 10% of the wind’s available power. The blades must be pitched to the precise angle to effectively spill wind power equal to 10 times the turbine’s rated power and protect the drive from excessive loads. With longer blades, the cut-in speed and the rated power speeds can be achieved at even lower wind speeds – dramatically improving the annual energy output and financial performance projections. But the excess wind power at cut-out speed that must be safely spilled over the edge of the blades may be even greater than 10 times the turbine’s rated power.
spalling. The sliding can also result in scuffing of the raceway causing microscopic cracks Fig. 8 – Image showing the areas in a bearing with the highest stress during a that allow Transient Torque Reversal. subsurface entry of water or aggressive oil additives to initiate hydrogen induced WEA. If the radial impact load is so high that the roller breaks through the oil film, it can create mixed friction sufficient to prevent slipping axially. Axial subsurface stresses will be added to the Hertzian stresses from the radial impact, magnifying the stresses. The strain rate would be magnified, as well. If this exceeds a threshold where WEA microstructural alterations could form, it may explain why WEA damage is common in wind turbine gearboxes and rare in Bearing News • Issue 3
At high wind speeds, the blades are already pitched back in the range of 20-30 degrees to spill most of the wind power. During a grid loss or e-stop, the blades rapidly pitch further to decelerate the turbine. This is when the potential for torque reversals and impact loads to the bearings is the worst. The highest winds tend to occur during stormy weather when wind gusts and turbulence are high and the possibilities for grid loss and e-stops are greatest. High wind shutdowns and e-stops during gusty wind conditions can create a perfect storm for drive system torque reversals and damaging impact loads on the bearings. The worst torque reversals we have recorded occurred at high wind speeds. See Figs. 5 and 6. We are doing additional research and are gathering field data on how severely aerodynamic braking impacts the dynamics of the drivetrain. More to come on this subject.
Fig 11 â&#x20AC;&#x201C; Turbine power curve versus available wind
most other bearing applications. Tapered roller bearings can also be damaged by the effects of load reversals. High speed and intermediate speed bearings typically are not preloaded (due to thermal constraints) and see axial movement and impact loads. The bearing axial cracking issue Fig. 9 â&#x20AC;&#x201C; Image showing the simultaneous radial impact and axial loading of the misaligned roller. did not become a prominent failure mode until the larger megawatt and multi-megawatt sized wind turbines began to dominate the market. The main gearbox failure mode of older, smaller wind turbines was not typically axial cracking. Their failure mode was primarily bearing surface deterioration from pitting and scuffing. Why has axial crackingdeveloped as turbines have grown in size? Fig.12 compares the relative torque magnitude and
the rate of torque change during rapid reversals of three different sized turbine models. High resolution torque monitoring equipment recorded torque reversals that approximated the turbine rated torque at the high speed shaft on ž MW, 1 MW and 2 MW turbines. The torsional natural frequencies of the turbines during braking were all similar with oscillation periods about 0.75 second-per-cycle. The higher torque loads of the larger turbines can be accommodated in the sizing of the bearings but the oil film thickness will not increase.Any roller misalignment can more easily cause high local-contact stress during a torque reversal. The difference in the rate ofincrease of the reverse torque during the torque reversal may be an even bigger issue (comparison rate is noted in Fig. 12), as it directly relates to the strain rate in the raceway as the rollers impact. There is a threshold in rapid plastic deformation (adiabatic shear) where the instantaneous heat created causes the microstructural alteration of the base material. Could the increasing strain rate of larger turbines be exceeding that threshold? Page: 43
During rapid load zone reversals, could the rapidly increasing load on the rollers be creating fast enough plastic deformation to be transforming a microscopic sliver of the bearing steel to a superhard ferrite WEA inclusion? Certainly all the elements for WEA microstructural alterations are present simultaneously for an instant. The torque reversal takes up the gear backlash and rapidly impacts the idling rollers on the unloaded side of the bearing. The misaligned rollers can make the stress concentration and the plastic deformation under the rollers worse and initiate mixed friction contact. Simultaneous reversal of the axial load on the bearing due to the helical gearing causes surface traction and additional stress at the inner raceway subsurface. The resulting high strain rates and plastic deformation can explain the creation of the WEA microstructural transformation. Because the WEA sliver is perfectly placed under the raceway surface, one microscopic sliver would be enough to initiate the WEA damage that would result in an axially cracked failed bearing. All it takes is one moment where the combination of high load and strain rate threshold is exceeded: one severe e-stop, a combination of an e-stop with a wind gust, high wind shutdown, control malfunction, sensor failure, etc. Some researchers have noted that torque reversals can create loads up to 2 ½ to 4 times nominal torque 4. That would be 2 ½ to 4
Fig. 12 – High resolution torque reversal recordings on 3 sizes of wind turbines showing the rate of change in torque. The steeper slope indicates significantly higher strain rates.
times the torque loads shown in Fig. 12. Because the natural frequency is unchanged, the strain rate would be 2 ½ to 4 times higher, as well. Every doubling of the torque magnitude, with the same natural frequency, may effectively quadruple the instantaneous deformation energy that causes WEA damage.
Conclusion Rapid and severe impact loading of the rollers on the bearing raceway cancause stress-induced WEA damage, dramatically shortening the life of bearings and gearboxes. There are three ways to address the problem: 1. Strengthen the system or componentsto reduce the degree of damage by: • Changes in raceway material, processing and coatings; • Changes in bearing type; • Improved lubrication and oil additives; 2. Try to detect the damage and replace the bearings before catastrophic failure by: • More frequent borescoping; • Better conditioning monitoring systems; 3. Solve the root cause by preventing the excess Page: 44
Fig. 13 – Dampening effect of reducing transient torque reversals to 40% of nominal torque.
stress and strain rate from happening by: • The addition of an asymmetric torque limiter;7 Ongoing research should prove the relative value of these solutions to extending bearing life. Some of the solutions proposed may incrementally extend life or prevent catastrophic failures with Bearing News • Issue 3
early detection of the axial cracks. The asymmetric torque limiter actually addresses the root cause – the rapid and severe loading that can initiate the stress-induced WEA damage. Simple frictional slip torque limiters are commonly used to protect wind turbine drive systems from severe torque overloads, such as generator short circuits. No evidence has been ound that a basic torque limiter can provide protection against axial cracking. An asymmetric torque limiter has a much lower slip setting in reverse. Field testing of wind turbines with and without the asymmetric torque limiter has demonstrated its ability to significantly reduce the maximum reverse torque and rate of torque increase, thus reducing maximum stress and strain rate caused by the rollers impacting on the bearing raceway during the torque reversal. This approach would also dampen torsional vibrations to reduce the number of reversals. See Fig. 13. Field data from a 750 KW turbine (Fig 14) shows the effectiveness of the asymmetrical torque control in reducing the maximum reverse torque and the maximum rate of reverse torque increase. Note that both the magnitude of the stress and the maximum strain rate of the rollers impacting the raceway are reduced by over 50%; a 75% reduction of the instantaneous impact and deformation energy. This deformation energy reduction can be achieved on larger turbines in a similar manner with the likely outcome of dramatically reducing the axial cracking. If asymmetric torque control can keep impact loads below the threshold where WEA
Fig. 14 - Comparison of torque reversal magnitude and rate of change for a 750 KW turbine with and without an asymmetrical torque control.
microstructural alterations are initiated, super-hard WEA slivers could never form under the raceway, and axial cracks in gearbox bearings would cease to be a prominent mode of failure affecting the cost of wind turbine energy. References: 1. A Greco, PhD, et al., Bearing Reliability – White Etching Cracks (WEC), Argonne National Laboratory, Energy Systems Division, NREL Gearbox Reliability Collaborative, Feb 4 (2013) 2. M.-H. Evans, White Structure Flaking (WSF) in Wind Turbine Gearbox Bearings: Effects of Butterflies and White Etching Cracks (WECs), Material Science and Technology 28 (2012) 3–22. 3. A. Greco, et al., Material Wear and Fatigue in Wind Turbine Systems, Wear (2013), http://dx.doi.org/10.1016/ j.wear.2013.01.060i 4. Kenred Stadler, Arno Stubenrauch, Premature Bearing Failures in Industrial Gearboxes, SKF GmbH, Gunnar-Wester-Str. 12, 97421 Schweinfurt, Germany 5. J. Rosinski, D. Smurthwaite, Troubleshooting Wind Gearbox Problems, Gear Solutions 8 (2010) 22–33 6. Rob Budny & Robert Errichello, How To Minimize Axial Cracking Failures, North American Windpower, June 2013 7. Jean Van Rensselar, Extending Wind Turbine Gearbox Life, Tribology and Lubrication Technology, May 2013
by Doug Herr and David Heidenreich
THE BEARING OF THE
FUTURE a study by Kurt Bauwens and Marc Grunewald
Page
64 Page: 45
ZKL
E X PA N DS ITS ASSORTMENT OF
ROLLER BEARINGS AS A PART OF ITS
PRODUCTION MODERNIZATION IN
KLÁŠTEREC NAD OHŘÍ
ZKL expands its assortment of roller bearings as a part of its production modernization in Klášterec nad Ohří ZKL Klášterec nad Ohří is accommodating the ever growing demand for roller bearings. That is why the company is adding a brand new innovated line of roller bearings of a higher quality standard (NEW FORCE) to its assortment. The introduction of a new roller bearing line, which represents an investment of more than 100 million crowns, is partially financed from the European Innovation and Property projects. ZKL Klášterec nad Ohří will newly offer its customers almost 50 new types of roller bearings, which can be mainly used in the area of transport devices. ZKL Group has been producing roller bearings for several decades. The objective of the currently planned innovation at the ZKL Klášterec nad Ohří plant is to expand the production of roller bearings of the NEW FORCE design and special, cage-free roller bearings. Apart from that, ZKL will also start manufacturing railway bearings here. These bearings of a new generation provide its users with improved durability, increased operation safety and longer service intervals, thus significantly reducing operation expenses and improving reliability of the bearings.
New production line In order to achieve as efficient production as possible, the original machine structure needs to be replaced. That is why ZKL is introducing a new line production, which will reduce the share of manual labor related to the bearing manufacture by 66%. Three new employees will be necessary Page: 48
for operating the grinding line. The new ZKL production line includes machines for grinding sides, grinding surfaces, grinding orbits, grinding holes, grinding support faces and super-finishing orbits. Thanks to the new production line and utilization of modern, progressive grinding methods, we are able to reduce the grinding time by up to three times. The innovation and the expansion of the assortment of the roller bearings will also result in automation of measuring procedures of important parameters of individual bearing parts and in securing the so-called “genealogical tree” of each bearing produced on these lines.
Investment The expansion of the assortment of roller bearings by the ZKL Klášterec nad Ohří
represents an initial investment of 184 million Czech crowns. 159 million out of this sum will be used for purchasing new and modern production technologies, for example, technologies for lathe operations. Further 7 million Czech crowns represent investment expenses related to the preparation of the given building and the area for the roller bearing production line. The remaining amount, i.e. approximately 18 million Czech crowns, will be used for moving a part of the current production assortment technologies to newly modified areas. The above stated investment related to the given innovation and expansion of the assortment of roller bearings, amounting to more than hundred million Czech crowns, will be mostly paid from internal resources created within the frame of the ZKL GROUP. Other parts of the budget will be covered by the means of a loan obtained from Česká Spořitelna and by grants obtained from the Innovation and Properties projects. The total amount of the grants could reach up to 47 million Czech crowns.
New roller bearings line The ZKL Group exports its roller bearings throughout the entire world. After introducing the new production line, the plant in Klášterec nad Ohří will be able to produce a total of 47 types of roller bearings. And this number is not final. ZKL reacts to
the requirements and needs of the market and customers. That is why the company plans yet additional expansion of its assortment in the future. The ZKL plant in Klášterec nad Ohří will mainly specialize in the production of bearings of an “E” design, which are known for their increased capacity and a massive brass cage. Based on the needs of its customers, the “E” bearings will be also made with iron or plastic cages. Roller bearings made by ZKL are especially used for demanding transport devices. They must comply with the increased load capacity requirements and must be impact resistant. Thanks to their high-quality characteristics, the ZKL roller bearings can be also used for traction drives and drives generally. The core segment, to which ZKL will offer its assortment of axle bearings, is the railway industry. Railway industry represents a perspective area, into which ZKL would like to expand. Roller bearings, designed not only for the railway industry, must be of a top quality and efficiency. That is why their production requires the most modern machines. ZKL uses new, MKP-based calculation programs, 3D construction software and modern metallurgical processes, due to which the structure of the bearings is distinctly optimized.
ZKL news Apart from the actual innovation of this standard assortment of bearings, ZKL has been introducing various novelties to its customers. For example, the company has recently produced special, sixline roller bearings with 3 massive brass cages, installed along the inner ring. This NNU6088MB C3 NF bearing has an outer diameter of 650 mm and a total weight of 465 kg. Yet another type of roller bearings that is not available on a regular basis is NU0048M. This bearing is of a very slim design. With its outer dimension of 360 mm, it is only 37 mm wide and it weighs 14.5 kg. One of the bearings with a complete number of rollers is the NSF3016CV P5 NF type, manufactured in a higher accuracy class (P5). While the outer diameter of the bearing is 125 mm, it weighs only 1.5 kg. From among the bearings for railway applications, we can point out the new PLC 410-53/54.2 roller unit, which is formed by two single-line bearings with gaskets and permanent plastic lubricant filling. The bearing unit is designed for mounting axles of the RegioPanter electric units of Czech Railways.
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TOP 10 TIPS Bearing Reliability for
by Mr. Per Arnold Elgqvist
BearingTip No. 1: â&#x20AC;&#x153;Bearings are innocent until the contrary has been provenâ&#x20AC;?. Moderns bearings manufactured by recognized quality brands most only in exceptionally cases present defects. These manufacturers apply Zero Defect strategies and defects on their products are measured only in ppm (parts per million). Earlier bearings failed based due to fatigue caused by defects in the material, the design or the manufacturing process. Today the vast majority of bearings fail due to external causes: 1. Inappropriate lubrication. 2. Wrong bearing (Type and/or Variant).
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3. Contamination. 4. Misalignment. 5. Mounting damages. 6. Wrong bearing arrangement. 7. Overloading. 8. Bad quality of bearing seating on shaft and/or in housing. 9. False Brinelling. 10. Electric erosion. Thus as the reliability of bearings no longer depends on the manufacturer we now have the opportunity to act in a positive and proactive way: See each bearing failure as a challenge to identify the cause or causes and to determine and implement the required corrective actions to avoid the recurrence of the same failure.
Bearing News â&#x20AC;˘ Issue 3
BearingTip No. 2: How long should Bearings last? The answer to this question is of utmost importance as it will tell us if the failure of the bearing is natural or premature. If the bearing reached the recommended service life: Congratulations! Just replace it in the most professional way. But if the bearing did not reach the recommended service life the failure was premature and a root cause failure analysis in a must in order to identify the cause or causes and to determine and implement the required corrective actions to avoid the recurrence of the same failure! Be most careful and avoid the Workplace blindness: “This Bearing always fails every 10 months”!
2. The correct mounting. Use the correct mounting methods and tools to avoid damages to the bearings and other components of the machines. 3. The correct lubrication. In order to assure the optimal lubricant for each application the analysis must determine at least 5 properties for the lubricant indicating the corresponding ASTM, DIN or ISO test methods and required results.
BearingTip No. 4:
The leading bearing manufacturers indicate recommended guidelines for bearing lives for typical applications, like for example: “Machines used for short periods or intermittently where high operational reliability is required………8 000 to 12 000 hours”. “Machines for continuous 24 hours use…………40 000 to 50 000 hours”.
“Bearings are as good as their lubrication”. This statement is quite easy to confirm as each and every bearing fails as soon as the lubrication fails. No bearing is able to survive metal to metal contacts!
This last recommendation means that bearings in electrical motors shall last for 5 years with a reliability of 90% (L10h) and half of the bearings may last up to 5 times the calculated life (L50h). An example for this is that several manufacturers of high efficiency electrical motors extend guarantees for up to 7 years! This means that these motors should only be lubricated and condition monitored and not opened for 7 years.
BearingTip No. 3:
See the example below: A 241/900 spherical bearing with a weight of 3,350 kgs in a cement mill failed after only 105 hours in operation due to incorrect lubrication! It should have last for years! In this case commercial EP2 grease was used instead of the recommended special high viscosity calcium sulphonate grease.
The 3 steps to the Reliability of Rolling element bearings.
So be it that several statistics indicate that 55% or even more of bearing premature failures are caused by inappropriate Lubrication. What an opportunity!
Follow the 3 basic steps to achieve the required reliability of your bearings:
A totally correct lubrication must include the following:
1. The correct bearing for each application.
1. The correct lubricant.
Each and every application must be analyzed in detail in order to determine the optimal bearings and their precise characteristics. The correct bearing must not only take in account the bearing type and size to comply with the loads (Basic designation) but also the variant (complementary suffixes) required for the working conditions.
2. The correct Lubrication method/system. 3. Application in the correct place. 4. The correct quantity. 5. The correct re-lubrication. 6. The correct people performing the lubrication,
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with sufficient knowledge and training (= Tribologists).
BearingTip No. 5: “Rolling element bearings must reach their mounting still being virgins”! The best way to avoid new Bearings to be contaminated is very easy: Keep them in their original package until their mounting, unopened as virgins as in the very old days! If new bearings still are in their original packages and the designations are original and complete and are completely in accordance with the required Bearings there is absolutely no need to open the packages until the moment when everything is ready for their mounting. We have always known that contamination “very much” reduces bearing life. But we did not know what “very much” was until year 2000 when the ISO 281 formula included the contamination factor ηc. The effect of contamination exceeded our worst ideas! I use to show 2 examples in my courses: The bearing life calculated utilizing this formula for a deep groove bearing heavily contaminated as it was unpacked exposed to all the usual particle contamination of a repair shop and used for the measurements in the workshop to repair shaft
enormous benefit? None at all!
BearingTip No. 6: The costs of rolling element bearings are insignificant compared with the costs caused by their failures. The total costs caused by bearing failures are in most cases enormous. Especially when you as you should take in account the value of the production that was not produced due to downtime caused by the failure. In most reports I have seen the cost only include the costs for the repair when the value of the lost production may be 10 or up to 100 or more times higher. Let’s look at a simple example: The failures of deep groove ball bearings 6210 in felt rolls in a paper machine as shown in the figure below. These bearings should only function as guide to avoid excessive misalignment of the spherical roller bearings during the handling of the roller and all the load should be taken up only by the spherical roller bearing. In this case it was decided to increase the speed of the machine and thus the tension of the felt was also increased accordingly in such a way that the increased misalignment of the roller caused heavy unexpected loads on the deep groove ball bearing causing premature failures. The cost of each bearing was 50 USD. According to the plant manager each failure caused 2 hour downtime with a total cost of 15,000 USD per hour due to the lost production. Thus a relation of 50 to 30,000!
and housing which means exposed to possible handling damages besides the contamination. This bearing is given the contamination factor of 0.1! As comparison an unopened bearing with the cleanliness direct from factory assigned the factor of 0.8. The calculated life was increased 12 times for the second bearing! And what was the cost for this
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This was in an old machine so just imagine the cost in a modern machine, as for example the largest machined manufactured so far that produces 28,000 tons per day. So I’m sure there are even much worse examples! In this case I recommended
Bearing News • Issue 3
replacing the bearing by a simple bushing with the diameter big enough to avoid an excessive misalignment of the spherical roller bearing but a clearance enough not to touch the housing during operation. The cost: 20 USD!
Utilize the â&#x20AC;&#x153;Tribological Formulaâ&#x20AC;? to increase the lives of rolling element bearings!
Conclusion: Always look for the total costs for the failures.
I have called the ISO 281 edition 2000 (and later) formula shown below for calculating bearing life the Tribological Formula.
BearingTip No. 7: Wrong Bearings = the 2nd mayor cause for Bearing Premature Failures!
As Tribologists we talk about 3 main types of wear: 1. Fatigue or spalling. 2. Adhesive wear.
My experience on the field has shown wrong bearing to be the second mayor cause for premature failures! Why so? It is clear to me that the lack of knowledge in bearing designation is the reason for most of these mistakes. Just look at the example below: The catastrophic failure of the thrust bearings in an API centrifugal pump in a refinery. The designations of the 2 bearings made evident that these had not been adjusted for mounting in pair which had led to an incorrect thrust preload in between the 2 bearings originating a heavy overload. These bearing should have had the suffix UA indicating the required adjustment made by the manufacturer. 1. Wrong internal clearance. I use to ask what C3 means as I start my training courses and my experience is that most of the participants do not know and a correct internal clearance is most critical for the correct function of bearings.
3. Abrasive wear. This formula for calculating bearing life takes in account the aISO factor. This factor takes in covers the causes for the 3 types of wear indicated above: 1. The relation in between the applied load and the fatigue load limit for the corresponding bearing. 2. The lubrication conditions, mainly the Kappa relation i.e. the relation in between the actual viscosity of the lubricant and the minimum required viscosity to avoid metal to metal contact. 3. The contamination as regards solid particles
2. Wrong type of integral seals. It is a most common misunderstanding that shielded bearings (-2Z or ZZ) are sealed which they are not: There is a small opening in between the metal shields and the inner ring to avoid contact, which allows the lubricant to leak out and contamination to enter the bearings. Â Bearings provided with contact seals are almost hermetic and are the indicated to perform correctly in contaminated environments. Just look at the different contamination factors the ISO 281 assign: 0.5 for the capped bearing and 0.85 for the sealed bearing.
BearingTip No. 8:
expressed as ISO 4406 code, i.e. the quantities of particles larger than 4, 6 and 14 microns per ml. of the lubricant. Page: 53
Before the publication of this formula we talked about the “severe damages” ofsolid particles, but unable to quantify “severe damages”. Now we have an official tool to quantify this type of damage and the fact is that its enormous effects surprised most of us. Just imagine, this factor axyz may have a value from almost 0 (zero) to 50 that is the upper limit. Up to 50 times the previous calculations!
the fits, the correct adjustments (axial clearances or preloads) and lubrication data (lubricants and quantities).
As just one example I can mention that the contamination factor for open bearings being re-lubricated is 0.25 and this factor for factory lubricated and sealed bearings is 0.85! Conclusion: Use as many sealed bearings as possible!
- Unnecessary bearing failures.
The latest 2007 edition of the ISO 281 indicates: “Below a certain load, a modern high quality bearing can attain an infinite life, if the lubrication conditions, the cleanliness and other operating conditions are favourable”. What an opportunity!
BearingTip No. 9: Do not systematize the errors in your CMMS Program! The CMMS (Computerized Maintenance Management System) Programs are excellent as long as you guarantee the quality of the information you feed into them. These systems can be outstanding as information sources when you need to repair equipment. If you use it as it is intended you can have all the necessary information in seconds at your finger at the system terminal: All the spare parts needed for the repair (bearings, seals, components, etc.), the required mounting tools and tolerances for SAP NO.
But the above is only the truth if you take the correct care when you feed the information into the systems. Unfortunately I have seen to many bad examples where wrong bearing information is being fed into the systems. This will cause several problems: - Excessive stocks in the warehouses. Just to show you an example: A failure of an API centrifugal pump showed to be caused by a wrong bearing so I asked to see the information in the SAP System at the client. The correct bearing should have been a 7310 BECBM in the SKF brand or its correct equivalents in other brands. In the following table you can see what I found. The bearing that should have been only one (SKF Ref. 7310 BECBM) was indicated as 12 different SAP numbers and not one single of them was correct! Some missing the suffix indicating the required adjustment for mounting in pair and not one single with the correct machined brass cage as indicated by the API 610/ISO13709. In my experience the lack of knowledge in bearing designation is the reason for the 2nd largest cause for bearing failures: Wrong bearings.
BearingTip No. 10: The optimum seal, the triple barrier! Deep Groove ball bearings exposed in heavy contaminated areas can be protected in a very efficient way. By heavy contaminated I mean both particles and water. The most usual way to avoid contamination
Bearing
Actual Bearing Designation
100010463
1 Row Angular Contact Ball Bearing
SKF 7310
7310 BECBM
100010505
1 Row Angular Contact Ball Bearing
SKF 7310BG / ROLLWAY 7310BCB
7310 BECBM
100010562
1 Row Angular Contact Ball Bearing
SKF 7310 B
7310 BECBM
100010486
1 Row Angular Contact Ball Bearing
FAG 7310BUO
7310 BECBM
100024093
1 Row Angular Contact Ball Bearing
SKF 7310BG / ROLLWAY 7310BCB / 7310 BECB
7310 BECBM
100026265
1 Row Angular Contact Ball Bearing
SKF 7310
7310 BECBM
100030353
1 Row Angular Contact Ball Bearing
SKF 7310BG / ROLLWAY 7310BCB / 7310 BECB
7310 BECBM
100038446
1 Row Angular Contact Ball Bearing
FAG 7310BJP
7310 BECBM
100055771
1 Row Angular Contact Ball Bearing
X TODA MARCA 7310BEC BY
7310 BECBM
100055789
1 Row Angular Contact Ball Bearing
SKF 7310
7310 BECBM
100080937
1 Row Angular Contact Ball Bearing
SKF 7310BEAG
7310 BECBM
100125459
1 Row Angular Contact Ball Bearing
BYRON JACKSON PARTE NO.7310
7310 BECBM
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Ref. SKF
Bearing News • Issue 3
to enter the bearings is by using intensive relubrication with grease. In several occasions I have recommended so called triple barrier protection: 1- Replacing the open bearing by capped or sealed bearing. 2- Filling the bearing housing100% with grease. 3- Outer seal being a V-Ring or efficient labyrinth. See the figure below: I can mention 2 examples: 1. Blowers in the open at copper mines up in the mountains in South America. Service life increased from 6 months to over 2 years. 2. Electrical motors in the basement of paper mills. These even survived also electrically being totally flooded. And in both cases these equipment had become maintenance free!
Per Arnold Elgquist Mr. Per Arnold Elgqvist has 34 years of experience in SKF as Quality, Product Engineering and Reliability Services Manager. He works since 10 years as private consultant for the industry in Mexico, Venezuela, Brazil, Colombia, Peru and Argentina. Learn more about â&#x20AC;&#x153;Bearing Failures and Their Causesâ&#x20AC;? at www.reliabilityinstitute.com
KEY CONSIDERATIONS
FOR DESIGNERS LOOKING AT BEARING SYSTEMS WITH
LINEAR AXES
The majority of electro-mechanical axis utilise extruded aluminium profile in a range of sizes with a single guide rail and bearing arrangement driven by an electric motor through a belt or ball screw arrangement. There are physical limitations to the forces such a system can accurately and reliably guide. This paper explores some alternative design arrangements to cope with higher load applications and identifies design considerations observed during the development of a Festo high load, twin rail system.
Supporting profile design To ensure bearing life was maintained in the twin bearing axis, the tolerances were carefully defined for the contact surfaces of the profile with the linear bearing guide rail. It was determined that to deliver a high performance guide system the supporting aluminium profile would in itself need tobe extremely strong, rigid and accurately produced. To ensure the lifetime of the system the axis need to be available in lengths up to 9m long, installed with a parallelism of +/- 0.05mm and a flatness deviation of less than 0.2mm. Working extensively with several extrusion manufacturers, it was determined that again using the internal arch principle, it is possible to manufacture a profile to the required stiffness tolerances for the axis, but they were not able to deliver the flat bearingmount surface. Instead a special machine tool had to be developed to mill the surface of the extrusion where it meets the guide rail on the standard 5.5m, or special order extended 9m, profile lengths. Research had shown these profile sizes would cover the majority of customer applications. Although extra machining adds to Page: 56
Fig. 5 Cross section of single guide axis belt drive electromechanical axis (arch profile highlighted)
the overall production costs, this was deemed to outweigh by the benefit of a tenfold improvement in accuracy. The development of such a machine was challenging, as the profiles can weigh 125kg so again this was a custom development just to suit this product need.
Bearing News â&#x20AC;˘ Issue 3
Cupola arch – applied in architecture and now, electrical and mechanical axis Often, manufacturers of mechanical axes will have a very high quality rail but bolt it to a profile that is not particularly stiff; the result being that the whole structure flexes – similar to having a high performance car engine bolted onto a chassis that flexes and bends while cornering, thus reducing the overall performance of the car. For the original standard axis, and during the development of the twin axis system, a very stiff profile was developed using a Cupola arch system – a design pioneered by Da Vinci and utilised extensively by Gaudi. This incredibly stiff profile allowed a rail on the profile so that nothing gives – the axes itself is used as the structural member of the system. Instead of bolting a mechanical axis onto a structural member, with the Cupola arch system, the mechanical axis becomes the structural member – saving considerable weight, as well as assembly time and the associated costs.
Bearing System During the development phase, the key focus was on the rigidity of the bearing system. In the early trials, the well proven caged ballsystem from the existing single axis system [EGC] was used but as identified, these failed within 500km - not just once but also on retest. The linear guide initially selected wasidentical to the proven design used on the single rail systems, a high performance and very stiff solution. In this instance though, the balls and rail in the bearing were not designed to deflect and therefore did not compensate for the alignment tolerances in the dual rail design; hence the failure. There are many ball bearing arrangements and different bearing manufacturers can select from many variables to optimise their solutions these include, the number and size of balls in contact, their arrangement, contact angles and how the balls are retained.
Fig. 8 Drawing showing the evolution and application of the very strong and stiff Cupola arch
Each bearing manufacturer constructs different arrangements; a bearing that has an O-arrangement and ‘caged’ from one manufacturer, for instance, may not necessarily have the same characteristics and performance of a similar type from another manufacturer. This can be due to other design differences, they may have higher or wider dimensions or the size of balls differ. Effectively, the different combinations of bearing systems available on the market vary widely and choosing the optimum system can be very complex, a close development relationship with the bearing manufacturer is important. Bearing Technology Whitepaper For the EGC-HD an alternative linear guide bearing system was therefore considered which used bearings with larger diameter balls. Smaller balls have more points of contact to accommodate the load and offer good stiffness. Bigger balls, means fewer balls in the bearing cassette and therefore fewer contact points. Page: 57
However, with larger ball sizes, the ball itself can compress slightly, compensating for tiny but important mis-alignment tolerances; imagine a football pressurised to 10psi, this can be squashed or deflected more easily than a tennis ball at the same pressure. Therefore it was determined bigger ball sizes would minutely deflect and be technically better for this system with incredible inherent stiffness and yet tolerances need to be catered for. In this twin rail system, there are heavy loads therefore bearing ball size has compromises and the optimum size has to be very carefully selected. The rail profile is very stiff so there is very little deflection, all the movement has to be accommodated by the balls themselves. So, the ball size chosen for the twin rail system was slightly larger than the ones used in the single rail axis. In all, different bearing systems from the different suppliers were evaluated. Designers would naturally select a proven solution that has performed reliably for many years but this example shows that sometimes, the wheel really does need to be re-invented to get the correct solution. What works well in one configuration could not be simply ‘cutand- pasted’ into another.
Once design was completed and the new bearing system integrated, 6 months of durability testing recommenced, this time with no failures. After 5,000km no signs of wear were detected so the tests were extended. Even after 10,000km all was well. It is estimated that the average service life of an axis of this type within a machine is approximately 3,600km, therefore the new design comfortably offered the operational safety margin required.
Lessons to be applied Whilst a very stiff and accurate profile (frame) is necessary for highly precise applications, the lack of compliance in such a system has to be carefully considered. Simple linear bearing systems can be accurately modelled and their performance predicted but bearing systems can quickly become complicated and existing computer models cannot factor in all the variables and accurately predict operating life. There is no simple selection of the ‘best’ bearing: caged or non-caged, X or O configuration, ball size etc., all have to be determined and paired to the application. Engineers should factor the choice of guide system used into their overall design, especially in systems that carry large masses and are typically connected to a stiff structure.
Conclusion For a one-off, special purpose machine designer it wouldn’t be practicable to undertake such an evaluation of the options [time or cost] and the temptation would be to massively over-engineer their solution or risk premature machine failure
Final test phase Festo Ltd Applied Automation Centre Caswell Road Brackmills Trading Estate Northampton NN4 7PY Phone 0800 626422 Fax 01604 667001 E-mail: info_gb@festo.com Internet: www.festo.com/gb
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Bearing News • Issue 3
CASE STUDY:
MONITORING OF A PAPER ROLLING CY
WI-CARE WIRELESS VIBRATION AND TEMPERATURE CONDITION MONITORING SYSTEM It is now possible to reduce most of these costs. The installation of a wireless vibration monitoring system coupled to remote condition monitoring diagnosis provides some of the answers. The following case study represents a typical remote analysis application of a paper rolling cylinder. The monitoring was performed in a very effective way for the customer and analyst: For the Customer: Quick installation of continuous data collection for their critical asset with no retrofitting. Almost impossible to install wired system due to equipment movement characteristics. For the analyst: Continuous data (Historic and Remedial Action Recommendation) from the monitoring Center without any travel or
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measurement time spent. No waste of time due to tear paper, roll changing or cleaning operation.Â
Equipment, plant overview, Context The Manufacturing site is a Paper Plant, established in Eastern Europe. where the equipment ,installed 4 years ago ,is operating at full capacity, The Equipment in question is a Paper roll up system at one side of a coating
Bearing News â&#x20AC;˘ Issue 3
YLINDER
line. The equipment is fully automated to allow roll replacement without stopping the line. This represents an enormous advantage in terms of production capacity but also a â&#x20AC;&#x153;nightmareâ&#x20AC;? for traditional condition monitoring techniques due to large movements of the rollers (see video). Several bearing failures had already occurred on the main roll shaft leading to maintenance and production shutdown. The Customer requested I-Care support via Wi-care wireless system to monitor continuously bearing condition, checking in particular for evidence of looseness in the collected spectra.
Analyst diagnosis and spectrum justification: Looseness â&#x20AC;&#x201C; Bearing frequencies
Instruments deployed in the condition monitoring market for data collection are generally either portable data collectors in a manual/ walk-around measurements mode or permanently installed online systems that continuously collect and store data of high criticality assets. However, there are still a number of drawbacks to wider installation such as: The high cost of cabling and installation; Purchase of and personnel training on analysis software; insufficient justification for a permanent system; machines where fixed cabling is not possible.
The Wi-care system was installed on the main shaft in minutes using magnetic locators to cover the two bearing locations in the vertical & horizontal planes. Standard spectrum collected via Wicare in the vertical axis. The dominant frequency appears at 798 Hz and its harmonics. On a closer zoom (Graph on Right hand side) we can see the rotation frequency 18 Hz and its harmonics. The amplitude are still low 0,10-0,20 G Peak.
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Data analysis indicates a low level of vibration at this stage and almost no defect. Nevertheless, We can clearly see and monitor the first track of possible looseness (1XRPM multiple). You may recall that bearing looseness was the origin of previous breakdowns. The Wi-care
Wi-care product and remote diagnosis overview How does it work ? The Wi-careâ&#x201E;˘ system is the latest wireless condition monitoring system from I-Care. The system has been designed to detect, measure and analyse the root causes of excessive levels of vibration and temperature. The Wi-care system is a cost-effective tool used to report any vibration or temperature deviation in a short time. The I-CARE team of engineers using the data from Wicare are able to give you a condition monitoring remote diagnosis at any time 24 hours a day/7 days a week. The condition based maintenance partnership has been created to give you the chance to correct a potential problem before it occurs. The solution developed in the Wi-care system is based on a receiver connected on the internet and able to manage up to 144 transmitters, each transmitter sending vibration and temperature data. In order to reach long distance data transfer and remote locations, the WI-care involves a range extender in its network. Using a web-based portal to manage the system avoids any extra cost and any Page: 62
system clearly demonstrates its ability to monitor 1XRM_PM multiples from a very early stage ensuring detection of eventual future looseness. The decision was taken to invest in permanent Wi-care monitoring of the rollers.
difficulties linked to the software. We all know how frustrating it is when you are waiting for your data analysis and you canâ&#x20AC;&#x2122;t make any quick condition based maintenance decision due to software issues. www.wirelessvibration.eu
Added value? Online monitoring based on permanent wired sensors can be expensive in many applications. Wireless monitoring with wireless vibration sensors improves the reliability of difficult-to-monitor assets with quick and cost effective installation. Wireless vibration monitoring gives added value in a more flexible system, cutting expense and labour costs on installation and maintenance of the old wired vibration and temperature sensors. You simply attach the sensors using extra-strong magnets where you need them and in minutes they create a large network of real time data transmission to the gateway data manger in tandem with the range extender. The solution created by Wi-care is very flexible and cost effective because it allows the reuse of existing piezoelectric vibration sensors which can be turned into wireless vibration sensors with the single action of plugging the sensor into the Wi-care transmitter. Bearing News â&#x20AC;˘ Issue 3
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THE BEARING OF THE
FUTURE a study by Kurt Bauwens and Marc Grunewald
A new family of roller bearings in which the radial play is eliminated, offers a lot of advantages and possibilities in nearly every application field. Active compensation of variations of temperature, elimination of uncontrolled behavior of the rollers in the radial clearance zone, support of all composing parts of the bearing offering more stability, dimensioning possibilities of the revolution speed of the components of the bearing because of the off set contacts of the rollers on the inner and outer ring, traction possibilities in applications with inertia forces, new strong lay out for reductions, planet gear systems etcâ&#x20AC;Ś The rollers of this new technologic bearing are running totally synchronized on the inner and the outer rings. Check out the comparison between actual bearings and the bearing of the future!
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Bearing News â&#x20AC;¢ Issue 3
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Bearing News â&#x20AC;¢ Issue 3
A COMPARISON STUDY
FOR BEARING MANUFACTURING Page
CHINA INDIA VS
124
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Bearing News â&#x20AC;¢ Issue 3
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For 40 years JESA has been offering tailored and customized solutions for tough challenges! Today the company is known as “The Specialist” in tailored bespoke solutions, containing ball bearings, machine parts and stampings, often in combination with engineering polymers. Page: 74
Bearing News • Issue 3
The Perfect Bond Between Bearings And Plastic
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The Perfect Bond Between Bearings And Plastic Mr. Marcel Dubey, Managing Director at JESA
JESA is today still working on the mission to be and to stay the preferred partner for the development and production of high-precision bearings and mechatronic drive units composed of metal and plastic. The company has been through a period of new developments and structural changes in order to adapt to the new dynamic industrial environment in the world. We tried to learn more about the “tailored solutions” of JESA during an interview with Mr. Marcel Dubey, Managing Director at JESA, located in Villars-sur-Glâne, Switzerland.
What do you mean by “tailored bearing solutions”? During the development phase of a vehicle, a coffee machine or a conveyance chain, an engineer is frequently confronted with a multitude of constraints. The role of JESA in the development phase is to eliminate the restrictions and obstacles facing the engineer. We do this by going beyond the limits of catalogue products by developing ball bearings and tailored units that are completely adapted to the applications of our customers. Personalization of our tailored solutions is something we hold dear. Innovation, flexibility, quality and benefit for our customers are therefore Page: 76
our watchwords. Our modern machine park has also been designed and developed with a view to ensuring impeccable performance and quality. Its flexibility also enables us to offer logistical solutions that are ideally adapted to the needs of modern industry.
When did JESA start the production of bearings and how was the evolution in the company? April 1969 : Foundation of J. Egger SA 1971 : Start of production of special ball bearings 1976 : Construction of factory in Villars-sur-Glâne 1979 : Construction of workshops : mechanical, plastic injection, stock, arrivals, dispatch, cafeteria 1992 : Expansion of factory in Villars-sur-Glâne, company obtains ISO9001 certification 1998 : Expansion of the headquarters 2001 : Acquisition by Polygena 2003 : Foundation of JESA China in Wuxi
Can you give us an overview of JESA products? JESA’s core business is the manufacture and design of ball bearings. JESA responds to the most
Bearing News • Issue 3
challenging and specialized demands from the market by offering tailormade products which have a basic requirement for ball bearings. The most varied ancillary parts made of metal, ceramics, magnesium or plastic are perfectly integrated, to offer the following range of solutions : • Ball bearings units • Overmolded bearings
Advantages • Self-alignement at assembly • High axial load capacity • Seals optimisation PROFILED TRACK ROLLERS
• Bespoke bearings solutions • Miniature ball bearings (2 - 4 mm inner dia.) • Standard ball bearings according to ISO 15
What is your company sales by turnover and markets? Turnover by market segment: • 51% industry • 20% automotive • 14% building • 13% consumer goods • 2% medical
Can you describe a few application examples where JESA custom bearings are used?
Application Guide wire Advantages • High load capacity • Limited radial clearance • Less cost of manufacturing
ASYMETRIC ANGULAR BALL BEARING BACK-UP BEARING
Application Application Power tool
Vacuum pump Advantages
Page: 77
• High static and dynamic load capacity • High precision • High acceleration capability
What is your difference with the competitors on the market? We adapt our products to the customer needs, after precisely defining various criteria such as shape, load, materiel, lubrication or even water tightness. Our solutions based on bearings and plastic injection are developed in partnership with our customers. With rigorous and professional project management, JESA is able to successfully implement tailored designs. At JESA, we offer personalized service and technical support in accordance with the ISO or the automotive quality system standard. We can also provide bearings in combination with plastic. For each application, the ideal synthetic material as well as an optimized design of the ball bearing overmolded by JESA facilitates a long life, high allowable loads, low wear and quiet operation. The JESA engineering team analyses each application from A to Z in order to develop and manufacture a custom product that perfectly matches the specifications. With JESA’s ease in the field of implementing plastics, special technical
Page: 78
polymers, the precise profiles and complex shapes are the JESA capabilities serving the innovative industry.
What is your latest product development? Responding to strong market demand, JESA launched recently a standard version of its roller, until now custom produced. Each parameter was analysed, redesigned and optimised, both from a geometric standpoint and at design level in order to be able to offer a standard “LRG” product line, exclusively Swiss Made and with maximum efficiency. JESA also is standardizing a series of specific chain rollers for plastic film stretching machines. More than ten years have passed since the Fribourg company started the production of the “LR 202″ roller type for major plastic film producers in Germany. A specific range has been created to meet demand appropriately. More information on JESA website: http://www. jesa.com Custom bearing: http://www.jesa.com/en/ bearings/custom-bearings/ LRG: http://www.jesa.com/en/bearings/ standard-bearings/profile-rollers-lrg-serie/ LR202: http://www.jesa.com/en/bearings/ standard-bearings/lr-202-roller/
Bearing News • Issue 3
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Page: 79
Bearing News â&#x20AC;¢ Issue 3
How NN is Driving the Future of Bearing Components Most people expect product quality and product performance to improve over time, and in many cases, they do. The automotive industry is but one example. Vehicle manufacturers make a very complex device that is a combination of mechanical and electrical systems. It is expected to perform flawlessly for at least the first several years of service. As these companies have come to understand and implement a wide range of quality tools, our cars have become more and more reliable. We, as consumers, do not expect to take a vehicle back to the dealer for anything other than routine maintenance and even those service intervals are being extended out. As reliability continues to improve, we also expect that the performance and content of the vehicle will continue to increase. We want higher fuel efficiency, but we do not want to compromise on the acceleration or load carrying capability. We also want our vehicles to be quiet and smooth, while providing all those gadgets we have become accustomed to when we travel. (Who knew we would need 12-way adjustable seats with heating and cooling?) Beyond all that, our vehicle should be attractive and comfortable. A successful automotive company has to master all of these different systems and be able to integrate them into a car that we want to drive. The balls and rollers that go into the various Page: 80
bearings used in the modern automobile would seem to be very simple and unchanging. The bearings themselves are tucked away in the vehicle’s components and are invisible to most people. They are present in the wheels, transmissions, axles, engines, alternators, power steering systems, power windows, and even the electric motors that make those 12-way adjustable seats move in all those directions. So what needs to change in the balls and rollers, or rolling elements, inside of the bearing to make our personal transportation more reliable, more efficient and even more comfortable? All those systems that were mentioned above (elements that rotate under load) are only as reliable as their weakest link. In many cases, the highest mechanical stress in the system is on the bearing, and within the bearing, the rolling elements carry the brunt of this for what should be millions and millions of loading cycles. If one of those little balls inside one of your wheel bearings fails, you could end up with some unpleasant noises in the best case, or worse yet, potentially some degradation in the steering or braking of the car. So what could possibly change on something as simple as a ball or roller? At NN, we have spent our history continually working to make these simple components better and less expensive. Over time, the purity of the Bearing News • Issue 3
“Most people expect product quality and product performance to improve over time, and in many cases, they do. The automotive industry is but one example. Vehicle manufacturers make a very complex device that is a combination of mechanical and electrical systems. It is expected to perform flawlessly for at least the first several years of service. As these companies have come to understand and implement a wide range of quality tools, our cars have become more and more reliable. We, as consumers, do not expect to take a vehicle back to the dealer for anything other than routine maintenance and even those service intervals are being extended out.”
Jeffrey Manzagol Senior Vice President, Metal Bearing Components Group
raw material we utilize and improvements in the heat treatment procedures have made our products last longer and remain strong in harsh environments. The surface finishes on the elements gets better and better, and the size variation from one to the next continues to decline. We are talking about a fraction of a micron in variation from one element to the next. Manufacturing defects that actually escape our plants are truly a rare occurrence. Simultaneously, our manufacturing process generates less pollution and consumes less energy, while generating less scrap to be recycled. In recent years, we have doubled down investing more than ever on both product and process development. We have established two Research & Development centers, one for balls and one for rollers, at two of our flagship facilities. In our R&D centers, we have dozens of engineers working on analyzing the performance and quality of our current products (and those of our competitors), developing new processes to make them better, faster, less expensive and with less impact on our environment, and always looking out for the next generation. Some examples of things we are working on today for future implementation include: Tapered and cylindrical rollers that generate even less torque, thereby reducing energy consumption for cars, trucks, and a wide range of machines.
Moving away from Oil-Based to Water-Based lapping compounds. This improves our environmental impact and reduces costs. Inspection methods that eliminate the microscratches on the surface of the rolling element. Robot-assisted ball manufacture that reduces costs and handling damages and reduces the manufacturing floor space required. Zero Defect Technology on roller manufacturing that eliminates the chance of outliers for material and forming defects. NN believes there is always room for improvement, even for products that look relatively simple and have been around for more than 100 years. NN’s Metal Bearing Components Group is the global leader in the bearing components field and fully understands the need to continually invest in future technologies. We push the envelope on what we do and how we do it, all to benefit our customer and their customers. NN, Inc., a diversified industrial company manufactures and supplies high precision metal bearing components, industrial plastic and rubber products and precision metal components to a variety of markets on a global basis. Headquartered in Johnson City, Tennessee, NN has 25 manufacturing plants in the United States, Western Europe, Eastern Europe, South America and China. Page: 81
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What Happened in the
Bearing Industry Second Half of
2014
What Happened in the
Bearing Industry Second Half of
July
July
2014
01
NSK released a guide to ‘Bearings for Pumps and Compressors’
02
NN, INC. Acquires Tapered Roller Bearing Company
Leading bearing manufacturer NSK has released a guide to ‘Bearings for Pumps and Compressors’, which contains information on the very latest bearing designs and technologies and matches them to various pump types and configurations in order to keep the industry moving forwards. NSK’s guide to ‘Bearings for Pumps and Compressors’ is available in both paper and electronic format; the pdf can be downloaded directly from the NSK website here: http://nskeurope.com/cps/rde/xchg/eu_en/hs.xsl/downloadsectors.html
NN, INC. announced that it has acquired 79.2% of the outstanding shares of RFK Valjcici d. d. Konjic. RFK is a manufacturer of tapered roller bearings with operations in Konjic, Bosnia & Herzegovina. Its products, while complementary to NN’s existing roller bearing products, will broaden the Company’s product offering and allow penetration into adjacent markets. NN expects to acquire the remaining shares of RFK in the near future. Financial terms of the deal were not disclosed.
RFK, a listed company on the Sarajevo Stock Exchange was founded in 1984 and is expected to have sales of approximately $12.0 million in 2014. RFK currently exports all of its products, predominately to customers serving the European truck, industrial vehicle and railway markets. NN will continue operations at the existing facilities in Bosnia and will roll up the operations under its NN Metal Bearing Components Group. Page: 86
Richard Holder, President and Chief Executive Officer of NN, Inc. commented, “We are pleased with the addition of RFK to the NN family. This acquisition along with the announced acquisition of V-S Industries in February of this year, are key first steps in the execution of our strategic growth plan. The acquisition of RFK increases our global manufacturing footprint in Eastern Europe and will strengthen our current product offering to our existing customer base while allowing us to further penetrate the truck, industrial vehicle and railway markets. We remain actively engaged in discussions with other acquisition targets and expect to announce additional transactions in the near future.” Mr. Nermin Niksic, Prime Minister of the Federation of Bosnia and Herzegovina stated, “I am strongly convinced that this acquisition would ensure a safe future for the employees and launch positive signals attracting further investments into Bosnia and Herzegovina.” NN, Inc. manufacturers and supplies high precision metal bearing components, industrial plastic and rubber products and precision metal components to a variety of markets on a global basis. Headquartered in Johnson City, Tennessee, NN has 12 manufacturing plants in the United States, Western Europe, Eastern Europe and China. NN, Inc. had sales of US $373 million in
2013. Bearing News • Issue 3
July
03
Local Community Residents Visit NMB-Minebea Thai’s Wastewater Treatment Facilities NMB-Minebea Thai’s Bang Pa-in plant welcomed 19 people from nearby Watthammanawapatthana community to understand the plant’s wastewater treatment system and toured the wastewater and rain water treatment facilities. After the tour, the participants had better understanding of the plant’s wastewater treatment, water conservation initiatives and satisfied to see plant wastewater is recycled inside the plant to the greatest extent possible and prevent external emission through our “Plant Wastewater Zero System.”
July
04
New Roller Bearing Company will create 50 jobs in South Carolina Meter Bearings, specialized in the production of roller bearings plans to open a plant in South Carolina’s Colleton County. The $4.5 million investment is expected to create 50 new jobs over the next five years. The plant in Walterboro will be the first American manufacturing operation for Meter Bearings Group of Torino, Italy. The state commerce department and Gov. Nikki Haley’s office announced the new plant . Production is expected to begin in September 2015. The company designs and produces ball and cylindrical roller bearings and has other plants in Italy and China and customer support operations in the United States and Germany.
July
07
ZKL Large Size Bearings for Mining Industry ZKL is dispatching nowadays 3 types of large size bearings for key customers from the mine industry segment. These bearings have the denomination of PLC 512-39, PLC 612-45.T3 and PLC 412-64. T3. The PLC 512-39 bearing was delivered to important Czech mining company. This spherical, cross-split roller bearing has large size and is used for the shaft imposition in the mining lift that transports the spoil above ground.In the comparison with the standard bearings the cross-split bearing can be mounted in markedly shorter time. The time saving can reach even couple days. The operation of this bearing is constantly monitored by the ZKL vibration diagnostics. The diagnostic unit primarily controls the vibrations progress trend, the operation temperature is observed secondary.The aim of this monitoring is to reveal the damage of a bearing already in the inception phase. This enables more effective planning of service intervals and contextual costs savings. Special bearings denoted PLC 612-45. T3 and PLC 412-64.T3, destined for the imposition of main cylinders in vertical mills, form part of one of the project executed for a Chinese customer. PLC 612-
45.T3 is double row tapered roller bearing with pin-type cage and X arrangement of the rolling elements. PLC 412-64.T3 is a single row cylindrical roller bearing with massive, brass cage.
The vertical mills are employed for the cement production on the basis of primary rock milling.The bearings work in very demanding condition such as high level load, eminent slack action and temperature up to 200°C. Both products are produced in P5 precision and they have case-hardened rolling elements. Page: 87
What Happened in the
Bearing Industry Second Half of
July
09
2014
Timken Investing $22 Million in New Selling Support Infrastructure The Timken Company is investing $22 million in new customer and sales management tools, designed to improve the customer experience through increased sales force effectiveness. “Timken is well-recognized in the marketplace for its know-how, engineering skills and service support,” said Richard G. Kyle, president and chief executive officer of Timken. “We invest heavily in developing the best and most technically qualified sales force in our industry and our people are highly respected by our customers.
July
10
Warehouse ABF Bearings further modernised are deliberately opting to have a large range of bearings in stock. We currently offer more than 100.000 different bearings in our webshop. These are all delivered from stock. We can also immediately deliver the “specials” worldwide. This choice means that we must be creative with the available warehouse space.” According to Quirijn Fabrie (ABF Bearings).
ABF Bearings has further modernized one of its warehouses due to the need for extra storage space. The previously available storage space of 6,000 m2 is insufficient for the ongoing growth of the stock. “We
July
12
A new concrete floor has been poured in the warehouse. New warehouse shelving was then installed. The warehouse now has narrower gangways in order to optimize use of the space available. This has prompted the acquisition of a special reach truck that is suitable for these narrow gangways. Here are several photographs of the building and set-up of the warehouse.
JTEKT Corporation doubles size of manufacturing facility in Richland County, South Carolina JTEKT Corporation, a leading producer of bearings, automotive steering systems and all-wheel drive couplings, has expanded its Koyo-brand bearing manufacturing facility in Richland County, South Carolina. The 250,000 square-foot expansion will provide JTEKT with needed capacity to manufacture automotive wheel bearing hubs for its growing U.S. customer base and is expected to create 175 new jobs in the next three years. In addition to a $130 million investment by JTEKT, the project was made possible with support from Gov. Nikki Haley, the state of South Carolina, Richland County and the city of Blythewood.
Page: 88
Bearing News • Issue 3
July
14
NKE Austria receives “Hidden For achievements in the Austrian exportChampion business. 3.0” award for achievements in the Austrian export business NKE Austria GmbH has been awarded “Hidden Champion 3.0”. The ceremony took place at the Austrian Export Day of the Austrian Chamber of Commerce in Vienna. The famous export prize is awarded to companies which render outstanding achievements in the Austrian export business. The certificate was presented to Mr. Rudolf Pirklbauer, Head of Key Account Management with NKE, by Dr. Christoph Leitl, president of the Austrian Chamber of Commerce. “All awarded companies are role models for others and demonstrate how new markets can be developed and potentials used,” said Dr. Leitl. Beside strong business performance, the selection criteria for the award include sustainable business development .
July
16
Fast bespoke plastic bearings igus has increased the scope of its speedicut rapid machining service to cover more materials and sizes of plastic bearings. The service was launched two years ago to provide customers with a fast and cost effective service for special parts, prototypes and low volume parts, which can be delivered within 24 hours. The services now covers a wide range of tribo-polymer materials with more sizes available, including stock sheet in various thicknesses. “As there are no minimum order quantities, speedicut is a cost-effective and easy way of producing custom-designed complex oneoffs, prototypes and low volume parts quickly,” says Rob Dumayne, director at igus. “As speedicut is a machining process, there is no tooling set up cost, which makes it extremely economical for low volume manufacturing.” The iglidur tribo-polymer materials used are self-lubricating and maintenance free with inherently low coefficient of friction, ensuring performance and reliability over a long service period. In addition, the life calculation programs offered by igus can be used to optimise material selection.
July
17
NN, INC. acquires Chelsea Grinding Company, Cylindrical Roller Manufacturer NN, Inc. announced that it has acquired the assets of Chelsea Grinding Company. Chelsea is a manufacturer of cylindrical rollers used primarily in the hydraulic pump industry. Chelsea, a privately-held company located in Jackson, Michigan, had sales of approximately $2.3 million in 2013. Its products are used mainly in roller vane pumps for the hydraulic pump market as well as torsion bars in the automotive market. NN will roll up Chelsea’s operations under its NN Metal Bearing Components Group.
July
19
Timken Offers Sheave Pac Bearing Assembly The Timken Sheave Pac bearing assembly is designed to eliminate the need to re-grease the traveling block or crown block on oil rigs. In the past, maintenance personnel performed the challenging task of re-lubricating the crown and traveling blocks situated hundreds of feet above the rig platform. The Timken Sheave Pac alleviates that job through its sealed-for-life sheave bearing assembly, helping to increase safety for rig workers and reduce expensive downtime.
July
21
Bearings Procurement Category Market Research Report from IBISWorld Has Been Updated Bearings have a buyer power score of 2.7 out of 5, representing a medium level of buyer negotiating power. Buyers benefit from widespread availability of the product; the ubiquitous nature of industrial bearings makes the purchasing process relatively easy. However, buyers are hindered by moderate and rising market share concentration. “The average price of bearings has been rising at a moderate, steady pace during the three years to 2014 due to rising downstream demand,” says IBISWorld procurement analyst Cameron Roark. “Strong and consistent increases in the industrial production index have boosted sales of bearings during this period, giving suppliers leverage to raise prices.” Additionally, the average bearings vendor generates high profit margins, encouraging larger vendors to acquire smaller suppliers to expand their market share. “This consolidation trend is increasing market share concentration and is forecast to further limit buyer negotiation power over the next three years,” adds Roark. Despite their dominance in the market, large vendors still contend with a moderate level of competition. High levels of import penetration, along with declining demand from federal defense, are encouraging suppliers to compete for business and have kept prices from rising at a faster rate, benefiting buyers to an extent. Page: 89
What Happened in the
Bearing Industry Second Half of
2014
Buyers can leverage the availability of other vendors, high import penetration and vendors’ high profit margins to obtain lower prices. Additionally, buyers can typically negotiate with vendors to secure discount prices when purchasing in bulk, especially when purchasing from large vendors that have high profit margins. Nevertheless, buyers are encouraged to enter into long-term agreements to lock in current prices before they rise further in the next three years. Contracts can reduce the price per unit and provide additional products or services. For more information, visit IBISWorld’s Bearings procurement category market research report page.
July
22
NTN Develops “Bearing Technical Calculation System for Machine Tool Spindles” NTN Corporation (hereafter, NTN) has developed the “Bearing Technical Calculation System for Machine Tool Spindles” as part of technical services designed for customers to enable them to quickly and automatically calculate precision rolling bearings used for machine tool spindles with characteristic values such as main shaft rigidity and bearing operating life. The newly developed “Bearing Technical Calculation System for Machine Tool Spindles” is capable of technical calculations for 10 different main shaft layouts, such as bearing type, arrangement and preloading methods. All customers need to do is enter data required for calculations, such as bearing type and usage conditions, into a special Excel® file template and send it to NTN by e-mail. Bearing rigidity, operating life and other characteristic values are automatically calculated on NTN’s designated server, and the results are returned quickly and automatically in what is the first system of its type in the industry.
July
25
NN, INC. Announces Definitive Agreement To Acquire Autocam Corporation
Transformative Acquisition Brings Additional Technologies, Product Launch Capabilities and Respected Autocam Brand to the NN Family NN, Inc. announced that it has entered into a definitive agreement to acquire Autocam Corporation for $244.5 million in cash, $25.0 million in stock and the assumption of $30.5 million in debt. The transaction is expected to be immediately accretive to earnings. The Company anticipates the transaction to close in the third quarter, subject to customary closing conditions and regulatory approval. NN was advised on the transaction by Page: 90
KeyBanc Capital Markets, Inc. Headquartered in Grand Rapids, Michigan, Autocam is a global leader in the engineering, manufacture and assembly of highly complex, system critical components for fuel systems, engines and transmission, power steering and electric motors. With expected 2014 sales of approximately $250 million, Autocam employs over 2,100 employees and has operations in 15 facilities in the U.S., Europe, South America and Asia. The expected 2014 sales do not include approximately $42 million in expected sales from a 49% Chinese joint venture Bearing News • Issue 3
accounted for under the equity method. With the close of the acquisition, the Autocam team will join NN’s Precision Metal Components Segment forming a new, dedicated Autocam products segment. As a result of the transaction, John Kennedy, Founder and CEO of Autocam will become a significant shareholder of NN. Additionally, it is the intention of the NN Board of Directors to consider Kennedy for a seat on its Board. The transaction does not include the Autocam Medical business. Richard Holder, President and Chief Executive Officer of NN, Inc. commented, “This acquisition brings together two respected brands – NN and Autocam. Sharing our technologies and expertise creates a much stronger team with the common goal of providing exceptional products, solutions and service to our customers. The combination of the Autocam team with NN’s Whirlaway and VS businesses results in a strong precision components business with unparalleled technical capabilities, processes, systems, and skilled program management along with superior product launch capabilities. Moving forward, we will continue to use the Autocam brand name to preserve its strength and reputation in the marketplace. Our teams are dedicated to ensuring a smooth and successful integration with uninterrupted service and products to all our customers.” Mr. Holder continued, “This acquisition is the next step in our ongoing strategy to aggressively grow our business through strategic, profitable acquisitions that provide complementary resources
July
29
and lines of business. The addition of Autocam to the NN family is a transformative event, creating a much stronger Company with greater opportunity to drive future growth and bring sustainable value to our shareholders.”
John Kennedy, President and Chief Executive Officer of Autocam Corporation commented, “We are very excited about joining the NN family. This is a compelling strategic transaction that will create enormous opportunities for our employees and a superior experience for our customers. This transaction will bring together NN’s and Autocam’s complementary core strengths and values and will position this business segment to outgrow its end markets by taking advantage of global market trends in fuel efficient technologies such as gasoline direct injection systems, high-pressure diesel injection systems and variable valve timing. The fact that the Autocam brand will continue after the completion of the transaction is an honor to the legacy of our company and our team of tremendously talented people.”
Klüber Lubrication Receives ISO 21469 Certification Klϋber Lubrication, a worldwide manufacturer of specialty lubricants, has received the National Sanitation Foundation (NSF) ISO 21469 certification at its Londonderry, New Hampshire facility. The certification from the NSF ensures food-grade lubricants from Klüber Lubrication are manufactured in a hygienic environment, using both best practices and the safest ingredients. Klüber Lubrication leads the industry with five global locations that are NSF ISO 21469 certified. ISO 21469 specifies hygiene requirements for the formulation, manufacture, use and handling of lubricants which, during manufacture and processing, can come into incidental contact with products and packaging used in the food, food processing, cosmetics, pharmaceutical, tobacco and animal‐feeding‐stuffs industries.
Page: 91
What Happened in the
Bearing Industry Second Half of
Aug
02
2014
Independent Test Study Demonstrates a 48.5% Increase in Service Life of Bearing Type HJ 208 With NanoLub® EP Grease Additive NanoMaterials Ltd., the innovative nano lubricants company and a subsidiary of the leading “Nanotech Industrial Solutions, Inc.” (NIS), continues to cooperate with bearing manufacturers to find new ways to improve the performance of various bearing applications. The purpose of an independent case study conducted by a leading European Bearings manufacturer was to measure the impact of Nanolub® EP Grease Additive on durability of Bearing type HJ 208. The tests were conducted on bearing type HJ 208, lubricated with Liton EP2 neat grease vs. same Liton EP 2 grease formulated with Nanolub® GH-X EP Grease Additive (4% treat rate). Both tests were conducted on 20 samples of HJ 208 bearings for each test and under the same test conditions. Nanolub® GH-X EP Grease Additive was shown to have a positive impact on bearing durability, with a 48.5% increase in bearing service life. The full case study can be downloaded here or sent out by request from NanoMaterials marketing department.
Aug
04
NSK Technology Centre under new management Volker Polonyi has been appointed the new director of NSK’s European Technology Centre (ETC) in Ratingen. He brings with him 27 years of experience in bearing and linear technology and has previously worked for NSK as a sales director for industrial bearings, a sector manager for wind power technology and as head of application developments, amongst other things. ETC workforce and technology has been greatly expanded in recent years. It currently employs 180 persons who are involved in both development and test work and who also inspect and approve vendor products and materials.
Aug
05
Taylor Hobson Offers Bearing Measurement Tool A precision surface measurement tool featuring an industry-leading high-speed column drive, precision positioning and 4 mm roundness and contour gauge has been introduced by Taylor Hobson, a unit of Ametek, Inc. The new Talyrond 500H measures roundness, profile and surface finish on a single platform with high accuracy due to an extremely low noise floor. It is ideally suited for high-accuracy measuring applications including precision bearings, fuel injectors, crankshafts and turbocharger parts. Numerous specialized accessories allow the instrument to accommodate the industry’s most demanding applications. It accurately duplicates a machine tool’s movements and exactly reproduces a work piece shape. This allows the Talyrond 500H to provide users with rapid feedback for efficient quality assurance. A low-noise metrology frame, accurate axis alignment and a patented data collection method provide it with unmatched straightness and roundness measurement capabilities. A high-resolution gauge measures linear or circumferential surface roughness.
Page: 92
A frictionless air-bearing spindle and precision column measure roundness, cylindricity and straightness. A patented calibration technique performs radius, angle, height, length and distance measurements. Simplified teach and learn programming techniques, comprehensive user prompts and on-screen instructions combine for easy, error-free operation. It performs calibration, center and level functions along with measuring routines automatically. Bearing News • Issue 3
Aug
08
RKB at Expo Usipa 2014 in Ipatinga (Brazil) The RKB Group of Switzerland, in cooperation with its Brazilian partner, attended the 26th edition of Expo Usipa, which took place in Ipatinga, the municipality located in eastern Minas Gerais state of Brazil. The trade show is well known for providing a distinctive venue for companies wishing to exhibit their technical products for the local mines and minerals industry. The high turnover of visitors revealed once again the strong interest of the Brazilian market in the value-added products of the Swiss Group.
Aug
09
Acorn Set Themselves Apart By Becoming The Largest Stockist Freudenberg Sealing Technologies In The UK market share here.”
Acorn Industrial Services, has announced that it has secured a UK distributorship with Freudenberg Sealing Technologies and will be stocking their Simmerrings range of rotary shaft seals, to further its growth and expansion plans. Freudenberg Sealing Technologies (FST), incorporating formerly Simrit and all other Sealing Sectors of the Freudenberg group, is renowned for manufacturing top quality mechanical seals for generations. FST only seek suppliers who share their commitment to customer satisfaction and continuous quality improvement. As part of the supply chain, Acorn Industrial Services are dedicated to upholding this ethos.
The deal will see Acorn providing the full range of FST rotary seals. As the leading technology leader in rotating shaft seals, ordering this Range through Acorn, customers can be assured that they will receive an extremely reliable and durable product. Customers will also be able to order the seal range directly from the Acorn Express online portal. Gavin continues: “We believe it’s just as important for customers to fit a high quality seal as it is to fit a high quality bearing. Our customers now have an authorized route to buy premium quality seals and bearings.” Martin White, distribution sales manager for Freudenberg Sealing Technologies added: “Acorn is well regarded as a supplier of premium brand products and high quality service. We look forward to a long and successful relationship together.
With more than 80 years’ experience in the sealing business, FST has grown to become the global leader in sealing technology and innovation, offering the best cost to benefit radio in the market.
To sustain the company’s award winning customer service, FST rotary seals will be available for same day dispatch, along with over one million other items Acorn hold in stock throughout their eight miles of shelving.
Gavin Stacey, Sales Manager at Acorn Industrial Services, reveals: “This is exciting news for Acorn and for our customers. By keeping Freudenberg seals in stock, we believe it’s a great opportunity to significantly increase their
Acorn has 30 years’ experience in the supply of bearings, linear systems and power transmission products, delivering a fast response for local, national and international customers.
Page: 93
What Happened in the
Bearing Industry Second Half of
Aug
11
2014
New AEGIS® iPRO-MR Monitoring Ring Combines Shaft Grounding and Shaft Current Monitoring for Critical Applications
2014 Electro Static Technology’s new AEGIS® iPRO-MR Ring combines shaft voltage bearing protection with continuous monitoring of shaft voltage levels from a remote location—all in real time. The AEGIS® iPRO-MR is an AEGIS® Shaft Grounding Ring and a shaft monitoring ring in one, ensuring optimum uptime and reliability of large motors and generators in critical applications. The iPRO-MR is ideal for the protection of motors in remote locations that cannot be easily monitored or maintained. For complete details on the iPRO-MR Shaft Grounding/Monitoring Ring, visit http://www.est-aegis.com/iPro-MR.htm.
Aug
14
Boca Bearing Company Launches Global Contest to Recognize Artists, Scientists, Technologists, Engineers and Mathematicians Involved in Innovation The Boca Bearing Company, one of the most trusted names in ceramic bearing and lubrication technology, announced that they will again be sponsoring The Innovation Contest for 2014. Over $10,000 in cash and prizes will be awarded for innovative, mechanical projects that they submit to the contest. Boca Bearing Company believes in supporting innovators who push the limits of new technologies that will drive the future economy. Contest winners will be chosen based on a video submission of their innovative, progressive or overall “cool” projects that utilize ball bearings, roller bearings or linear bearings. One finalist will be chosen by the voting public each month to win a GoPro3 Camera, and the Grand Prize winner will be chosen by the Boca Bearing Company to receive a grant check for $5,000. The two Runner Ups, chosen by Boca Bearing Company, will each win their own 3D Printer. ($2,700 value each).
Aug
15
Thomson Expands Range of High Performance Miniature Linear Motion Component Offering Thomson Industries Inc., a leading manufacturer of linear and rotary motion solutions, has expanded its range of high performance, miniaturized components with the launch of several new products. The new precision TSI Rolled Ball Screws offer high load capacity, smoothness, and quiet operation which can be easily customized. Thomson’s unique design offers up to two times more load capacity than alternate ball screws, resulting in longer life and better return on investment. Screws are available in diameter sizes from 6 to 14mm, with flexible ball nut mounting configurations and precision rolled screws to T7 accuracy class.
Aug
16
SKF establishing Global Technical Center in United States to strengthen global network SKF announced plans to build a new 12,100 m2 (130,000 sq. ft.) facility in the greater Chicago area. The Global Technical Center Americas (GTCA) reinforces SKF’s strategy to have these Centers near its important customers to focus on market specific product innovations, leveraging all of SKF’s five
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platforms – bearings, seals, mechatronics, lubrication systems and services. It joins two centers recently opened in China and India, while the two new European centers are under construction, one in Holland and one in Sweden.
Bearing News • Issue 3
Aug
Aug
Aug
17
Timken and Meggitt MRO Shop Team Up on First Aerospace Bearing Certification
19
Michael Preinerstorfer In Charge Of Industrial Business For Nsk Europe
20
BearingNEWS launches KOREA portal
The Timken Company congratulates Meggitt Aircraft Braking Systems in Akron, Ohio, for becoming the first aerospace bearing maintenance facility to receive Timken Bearing Certification. Timken presented the certification signifying the MRO (maintenance, repair and overhaul) shop adheres to Timken standards for bearing removal and handling, cleaning and inspection, analysis of bearing damage, bearing setting and adjustment, and bearing storage. Timken® bearings are installed on Meggitt aircraft landing wheels.
Michael Preinerstorfer is, since August 1st 2014, the newly appointed Managing Director of NSK’s European Industrial Business Unit (EIBU). The world’s third-largest manufacturer of bearings has centralised its European activities - in the field of bearings and linear technology - for industrial applications in this Ratingen-based business unit.
BearingNEWS launches KOREA portal BearingNEWS is expanding her local Bearing Industry portals with BearingNEWS Korea. The main goal is to keep the South Korean industry informed regarding the latest developments in the bearing industry. The BearingNEWS online portals are already published in 7 languages since 2013. Bearing industry product updates, engineering know-how, company news, market insides and exhibition announcements will be published in Korean language through the portal kr.bearing-news.com from now on.
Aug
20
Boca expands the line of Radial PEEK Ceramic Hybrid Bearings The Boca Bearing Company is proud to announce the expansion of their line of PEEK Radial Hybrid Bearings. PEEK is a semicrystalline thermoplastic with excellent mechanical and chemical resistance properties that are retained in high temperatures.
PEEK Bearings are washdown safe, offer great chemical resistance, have very low moisture absorption, and are unaffected by continuous exposure to hot water and steam. Peek bearings are often used in the food and beverage industries in additional to medical applications. PEEK is corrosion resistant, and non-magnetic. Page: 95
What Happened in the
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Aug
21
2014
NHBB: Market Specialization Drives Sales Force Reorganization In order to facilitate more specialized knowledge of markets and customers, the North American field sales team for NHBB has reorganized into two groups - the Aerospace and Defense Group, and the Medical Device and Industrial Group. The Aerospace and Defense Group is responsible for selling all of NHBB’s high precision products to major aerospace manufacturers - aircraft and engine OEM’s and Tier 1/2/3 customers - and defense contractors and subcontractors.
Aug
23
New Inpro/Seal® mini66(TM) Bearing Isolator Provides Permanent Bearing Protection in Applications with Limited Space Inpro/Seal, the company that invented the Bearing Isolator, is proud to announce the newest innovation in Bearing Isolator technology, the mini66. The mini66 is the smallest Bearing Isolator available to be rated IP66. With only a 0.375” (9.52mm) overall length, the mini66 protects against both water and dust ingress on applications with very limited space. This latest advancement in Bearing Isolator technology allows for permanent bearing protection on a wider range of rotating equipment than ever before. For more information about the mini66, only from Inpro/Seal, visit www.inpro-seal.com/mini66
Aug
Aug
25
SKF appoints new Press & Media Relations Director
27
Bearings Limited become Master Distributor Of Silverthin Bearings
Theo Kjellberg has been appointed Director Press & Media Relations within the SKF Group, starting 25 August 2014.
Bearings Limited announced it is now an official North American Master Distributor of Silverthin Bearings. Silverthin Precision Thin Section Bearings and Slewing Rings will be available to Bearings Limited customers for immediate shipment. Marketing and Sales support materials will be available to customers by request through Bearings Limited. Bearings Limited continues to increase Page: 96
its distributed brand portfolio by partnering with Silverthin. Positioned as a world class manufacturer of thin section ball bearings and slewing ring bearings, Silverthin will greatly enhance the Bearings Limited value propositions. The Silverthin product offering includes a complete line of slewing ring turntable bearings and a wide range of thin section ball bearings for the commercial, industrial, aerospace, and military markets. Bearing News • Issue 3
Aug
29
Liebherr introduces Bearings for Multiple Applications Liebherr is a leading global manufacturer and supplier of large diameter bearings and has almost 60 years of experience in the development, design and manufacture of ball bearing slewing rings and roller bearing slewing rings. Large diameter bearings are produced in facilities located in Biberach an der Riss, Germany, and Monterrey, Mexico, in various dimensions and designs in accordance with customer specifications. The current product range includes large diameter bearings, which may be single row or double row four-point contact bearings, triple row roller bearings or special bearings. Liebherr currently manufactures and supplies bearings with a diameter range of 16 to 236 in. (40 to 600 cm). Other sizes may be available on request.
Sep
01
GGB Extends Range of Self-Lubricating Sintered Bronze and Sintered Iron Bearings GGB Bearing Technology, formerly Glacier Garlock Bearings, now offers an extended range of self-lubricating sintered bronze and sintered iron bearings. The bearings from the METAFRAM® series were developed for applications with high sliding speeds, which require low friction and resistance to frequent start/stop operation and corrosion. They are well suited for applications where conventional lubrication is not possible, and can replace existing lubricated bearings. Manufactured by compressing metal powder under high pressure, the sintered bearings have a porous structure that can be impregnated with lubricants. The standard bearing materials in the METAFRAM® sintered bronze series include GGB-BP25™, GGBFP20™ and GGB-SO16™ which are available in a standard assortment of cylindrical bearings and flanged bushes.
Sep
02
Taper Roller Bearing Capability and Production Increase for North America Physical plant expanded and automation efficiency increased to help support burgeoning demand of North American market The C&U Group, parent company of North American subsidiary, C&U Americas, has announced a major expansion of its Taper Roller Bearing plant facilities and overall production capabilities at the company’s Tainai complex, which is located in the Fengxian District near Shanghai. C&U is China’s
Fully automated production lines and added capabilities at C&U’s Tainai facility near Shanghai will help C&U Americas meet the demands of a rapidly growing North American market.
largest bearing producer and one of the
world’s top 10 bearing manufacturers. Fully automated production lines and added capabilities at C&U’s Tainai facility near Shanghai will help C&U Americas meet the demands of a rapidly growing North American market. A key objective of the expansion is to help meet the demands of C&U’s rapidly growing North American market. In making the announcement, William A. Childers, President of C&U Americas, noted, “The added capabilities of the Tainai facility are just what we need to keep pace with our successful growth in the U.S. market and aggressive plans to expand our bearing business throughout the entire NAFTA region.” C&U’s Tainai facility was established in 2004 and started producing both singlerow and double-row taper roller bearings in 2005. In 2012, a second plant was added and the facility began to incrementally increase bearing production capacity. Overall floor space has been increased by a factor of four from 3,799 square meters to 15,100 square meters. The production lines have been doubled, giving the ISO/ TS16949 certified plant 18 operational lines. All of the new lines are fully Page: 97
What Happened in the
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2014
C&U portfolio includes over 30,000 types of bearings in a wide range of specifications and sizes ranging from 1.5mm ID to 4000mm OD. C&U offers a full line of taper roller bearings in a wide range of sizes.
Overhead view shows major expansion of plant facilities and overall production capabilities at the company’s Tainai complex.
automated. Overhead view shows major expansion of plant facilities and overall production capabilities at the company’s Tainai complex. Targeting over 2.2 MM bearings per month The Tainai plant expansion is an ongoing process and more production lines will be added over the next five years. This will more than double the current capacity. When the expansion is completed, the plant will be operating a total of 39 production lines and delivering over 2,260,000 taper roller bearingunits per month. Editor note: C&U Americas was established in 2009 in Plymouth, MI. In 2013, the company moved its North American HQ and warehousing facility to larger quarters to increase inventory capacity and make it easier to distribute bearing products to OEM and aftermarket customers in the automotive and industrial markets. C&U Americas offers a full line of bearing types and styles for use in original equipment manufacturing, aftermarket replacement, and MRO operations. The
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C&U offers a full line of taper roller bearings in a wide range of sizes.
As China’s largest bearing producer, and one of the world’s top 10 bearing manufacturers, C&U utilizes the formidable production capabilities of its nine manufacturing centers, 34 bearing plants, and 22 vertically integrated component plants to produce over 2.8 million bearings per day. C&U relies on state-of-the-art manufacturing and stringent QC in order to maintain its leadership position in the bearing market. C&U Bearings are precision made in advanced manufacturing facilities that are independently certified for ISO9001 Quality Management System, QS9000/ VDA6.1 Quality Management System, ISO14001 Environmental Management System and SO/TS16949: Quality Management Systems. From its North American headquarters in Plymouth, Michigan, C&U Americas is able to offer its NAFTA customers exceptional value along with complete application engineering and customer service support.
Bearing News • Issue 3
Sep
03
NTN Exhibits at World Sugar Expo NTN run a booth at the world’s largest sugar industry exhibition “World Sugar Expo 2014” with the theme “Longevity, Toughness, Cleanliness.” The NTN booth features the ULTAGE series spherical roller bearings, as well as various bearings such as bearing units and Constant velocity joints for industrial machines.
Sep
Sep
Sep
04
Menon Bearings Ltd appoints Director
05
Minebea Launches Ball Bearing Joint Venture in China
08
OAV Air Bearing Introduces Roller Air Bearings
The Board of Directors has appointed Mrs. Nazura Ajaney as an Additional Independent Director of Menon Bearings Ltd for a period 5 years w.e.f. September 04, 2014 till September 03, 2019 subject to approval of shareholders at the ensuing Annual General Meeting of the Company.
Minebea Co., Ltd. announced that its Chinese subsidiary, Minebea Electronics & Hi-Tech Components (Shanghai) Ltd., established a ball bearing manufacturing and sales company in China’s Zhejiang Province jointly with a Chinese precision bearing manufacturer.
OAV Air Bearing is the leading manufacturer for rotary air bearings. In some cases there is a need for precise rotary air bearings to measure torque on a spindle. In some cases there is a need for smooth motion or a need to eliminate downtime to replace or maintain a standard bearing periodically. OAV Air Bearing solves these issues along with many others such as friction, vibration, oil or heat, and the list goes on.
replacement, eliminating the need for costly installation.
OAV Air Bearings have emerged as a very important element to precision technology. Many questions and concerns arise when determining how to implement air bearings to an existing unit. OAV Air Bearing has a solution.
• Outer diameter grooves allowing for light press-fit or epoxy for easy installation
OAV Air Bearing brought Roller Air Bearings into the market. This is the most convenient of all rotary air bearings. Perfect for spindle applications or any application which requires smooth and precise rotation. OAV Roller Air Bearings are unique and the only product of its kind. The Patent Pending product is designed to fit exactly the same way as a standard roller bearing would – the same size and very simple light press-fit method of installation. This makes it very easy for a direct
OAV’S innovative design includes an allin-one package with the core air bearing and face collars in one product. Therefore, the air bearing is already pre-aligned and tuned for maximum performance.
OAV Roller Air Bearing Features • All-in-one design. Includes face collars built into the bearing
Advantage of OAV Roller Air Bearings • More robust design since no porous material is exposed • Easy to install, replaces conventional bearings • Compact design • Uses standard bearing tolerances for light press-fit • Easy to fit into most assemblies without additional modification • Precision-frictionless technology • More effective at blocking oils/ contaminants from the environment • Reduced air consumption Page: 99
What Happened in the
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2014
Advantage over rolling element bearings • No Friction • Indefinite Operating Life • No Maintenance Required • No Heat Generation up to 140,000 RPM -High Accuracy
• Easy Installation • Can often replace conventional bearings • High Stiffness • More resistant to shock loads • Operates over wide range of temperatures • No Noise
• High Speeds
• Resistance to Dirt
• Clean Air
• Self-lubricating Material
• Reduced Vibrations
• Corrosion Resistant
• Damping Effect
Ay
09
Napoleon Engineering Services to Showcase Custom Bearing Manufacturing, Inspection and Testing Capabilities at IMTS 2014
Napoleon Engineering Services to Showcase Custom Bearing Manufacturing, Inspection and Testing Capabilities at IMTS 2014 The ISO9001:2008 and AS9100C certified Napoleon Engineering Services (NES) announced that it will be showcasing its custom bearing manufacturing, bearing testing, bearing inspection and bearing test rig manufacturing capabilities at the forthcoming International Manufacturing Technology Show (IMTS 2014), September 8-13 in Chicago, Illinois. Held once every two years at McCormick Place, IMTS is one of the world’s largest industrial tradeshows, covering bearings, motors, drives, machine tools, controls, computers, software, components, systems and processes. Historically, the show has attracted 1,900 unique exhibitors and 100,000 visitors from around the world. NES representatives at Booth E-5803 will be available throughout IMTS 2014 to discuss the company’s newest bearing product and service Page: 100
offerings, including:
Custom Bearing Manufacturing: NES designs and manufactures highprecision custom ball and roller bearings using superelastic Ni-Ti alloys; wear-resistant, high-life materials and coatings; and advanced design technologies, in both small and large quantities, with competitive lead times. Key specialty areas of NES custom bearing manufacturing include:
Active magnetic backup bearings for active magnetic bearing (AMB) systems. Here, the custom bearings serve as a high-reliability secondary failsafe system for a primary AMB within power generation, petroleum refining, machine tooling, natural gas pipeline, and critical industrial applications. When using AMB to support a rotating shaft, any reduction or loss of power could cause the shaft to drop. With an AMB backup bearing system, the shaft will drop 0.002” to 0.003” onto the back-up bearing
Bearing News • Issue 3
system itself, allowing it to coast to a stop without causing damage to the shaft or surrounding machinery. With available sizes from 1” to 14” OD, NES AMB back-up bearings incorporate wear-resistant materials, conventional or dry film lubricants, and a variety of cage and internal design characteristics. All of these combine to help manage the safe coast down of the rotating shaft. Depending upon application loads, full ball complement or caged bearing designs are specified. Some applications require more extreme design considerations, including special heat treatment processes, yielding very stable parts with extremely low residual stress. Other requirements allow for highly modified standard bearings with very short customer lead times.
Aerospace custom bearing manufacturing Aerospace bearing manufacturing typically requires the use of superior quality raw materials; the incorporation of extensive design and project review processes; and support for any required material or process traceability. To meet these needs, NES offers complete design, development and manufacturing of custom high-precision aerospace ball and roller bearings, as well as custom bearing modification. The manufacturing process includes close collaboration with an aerospace OEM’s own in-house engineering team, with full project management support from initial concept thru to final delivery. Typical requirements range from all stainless steel full complement bearings; to M50 long life angular contact ball bearings; to superelastic Ni-Ti alloy designs which incorporate wear and corrosionresistant, high-life materials and coatings. Supported applications include satellite and UAV and satellite arm actuation, antennas, fuel pumps, ram air turbines, transmission systems, turbine engines, and rocket engine valves. Expedited lead times are available upon request.
Corrosion resistant ceramic hybrid bearings Typical bearings that are specified for oscillating applications are prone to concentrated, magnified and accelerated wear on bearing rolling elements and raceways, since the oscillatory motion isolates bearing stress into localized areas and creates lubricant trapping. For higher speed and oscillatory applications, NES manufactures a variety of ceramic hybrid bearing sizes and types, incorporating specialty materials and coatings. NES custom ceramic hybrid bearings incorporate a silicon nitride material for reduced weight. This reduces the applied loads caused by centrifugal forces, with greater stiffness and lower frictional characteristics. The material also reduces heat generation and decreases operating temperatures. Silicon nitride bearings have excellent corrosion resistance for extended life. They also offer a lower thermal expansion coefficient, as compared to steel, for reduced thermal gradient effects across the bearing. For reliable operation within highly acidic environments, these corrosion-resistant bearings can run effectively in marginally lubricated applications at both high and low speeds, making them suitable for demanding manufacturing and vacuum system environments, as well as for use within corrosive saltwater and washdown applications.
Bearing Modification: NES also offers custom OEM bearing modifications to help meet specific application requirements. Bearing modification can be a time and cost savings alternative for many OEM’s. Some of the more popular modifications supported by NES include re-greasing, preload and endplay grinding, radial clearance changes, tapered roller bearing spacers, anti-rotation slots, oil holes and grooves, and tapered bore grinding.
Bearing Test Rig Manufacturing: Page: 101
What Happened in the
Bearing Industry Second Half of
2014
NES custom bearing test rigs support OEM aerospace, automotive, offhighway and industrial automation R&D requirements. The in-house capability for an OEM to perform its own rigorous bearing testing, via the use of its own rig, can reduce time-to-market and lead to new advancements in the OEM’s own mechanical bearing components and finished product technologies. NES can design and manufacture custom rigs for the testing of any sized ball or roller bearing, including four-ball and NASA five-ball rolling element testing. NES’s own in-house testing programs focus on three main aspects of testing; life (dynamic), environmental, and impact/ static testing. This expertise is carried over into the design and development of the customer’s own robust bearing test rigs. Customers can choose from a variety of test platforms and control options, in support of classical, sudden death, or maximum likelihood bearing test methodologies. NES engineers are available to evaluate customer intentions for bearing testing and to develop a 3D model and control option proposal for customer review of a prototype. Bearing test rigs can be constructed to test for any number of parameters, including bearing or lubrication efficiency, rolling contact fatigue, environmental conditions, application reliability, or supplier comparison. They can also be designed with manual controls for constant operating parameters or with full automation for step-stress duty-
Sep
13
cycle testing. Common monitoring and control features include bearing vibration, temperature, torque, rotational speed, applied load (axial, radial or moment), lubricant flow rate, oil inlet temperature, and thermal operating conditions. Test platforms can be designed with as many as eight test locations to maximize sampling rates and statistical accuracy, while still minimizing test time and overall budget.
Bearing Inspection and Bearing Testing Services: In addition to the aforementioned capabilities, the Olean, New York-based NES is also home to North America’s largest independent bearing inspection and bearing testing facility. This includes over 40 bearing test rigs. In-laboratory capabilities include bearing failure analysis and metallurgical testing; bearing stress analysis, including source qualification inspection (SQI); environmental testing; RCF and dynamic life cycle testing; impact and static load testing; first article inspection, per AS9102; and the reverse engineering of aircraft bearings for PMA-FAA Certification requirements. For more information about Napoleon Engineering Services and its bearing technology offerings, visit www. nesbearings.com.
KSB Pumps signs distributor Canadian Bearings KSB Pumps Inc. has inked a new sales and distribution partnership with Canadian Bearings, a Mississauga-based supplier of industrial systems and products. Canadian Bearings will be an additional sales channel for KSB products, especially the “Movitec”, “Eta”, and “Amarex N” series pumps in addition to KSB’s pump service capabilities.
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Bearing News • Issue 3
Sep
15
SwRI Launching Consortium to Develop New Dynamic Bearing Test Rig Southwest Research Institute® (SwRI®) has announced the formation of a consortium for joint research into new technologies to evaluate engine bearings for internal combustion engines. The objective of the Dynamic Bearing Rig Consortium is to design, demonstrate and validate a dynamically loaded bearing test rig that can replicate the variable loads critical to how bearings perform in an operating engine under transient and steady-state conditions. Simple bearing test rigs are widely used by bearing manufacturers, primarily to evaluate material properties. “They can be quite effective for comparing the load-carrying capability, scuff resistance and several other variables between two bearings,” said Kevin Hoag, a staff engineer in SwRI’s Engine, Emissions and Vehicle Research Division. “However, simulating the actual operating conditions inside an internal combustion engine is far more difficult.” Those evaluations currently require an engine test cell, which means high costs, limited instrumentation capabilities and a complex operating environment in which oil degradation can occur from many sources, making it difficult to isolate a particular variable for study.
Sep
18
SwRI engineers, using internal research funding, have already completed preliminary design work and concept evaluation on a dynamic bearing test rig that allows the operator to specify and control the load and engine speed-versustime (crank angle) to which the bearings are subjected. Under the aegis of the new consortium, researchers will construct a test rig based on that initial design, demonstrate its operation and ability to meet measured parameters that mirror engine operating conditions, and further develop it into a useful tool for designing and testing engine bearings as well as lubricants. Membership in the consortium means that manufacturers and suppliers of engines, bearings and lubricants can share pre-competitive research results without having to shoulder the full price for developing a new-generation bearing test rig. A kickoff meeting for the consortium is scheduled Sept. 24 at SwRI’s headquarters in San Antonio. Membership is $49,900 per year for the multi-year consortium. For more information contact Hoag at (210) 522-2637 or kevin.hoag@swri.org, or visit www.dynamicbearingrig.swri.org.
SwRI Launching Consortium to Develop New Dynamic Bearing Test Rig Klüber Lubrication, a worldwide manufacturer of specialty lubricants, has introduced Klübersynth GE 461200, a synthetic long-term gear grease for a variety of gear applications, and Klübersynth UH1 6 Series, a complete line of polyglycol gear oils available in ISO VG from 100-1,000 for a variety of industries, including food processing and pharmaceuticals. Klübersynth GE 46-1200 grease, ideal
for temperatures ranging from -30°C to 120°C, has a high load-carrying capacity and protects against wear and corrosion. The grease, which does not contain lead or solid lubricants, was developed to lubricate spur gears, bevel gears and worm gears with material pairings steel on steel, such as gear motors, small gears and gears in power tools. Klübersynth GE 46-1200 is also designed to lubricate toothed couplings, ball and roller guides, and rolling and sliding bearings. Page: 103
What Happened in the
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Sep
21
2014
Shanghai International Bearing Exhibition “Bearing 2014”
The Shanghai International Bearing Exhibition “Bearing 2014” is held on September 18 (Thu) to 21 (Sun), 2014 in the Shanghai World Expo Exhibition & Convention Center.
connection between production/demand and a series of technical seminars was held in Chinese language.
Different from the previous years many high-tech and class A brand manufacturers such as NTN, NSK, JTEKT, HIWIN, SKF, Minebea, and grease producers Klüber, Mobil and Shell took part to display their products and services. Also NN Inc., the premium class bearing ball and cage producers took part for the first time to the Shanghai International Bearing Exhibition.
Standard Bearings, Special bearings, Bearing Components, Bearings Grease, Lubricates and related Chemical Products
The fair was divided into 3 main Halls where 700 exhibitors and 50000 visitors came together according to the CBIA (Chinese Bearing Industry Association). Except the exhibition, a Bearing Summit Forum in order to discuss the trends of bearing market, case studies and the
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The exhibitors could be divided into the following groups:
1. Bearings and related products:
2. Equipments: CNC Lathe, Grinder & Super-finishing Machine, Metal Forming Machine, Cold Rolling Machine, Hot Rolling Machine, Heat Treatment and Surface Treatment equipment, Inspection, Measuring, Gauging and Testing Equipment, Other Machine Tool Auxiliary Equipment
3. Others: Abrasive Product, Cutting Tool, WorkHolding Devices & Related Products, Information and Consultation Services
Bearing News • Issue 3
Sep
22
NTN Exhibits at Chinese International Bearing Exhibition “Bearing 2014” NTN run a booth at the Chinese International Bearing Exhibition “Bearing 2014” with the theme “Proposing state-of-the-art technology and contributing to Chinese industry.” The NTN booth feature the ULTAGE series, as well as a wide range of products such as the maintenance tools. The section with exhibits for construction machinery bearings will feature a miniature hydraulic excavator model in the center, and introduce various products by applications.
Sep
23
ZKL introduces novelties in railway segment at InnoTrans fair in Berlin German tradesmen and customers. The fair participation should also help it.
More than 2/3 of ZKL concern production is destined for foreign markets. By reason of this the company concentrates on regular connection to clients by means of presentation at prestigious international fairs. Despite of gradually changing trends in the fair sector, the fairs still mean indispensable benefit for ZKL. Besides the possibility to present continually growing product and services portfolio to current customers, the worth and considerable respect is getting contacts for new clients and distributors. The plan for 2014 counts with the presentation at 10 prominent exhibitions and fairs all over the world. ZKL will cap this schedule at the turn of September and October participating at International Engineering Fair Brno. This long ago traditional „flash point of fair season“ will be foregone by the exposition at InnoTrans fair in Berlin from 23rd till 26th September 2014. In European matching German market is markedly important for ZKL. In the long term the concern target its activities on local marketing and services. The main aim is to approach their quality to
InnoTrans is international special fair for transportation engineering, innovative components, track vehicles and systems. In terms of this coverage ZKL will introduce here its novelties in railway segment. Foremost it is roller bearings with new plastic cabs suitable for regular railway service, that meet high international standards, are more resistant to mechanic derogation and their assemblage is simpler. Likewise the visitors could see the sealed roller bearings with plastic lubricant filling produced for RegioPartner train axles. The innovative spirit of ZKL concern can be found in tapered roller bearings unit
TBU with labyrinth seal and permanent plastic lubricant filling, which have not been produced in The Czech republic before. These bearings proved extremely high durability, which reached minimally 1 000 000 kilometers without any service or re-lubrication during testing up to the velocity of 200 kilometers per hour. In real operation we can count with durability overlapping several millions of kilometers.
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What Happened in the
Bearing Industry Second Half of
Sep
24
2014
NTN Exhibits at Chinese International Bearing Exhibition “Bearing 2014” NTN run a booth at the Chinese International Bearing Exhibition “Bearing 2014” with the theme “Proposing state-of-the-art technology and contributing to Chinese industry.” The NTN booth feature the ULTAGE series, as well as a wide range of products such as the maintenance tools. The section with exhibits for construction machinery bearings will feature a miniature hydraulic excavator model in the center, and introduce various products by applications.
Sep
29
Upgrade of Energy-Saving, Compact Hydraulic Unit “Power Meister” NACHI-Fujikoshi has expanded its product lineup and sales of energy-saving hydraulic unit products for use as drive sources for various machines and systems to achieve energy saving for machining lines. “Power Meister” released as a high-precision compact hydraulic system with its AC servo motor designed to directly drive a hydraulic pump in 2003 have been used in various fields requiring high controllability for controlling pressure of stamping presses, benders, clinching machines, injection molding machines and have made great contributions to higher performance of the machines as well as higher accuracy and quality of stamped or molded products.
Oct
Oct
01
ZKL Bearings’ present at Electra Mining Africa 2014
05
Schaeffler presents advanced powertrain engineering products and technologies at the Schaeffler Symposium
ZKL Bearings CZ a.s. introduced itself at the most important fair in the southern and mid African continent – at Electra Mining Africa 2014
To highlight the company’s most recent developments in its quest to achieve efficient future mobility, the Schaeffler Group is hosting the Schaeffler Symposium at the Max M. Fisher Music Center in Detroit. The theme for this year’s event is “Solving the Powertrain Puzzle,” as it addresses one of the hottest areas of automotive development due to the new and upcoming government mandates. The full-day event will focus on the latest developments in transmissions, with a special focus surrounding the challenges of engine development, through expert presentations, technical sessions, product demonstrations and networking. Kicking off the event is keynote speaker Dean Kamen, inventor, entrepreneur and a tireless advocate for science and technology.
Oct
07
RKB and ArcelorMittal renew bearing supply contract For the third time in a row, the RKB Bearing Industries Group has renewed with ArcelorMittal the contract for the supply of standard and technological rolling bearings over the next year. RKB is one of the four official premium global partners of ArcelorMittal for the provision of top quality bearings. RKB’s long experience
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and first-hand knowledge in designing, engineering and manufacturing rolling bearings for the metals industry are the main reasons for the renewal of the partnership between the two groups. Bearing News • Issue 3
Oct
Oct
09
NSK Adds High-Speed, High-Power Grease-Replenishing Spindle to Built-in Motor Spindle Series Featuring World’s Fastest Speed* of 25,000 min-1
11
OAV Air Bearing New Distributor Announcement
NSK Ltd. announced that it has added a high-speed, high-power grease-replenishing spindle that achieves speeds of 25,000 min-1 to its lineup. This new product achieves the world’s fastest speed for the spindle of machining tools, thereby making machining tools capable of higher speeds and higher levels of output.
Air Bearing product line, I.B. Kracht can now extend their capability to be able to fit their customers with the ultimate precision, smooth motion, no maintenance, and high-repeatability solution. OAV Air Bearings - the leading manufacturer of the recently advanced frictionless air bearing technology - is pleased to announce the addition of I.B. Kracht as Distributor of all of Europe. I.B. Kracht was founded in 1933 and specializes in sliding bearings, linear bearings, magnetic bearings and air bearings. With the addition of the OAV
Oct
15
OAV Air Bearing brings an Aerospace background to the design and manufacturing of precision porous air bearings. Because of this, OAV is very equipped to provide a solution which in many cases makes new technologies possible. OAV Air Bearings, made with 7075 Aircraft Quality Aluminum combined with special graphite, offer many benefits over traditional bearings.
Waukesha Bearings® Introduces Tilt Pad Thrust Bearings for High-Temperature ESPs At last month’s Pump & Turbomachinery Symposia, Waukesha Bearings featured its new Hidrax™ HT thrust bearing for high-temperature electric submersible pumps (ESPs). The Hidrax HT tilt pad thrust bearing can sustain unit loads of 8 MPa (1160 psi) at oil bath temperatures up to 300°C (572°F). Technological advances in steam-assisted gravity drainage (SAGD) are increasing ESP operating temperatures and placing increased demands on the thrust bearings located in the motor seal/protector section of the ESP string. “Waukesha Bearings is staying ahead of industry needs through our continual investment in research and development,” explained Chief Engineer Barry Blair. “With this high-temperature tilt pad thrust bearing, we are building on more than 30 years of experience in advanced materials development, testing and
implementation.” The Hidrax HT bearing is a drop-in replacement option for equipment requiring increased load capacity at high temperatures. The bearing is available in sizes up to 200 mm (8”), with center or offset pivot designs. Given the hardness of the Hidrax HT bearing surface, the rotating thrust collar surface must be hard as well. Waukesha Bearings can supply an appropriate thrust collar that is designed to work well with the Hidrax HT bearing. The Hidrax tilt pad thrust bearing platform is well-proven with polymer surfaces, with 200,000 supplied to date. Polymer Hidrax bearings have a rated unit load of 8 MPa (1160 psi) and oil bath temperature of 200°C (392°F). Page: 107
What Happened in the
Bearing Industry Second Half of
Oct
16
2014
Jamaica Bearings Company Named Exclusive Distributor Jamaica Bearings Company, a member of the Jamaica Bearings Group (JBG), Named Exclusive Distributor of Airtomic Sealing Rings by Sargent Aerospace & Defense.
support throughout the entire life cycle of each part.
Sargent and JBG, spanning a combined two centuries of service to the aerospace industry, have partnered together to provide sealing ring solutions to the commercial and military aftermarket sectors.
According to Mike Callaway, Airtomic Product Director , “Sargent is extremely excited to expand our relationship with Jamaica Bearings Company. The combined team will provide an opportunity to support the full life cycle of our customers’ hydraulic and pneumatic sealing ring requirements.”
Airtomic, a division of Sargent Aerospace & Defense, has named Jamaica Bearings Company (JBC), a member of the Jamaica Bearings Group (JBG), as Airtomic’s exclusive commercial and military aftermarket sealing ring distributor. Airtomic designs and manufactures pneumatic sealing devices, piston rings, and ducting solutions (including couplings) for aerospace engines, environmental control systems, airframe structures, and engine accessory components of commercial and military aircraft. Their products are custom designed and manufactured to specific customer requirements and their engineering team provides technical
Oct
18
This Airtomic agreement is the latest announcement by JBG in a series of awards. In 2013, Hoffman Performance Lighting (HPL) awarded JBG exclusive distribution rights for its PAR64 LED Landing Light, and Greene Tweed Company awarded exclusive military end-use distribution rights to JBG for its sealing solutions.
igus Demonstrating self-lubricating bearings and high-strength plastics for outdoor equipment at GIE+Expo
igus, manufacturer of self-lubricating plastic bearings, will be demonstrating the power of their plastic components at GIE+Expo 2014, the largest industry trade show for outdoor power equipment, lawn and garden equipment, and light construction and landscaping equipment. On display will be a selection of igus’ most reliable bearing materials for these types of applications, along with their igubal spherical rod-end bearings. Page: 108
“This agreement further expands our mutual partnership with Sargent,” shares Scott Carpenter, Vice President of Sales for Jamaica Bearings Company, “and it helps streamline the products offered to our customers .”
igubal rod end bearings handle high loads at normal room temperatures, have excellent dampening properties and weigh only a fifth of traditional metallic bearing rod end bearings, making them an excellent replacement for standard metal options. The resistance of igubal bearings to dirt and dust makes them ideal for applications where a standard greased bearing would not be suitable, such as in outdoor and agricultural applications.
Bearing News • Issue 3
Oct
19
Schaeffler opens its first manufacturing facility in Russia
The global technology company Schaeffler inaugurated its first manufacturing facility in Russia. The Schaeffler Group will deliver highquality products to domestic and overseas automobile manufacturers and the railway industry from its new production plant in Ulyanovsk.
Oct
19
Brazil bearings, gears and driving elements market production forecast to total R$8.5Bn by 2018 Demand for bearings, gears and driving elements increases 47% over review period to reach R$7.9 billion in 2012, mainly due to high car sales and Brazilian government incentives. Value of imports reaches R$3.9 billion in 2012, gaining share slightly to 52%. With 34% growth over review period, local manufacturers´ turnover reaches R$4.8 million in 2012. Manufacturers´ profitability reaches 9% of turnover in 2012, decreasing by four percentage points since 2007. Exports
Oct
20
Mikhail Volkov, General Director of Schaeffler Manufacturing RU (middle) proudly presents the symbolic key to the new plant in Ulyanovsk. Left: Dietmar Heinrich, CEO Schaeffler Region Europe.
see strong growth over 20072012, with the US and Argentina being Brazil´s largest trade partners. Production turnover over forecast period is expected to increase at 10% CAGR to reach R$8.5 billion in 2018.
SKF Solution Factory opens in Birmingham, Alabama SKF announces the opening of its latest SKF Solution Factory. Located in Birmingham, Alabama, the facility is designed to provide customers with a single point of access to SKF’s range of industrial and application knowledge. This is the third SKF Solution Factory to open in the United States and the sixth in North America. “With every SKF Solution Factory that we open, we bring SKF knowledge closer to our customers,” said Vartan Vartanian, President, SKF Industrial Market, Regional Sales and Service. “We have many customers in this part of the United States, from a wide range of industries, so it makes a lot of sense for the next step in our global expansion to take place here in Birmingham.”
The new facility offers an extensive range of SKF services and solutions, including application and reliability engineering, customized machined sealing solutions, mechanical services, asset diagnostic services and a full spectrum of training courses. This is the second SKF Solution Factory to open during 2014, taking the Group’s total to 29 across the world. Page: 109
What Happened in the
Bearing Industry Second Half of
Oct
24
2014
Kinetic Bike Bearings launches bearings boxes for cycle shops The newly formed cycle business Kinetic Bike Bearings (KBB) has created a range of compartmentalised bearing boxes aimed at bike shop workshops. The team behind KBB, which has been trading since February, said after spells in many different customer-facing roles within the cycle trade, found that dealers were increasingly frustrated in sourcing and stocking wheel, headset and full-suspension frame pivot bearings. KBB said: “Apart from the select few workshops out there, it was apparent that workshops weren’t pro-active in organising their bearing stocks in advance of service work, but instead sourcing bearings as and when the need arose. The firm is inviting bike trade dealers to www.kineticbikebearings.com and then follow the log in link to apply for a trade-only account and to view all the Workshop Bearing Boxes, as well as the individual bearings stocked.
Oct
26
NTN Exhibits at International Trade Fair for Packing “PACK EXPO International” NTN run a booth at International Trade Fair for Packing “PACK EXPO International” in Chicago, Illinois, with the theme “A Key Ingredient for Your Application.” The booth feature exhibits of bearing units and other products related to lubrication systems.
Nov
Nov
01
Auburn Bearing & Manufacturing Launches Website Redesign
04
Orkot Marine Bearings’ application in Maersk Triple E containerships
Auburn Bearing & Manufacturing, a company with over a 100+ years of experience, is pleased to announce its newly redesigned website that features not only its traditional ball thrust bearings but, also its custom manufacturing capabilities. The company offers standard, custom and difficult-to-find ball and roller thrust bearings in low-to-mid volume markets, as well as manufactures custom parts.
Orkot Marine Bearings, developed and manufactured by Trelleborg Sealing Solutions, contribute to the build of one of the world’s most efficient and largest containerships, the Maersk Triple E class family, built by Korea’s Daewoo Shipbuilding. Orkot TXMM and TLMM bearings were developed to meet the requirements of ever changing markets. The synthetic composite bearing materials incorporate solid lubricants to provide exceptional wear resistance, virtually no swell in water and great dimensional stability, the manufacturer said. The bearings have been chosen by Maersk for its Triple E class family of containerships.
Nov
06
Bearing grease from Klüber improves on friction and wear
Klüber Lubrication, a worldwide manufacturer of specialty lubricants, has introduced Klübertherm HB 88-182 for the long-term lubrication of rolling bearings. This pioneering lubricating grease offers excellent high-temperature properties and can be used for low loads combined with high speeds and high loads combined with low speeds. It is fully synthetic and based on a thermally stable base oil, polytetrafluoroethylene Page: 110
(PTFE) thickener and special additives. Klübertherm HB 88-182 protects more effectively against friction and wear than other high-temperature greases, proven in the field and on FE8 and FE9 rolling bearing testers. Bearing News • Issue 3
Nov
07
Thordon Bearings Announces Distributor Changes in Europe Thordon Bearings Inc. of Canada is pleased to announce that Duwel Group will be the new, authorized Thordon distributor for Norway, United Kingdom, and Finland. Duwel has been active in Sweden for over 22 years and is ready and capable to provide high quality sales and service support in these countries. Duwel Group has established three companies to represent Thordon. In Norway, Duwel Norway AS will replace Scanco; in the U.K., Duwel UK Ltd. will replace the AND Group; and in Finland, Marmex AB/Duwel Finland AB will continue operations there as part of the Duwel Group. Websites for all companies can be found at www.duwelgroup.com This strategic move transforms Duwel Group into the stocking distributor for the world’s largest manufacturer of non-metallic oil and grease free bearing systems. Duwel will be offering Thordon Bearings products with the highest level of service and knowledge that they are acclaimed for in Sweden.
Nov
10
Federal Mogul invests USD 20 mln in factory in Romania US group Federal Mogul will invest over USD 20 million in its friction pads factory in Ploiesti, Romania, taken over this year from Honeywell, reports local Wall-street.ro. The investments in Ploiesti will target two new production lines, one that will start production in 2015, and another one that will become operational in 2016. The plant currently operates two production lines. The third one will be intended for personal vehicles, while the fourth one will be for commercial vehicles. Federal Mogul employs 270 people at its factory in Ploiesti and plans to increase the number to 340 by end-2015, according to Nevill Rudd, vicepresident within Federal Mogul.
Nov
11
Schaeffler UK plant achieves two-year accident-free target Schaeffler UK has achieved its target of two years (more than 850,000 working hours) of accident-free production at its automotive engine component plant in Llanelli, South Wales. Schaeffler UK’s world class manufacturing plant produces precision engine components including general bearings and mechanical tappets for the automotive industry. The plant, which was established in 1957, employs 250 people including an annual intake of four apprentices.
Nov
12
NTN Exhibits at China’s Largest International Trade Fair for Construction Machinery “bauma China 2014” NTN run a booth at China’s Largest International Trade Fair for Construction Machinery “bauma China 2014” with the theme “Proposing the state-of-the-art technology — Passing on technology to the next generation and ongoing development.” The booth feature exhibits of the ULTAGE*1 series spherical roller bearing, as well as large size tapered roller bearing and Filter Seal Integrated Large Size Bearing to propose longer operating life and more compact in size. Other exhibits include the IC Tag Integrated Bearing, Integrated Rotation Sensor Bearing and angle sensor unit that utilize sensor technology, as well as maintenance tools and other products for the aftermarket.
Nov
18
Timken Continues to enlarge Its Bearing Portfolio with the acquisition of Revolvo Ltd
The Timken Company announced it has reached agreement with ERIKS NV to acquire the assets of Revolvo Ltd., a specialty bearing company based in Dudley, U.K. Revolvo makes and markets ball and roller bearings for industrial applications in process and heavy industries. The company’s split roller bearing housed units are widely used by mining, power generation, food and beverage, pulp and paper, metals, cement, marine and waste-water end
users. In 2013, Revolvo posted sales of approximately $8.3 million. Timken has been steadily adding to its product portfolio as part of its growth strategy and over the past three years has acquired a number of new products and services including roller and engineered chain, lubrication systems, and gearbox, generator and motor repair services. The company sees Revolvo as both highly complementary and integral to filling out the Timken bearing product lines. Page: 111
What Happened in the
Bearing Industry Second Half of
Nov
19
2014
SKF invests in new lubrication systems factory in the Czech Republic SKF is inaugurating its expanded lubrication systems manufacturing facility in the Czech Republic. The expanded factory has been designed with a focus on reducing the building’s overall environmental impact, including more efficient energy and water usage and choice of more sustainable building materials. SKF has made significant investments in expanding its lubrication systems business in recent years, since the acquisitions and integrations of Willy Vogel AG and Lincoln International in 2004 and 2010, respectively. The Group now offers the lubrication industry’s broadest range of products and services, under two leading brands: Lincoln and SKF.
Nov
20
RKB opens new plant for small size bearings The RKB Group has finalized the opening of the new MS Plant dedicated to manufacturing miniature and small size ball bearings. The new facility encompasses over 8.000 sqm and features 36 fully automatic production lines, which operate in strictly controlled environmental conditions. Besides, 100% output is controlled by in-line Anderon meters and all manufacturing data is collected by a centralized digital traceability system.
Nov
Nov
21
SKF is meeting the demands of the automotive industry with the two innovative products in one for electric cars
24
D’Artagnan Dredger Boasts 9-Year Wear Life of Cutterhead Shaft Bearings
SKF has launched a Motor Encoder Sensor Bearing Unit (SKF MESBU) for the electric and hybrid vehicle market. This significant development in sensor bearing technology is a first for the industry, integrating bearing and sensor technology in a single, compact unit. The SKF MESBU is specifically designed and manufactured to improve the operational performance and precision of electric and hybrid cars, including stop & start function based on starter-alternator devices. It also simplifies and reduces customer manufacturing costs significantly, because the sensor’s performance is totally independent of the customer’s assembly process.
Water lubricated Thordon Composite cutterhead shaft bearings have performed well for 9 years on one of the largest cutter suction dredgers in the world –Dredging, Environmental and Marine Engineering N.V. (DEME)’s D’Artagnan (28,200 kW total installed power). The vessel had a major dry docking at Drydocks World-Dubai in February 2014 where the shaft was removed, and bearings and shaft inspected. Originally built in 2005, the D’Artagnan self-propelled cutter suction dredger is involved in very heavy rock-breaking having a cutting power for operations in rock soils of 6000 kW.
Nov
24
Mature Industrial Bearings and Couplings Market To Grow as Users Look Beyond Price Rapid industrial development in high-growth regions such as Mexico, Indonesia, Nigeria, Turkey as well as Brazil, Russia, India and China is driving the industrial bearings and couplings market. The magnitude of the existing global installed base will strengthen the need for replacement and upgrades, adding to market demand. This push from developing economies is important as the market is technologically mature and seeing restricted growth in developed economies. This is particularly so in Europe and North America owing to financial instability and reduced capital expenditure across end-user industries. New analysis from Frost & Sullivan, Strategic Analysis of the Global Industrial
Page: 112
Bearings and Couplings Market, finds that the market earned revenues of $22.06 billion in 2013 and estimates this to reach $26.76 billion in 2018. The study covers key end-user segments including mining, metal working, material handling, energy, construction, and food and beverage. If you are interested in more information on this study, please send an e-mail to Julia Nikishkina, Corporate Communications, at julia.nikishkina@ frost.com. Bearing News • Issue 3
Nov
Nov
Nov
25
King Engine Bearings Launches New Website
27
NASA’s Curiosity Rover completed the first 687-day Martian year with GGB Bearings
29
New whitepaper from Festo looks at considerations and tips for bearings system designers
King Engine Bearings has just launched its new website featuring an updated visual design and easier navigation for visitors. Much of the technical information and content on the site has been updated and enhanced to reflect King’s current products and technical specifications. The new website’s format allows King to share the benefits of their newest bearing designs and materials. Visit the new website at www.kingbearings.com.
NASA’s Mars Curiosity Rover, which is fitted with metal-polymer bearings from GGB Bearing Technology, completed the first 687day Martian year of its mission. It landed on the red planet on August 5, 2012.
The majority of electro-mechanical axis utilise extruded aluminium profile in a range of sizes with a single guide rail and bearing arrangement driven by an electric motor through a belt or ball screw arrangement. There are physical limitations to the forces such a system can accurately and reliably guide. Festo has published a new whitepaper “Key considerations for designers looking at bearing systems with linear axes”. The white paper aims to help designers understand some alternative design arrangements to cope with higher load applications and identifies design
Dec
03
considerations observed during the development of a Festo high load, twin rail system and can be read on page XX in this issue of the BearingNEWS magazine.
NSK Exhibits at SEMICON Japan 2014
NSK Ltd. exhibits its products and technologies at SEMICON Japan 2014, at Tokyo Big Sight (Koto Ward, Tokyo) from Wednesday, December 3 to Friday, December 5. Driven by the immense demand for smartphone and automobile applications, the semiconductor market is expected to maintain robust growth. Semiconductors are being pushed to offer greater performance, multifunctionality, speed, and power savings, all while being smaller, lighter and lower in cost than
ever. In response to these high-level market needs, NSK has prepared the following semiconductor market-oriented products with superior features for its exhibit at SEMICON Japan 2014, based on the concept of Your Real Partner™ NSK’s Technology - Taking Your Business to the Next Stage.
Page: 113
What Happened in the
Bearing Industry Second Half of
Dec
04
2014
MTK+ expands the production range for big size ball bearings
MTK+ Bearing Factory have announced the expansion of the range for big size ball bearing manufacturing capabilities from 1500 mm OD up to 2900 mm OD, with her recently developed design and production unit.
order to meet the customized needs from customers; operational in the heavy industry.
The company announced earlier 2014 the expansion for the range of big size roller bearings from 1200 mm OD up to 3000 mm OD by expanding the organization in East-Asia with specialized engineers and further investments in production tools in order to accelerate growth and further strengthen the organization’s ability to capture strategic opportunities.
The recently produced ball bearing DGBB 2390 P6 shall operate in a pipe laying vessel active in the offshore energy industry and has the following specs:
MTK+ succeed with the diversification of the operational areas in the recent years and needed to achieve this further expansion of the production capabilities as a result of this strategic mission. The new design and production unit is enforcing the big size ball bearing production line of MTK+ with the latest advanced technical capabilities and tools in Page: 114
DGBB 2390 P6 • d = 2390 mm • D = 2690 mm • B = 120 mm • Weight = 975 Kg • Cor = 6200 Kn • Cr = 1300 Kn • Radial Clearance = 0.35 ~ 0.78 mm MTK+ Bearings are used in many applications in a wide range of industries such as general engineering, general machinery, crane industry, steel industry, offshore industry, food industry, agriculture and mining as well as in the replacement market. The full list of the application area’s and key industries as well as the production video of the big size bearing production line can be seen on the website www.mtk-bearings.com
Bearing News • Issue 3
Dec
04
RKB announces the opening of its new subsidiary in Romania The RKB Group expands its direct activities and global network by establishing a new wholly-owned subsidiary in Brasov, Romania, which operates under the name of RKB East Europe Srl. The opening of this new Logistics and Distribution Center is part of RKB’s strategy to provide East European customers with a single commercial and technical point of access and a full range of RKB bearings in stock, with focus on market specific items.
Dec
08
SKF announces new organizational structure SKF is merging its two Industrial business areas, Strategic Industries and Regional Sales and Service. The change will enable the benefits of the SKF asset life cycle to be applied to industrial customers in a more efficient manner, through a simplified organizational structure. It will also strengthen SKF’s focus on organic growth and profitability, supporting the Group’s financial targets. Effective 1 January 2015, SKF will operate through three business areas: Industrial Market, Automotive Market and Specialty Business.
Dec
09
Revolvo delivers bespoke bearing solution for Thames Water NHBB is pleased to announce the launch of a new, high temperature fabric liner technology, Vulkyn™ 650. This innovative fabric liner system for plain bushings and spherical bearings establishes a higher threshold for bearing performance within high temperature applications. Vulkyn™ 650 raises the maximum operating temperature of NHBB’s high temperature solutions by 25°F. As the suffix 650 suggests, the new liner solution provides reduced wear at 650°F of less than 0.006 in. after approximately 325,000 cycles. When tested at 570°F, the cycle count increases to 500,000 before liner wear reaches 0.006 in.
Dec
Dec
11
12
NHBB launches High Temperature Liner Technology for plain bushings and spherical bearings
NHBB is pleased to announce the launch of a new, high temperature fabric liner technology, Vulkyn™ 650. This innovative fabric liner system for plain bushings and spherical bearings establishes a higher threshold for bearing performance within high temperature applications.
operating temperature of NHBB’s high
Vulkyn™ 650 raises the maximum
wear reaches 0.006 in.
temperature solutions by 25°F. As the suffix 650 suggests, the new liner solution provides reduced wear at 650°F of less than 0.006 in. after approximately 325,000 cycles. When tested at 570°F, the cycle count increases to 500,000 before liner
NSK Holds Opening Ceremony at New Production Company in Mexico NSK announced that it held an opening ceremony to mark the successful start-up of its new production site in the state of Guanajuato, Mexico. The plant began operations in April 2014 and commenced mass production in July. The ceremony was attended by around 100 people from in and outside the company, including dignitaries from the Mexican government, NSK President Norio Otsuka, and Bernard Lindsay, senior vice president and head of all American operations. Page: 115
What Happened in the
Bearing Industry Second Half of
Dec
17
2014
Timken Solid-Block Bearing Units Cut Costs for Sawmill Operator
Timken spherical roller bearings with a solid block housing were developed for the harshest working conditions. They are capable of withstanding blows and falls and are available with optional steel covers (picture below) to protect against heavy soiling.
Sweden-based Derome Timber experiences sixfold increase in bearing service life By using Timken® spherical roller bearing solid-block housed units, the Swedish company Derome Timber AB increased cost efficiency and productivity in one of its sawmills on a long-term basis. The Timken assemblies achieved a service life in this application that was more than six times longer than that of a competitor’s product. Derome experienced challenges keeping the chain conveyor up and running at a sawmill in Veddige, on the west coast of Sweden. The conveyor system is part of equipment that rotates the logs for further processing. The heavy logs fall from a height of 50 cm onto the conveyor belt, causing severe shock loads upon impact. The climatic conditions (the machines are outdoors) combined with significant contamination create challenging conditions for the bearings. A competitor’s cast-iron bearing housings withstood these loads for three to four months. By then the housings were damaged or broken and dirt had penetrated into the interior, necessitating replacement of the bearings. Nomo Kullager AB, a preferred Swedish distributor of Timken products, recommended Timken spherical roller bearings with solid housings because they stand up to harsh conditions. The housing withstands blows and falls, and Page: 116
the bearings accommodate misalignments of up to ±1.5 degrees. Additionally, the ends of the feet on the housings are machined, which allows the keeper plates to fit tightly to the housing for one-time shaft alignment. The Timken housed units have now operated for more than two years in the Derome sawmill. “They have performed flawlessly and continue to look very good,” said Viktor Mattsson, a sales representative at Nomo in Gothenburg. Dan Bertilsson, sawmill maintenance manager, noted the significant savings. “For us, more than six times the service life means a considerable advantage. In this way we are able to reduce the repair and replacement time to a minimum and concentrate on other important things,” he said. The company is gradually substituting the Timken assemblies for the units previously in use. These housed units are designed for 40 to 180 mm shafts and are available in various types of housings, depending on the requirements. Users choose between labyrinth seals (Dupont Teflon®) and triple lip seals (nitrile or urethane). Milled pedestals, threaded puller bores, black oxide inner rings and numerous locking options for the shafts make it simple to install these high-performance units. In addition, optional steel covers protect the roller bearings from the heavy soiling that is typical in many industries, forestry among them.
Bearing News • Issue 3
22218CA/W33
The Search Engine for Bearing Distributors
www.bearingcloud.com Page: 118
Bearing News â&#x20AC;¢ Issue 3
ELIMINATION OF FALSE BRINELLING ROLLER ELEMENT BEARINGS
IN
False brinelling is a problem in assemblies which have low relative motion, high vibration, and a rolling element bearing. An example of this would be the bearings in the pitch control mechanism in wind turbines (Doll, G.), which may remain in a specific position for long periods of time.
IDENTIFY AND LABEL IT! The key to ensure that the right oil and grease gets into the right machine, is to allocate for each oil and grease itâ&#x20AC;&#x2122;s own distinct colour. Enluse can start you on the way to implement an effective Lubrication Reliability program by making your wall mounted colour-coded lube chart. We also supply a wide range of labels to identify any lube points in your entire plant.
10 coloured labelling convention wall chart
Dispensing Labels
Fill Point Labels
Coloured and Transparent Grease Guns
Coloured Grease Nipple Protectors
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KML Motion Industries Co.,Ltd. (Hong Kong) Address: Flat 5-7, 26th Floor, Saxon Tower, 7 Cheung Shun Street, Kowloon, Hong Kong, China Phone: 852-2425-1661 Fax: 852-2480-5866 E-mail: info@kml-bearing.com http://www.kml-bearing.com
Company profile Established in 1980, the KML pioneering and professionalism commitment to the bearing and transmission component markets. Through over thirty years of exploration in those markets, KML has built a high level of technical competence. Nowadays, KML has gained extensive customer recognition in the bearing and transmission market with its professional services. It has developed customers in 51 countries and regions. In particular, it has nurtured good reputation in America, Africa, etc. KML owns not only an outstanding technical service delivery team within China, but also powerful supply chain and integration capacity as well as wide product range that contributes to the one-stop, customized solution for customers. KML aims to provide you with tailor-made products of good quality and high cost-performance ratios. By now, our customers can buy the bearings, auto parts, truck and trailer parts from KML, majority of which are industry bearings, automotive bearings, belts, PTO-shaft and auto parts so on. These products can be produced according to the specific requirements of customers. In appreciation of KML's operational standard and quality management systems, KML was awarded ISO9001 and TS16949 certifications as far back as 1999. KML sticks to the customer-centric management principle and values customer satisfaction most. KML will continue to strive for excellence in expanding the market of Truck and Trailer Parts so as to deliver KML's outstanding products and services to customers in different parts of the world in a faster and convenient way!
A COMPARISON STUDY
FOR BEARING MANUFACTURING
CHINA INDIA VS
A COMPARISON STUDY
FOR BEARING MANUFACTURING
CHINA INDIA VS
Indian bearing manufacturing industry is relatively smaller as compared to the Chinese bearing industry with around 100 factories majorly consisting of small scale units having less than 40-50 employees. The industry is at the tipping point of growth given the increasing costs in China with which it has to compete. Primarily in India most of manufacturing units are working on semi-automatic machinery with flexible production lines which can cater to a wide variety of bearings in small to mid-size lots. Machinery, Market and Range With a majority of installed capacity for smaller size up to 300mm O.D, majority of the export business as well is in that range only. However few factories have the capacity to manufacturing up to 1 meter OD as well now. On the contrary the infrastructure for size range lower than 400mm is quite mature for special, taper and other roller bearings. Given the number of small scale units as well, India is positioned well to export special bearings is smaller quantity in comparison to China. Lot of factories are equipped with automatic production lines and are working mainly with OEM customers in automotive segment and gearbox manufacturers. Overall the quality level for taper roller bearing is higher than standard Asian factories as the lip area of taper roller bearings is also grinded. The production cost prices of some specific smaller roller bearings (ex. spherical roller bearings) are lower than those in China thanks to the automatisation and difference in the early stages of the production process.
Challenges and Future Currently Indian Bearings are exported almost all over the world under factory brand name and also in customersâ&#x20AC;&#x2122; private label. Indian manufacturers
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have great potential for growth if the industry receives little support from government for Capex, export benefits and subsidized loans. With cost of production and labor cost increase in China India has a great future in front of it. However Indian factories will have to continue to invest in equipment and machinery to support mass production. It is expected that the production in India will increase phenomenally over the next few years given the high availability of skilled labor and ability to communicate easily in English.
Meanwhile in China Numerous national players in the Chinese bearing industry are taking measures to strengthen their position in the domestic and international markets in order to increase further expansion abroad. Many manufacturers in China need to overcome a number of barriers. Not only do they have to deal with a tough price competition due to the large number of mainly smaller companies, they also realize the need for better production technology and automation. Research and development, for example to improve the quality of produced steel, lubrication applications, product specialization, are not easily accessible, except for the main companies of the industry.
Bearing News â&#x20AC;˘ Issue 3
The National Grinding Machine Tools Producers also put their views in the open. Their main market is the bearing industry itself and they follow the developments with close interest. The organization also agrees that structural changes are at hand. The markets for cheap, mass production bearings are saturated. Further expansion can only lie in developing medium and large size bearings of high quality. Whereas now the main target markets are situated in automotive and appliance, this would mean an expansion to machine tooling, alternative energy, mining and off-road industry, aerospace, etc., both on national and on international
playfields. Surely, this involves the loss of one of the main market advantages of the Chinese industry: low production costs and thus low prices. On top of that, the large number of small manufacturers keeps price competition at high levels. Increasing demand for higher quality means investments have to be made to produce higher quality bearings for specific applications. They realize that the average technology level has to be upgraded. However, many companies still lack the possibilities to invest in experience, skills, machinery and other resources.
Chinese bearing manufacturers are aiming for hightech, high-margin and high-precision bearings The need to keep and improve their position in the market as fastest growing sector, preceding India, draws on the support of the Chinese government. To stabilize the steel market, structural adjustments are called for. Price control, increased investment possibilities, availability of credit, all will have supporting effects. Many European manufacturers are already taking the opportunities to invest in Asia, in particular China and India. To ensure
this trend for the future, government policy measurements alone will not be enough. Main issue to resolve by the industry itself is that modern grinding machines of high quality are still too expensive to import for many smaller companies. Despite the fact that the Chinese bearing factories mastered the production of over 70 thousand types and sizes, their products are poorly represented in the market of high-tech,
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high-precision and high margin bearings. Chinese experts tend to believe that the national bearing industry will be able to take a significant position in the world market through the establishment of one of the most high-tech and capital-intensive industries in China. To reach this goal, several recommendations and suggestions have been made by The Association of Chinese Bearing Industry and the related industrial institutes and organizations. These have to trigger the transition into producing high-tech, highmargin and high-precision bearings, for which demand continues to grow worldwide.
Among these recommendations are: • The transition to multi-place machines for the forging of bearing rings with diameters ranging from 50 mm to 300 mm; • Use of induction heating for forging, which allows accurate temperature control and maintains a record of process parameters in real time; • Use of CNC machining centres for machining parts with diameters up to 300 mm in the production lines. • Ensure stability in the production process of the parts and rolling elements by using high precision machine tools;
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• Implement high-speed and co-grinding, for the grinding of bearing parts • For large amounts of processing, implement the use of auxiliary equipment for automatic line connection; depending on the type, size and requirements of the product; • To develop proper assembly lines for tapered roller bearings. • Actively develop ongoing assembly of bearings; • Facilitate the introduction of new generation, more efficient high-speed electric spindles, to assure environmentally friendly and low-loss lubrication in production. Chinese industry has a challenging task, on short term and on the longer term, if they want to keep their bearing export on competitive levels. To do this, not only the machinery will have to be updated to higher quality standards; research and development will need a boost, investments in know-how of production processes and closer integration with main target industries should at the same time be considered. If this will also lead to the disappearance of some of the smaller businesses, remains to be seen. One of the recommendations made by the Chinese Bearing Industry Association already was to have (smaller) companies work together in investments and
Bearing News • Issue 3
innovation, with the support of national politics, to achieve the realization of these goals. Follow-up and progress on these issues and others was discussed during a meeting between construction machinery and bearings industry. On behalf of the China Bearing Industry Association, Mr. Lu Gang had a speech about current development of bearing industry, transformation and upgrading, technology and quality progress, and how to meet the needs of users. He required enterprises to take a positive attitude to face the current situation, complete the process and quality improvement, make technical preparation, study the product trend of main equipment enterprises, research the technology trend of bearings and main equipments national and abroad, collect potential energy for the development of enterprises. Mr. Ban Yungang, senior engineer of FuWa Heavy Industry expressed the need to discuss specific technical questions with bearing enterprises in view of further technological improvement and development. Main points of interest were the efficiency of pulley bearings, installation tolerances, and the effects of temperature on the lubrication.
Maintaining position in the world wide bearing market. Fact is that competition stays hard, new technologies and know-how are expensive, and many companies are still overcoming the financial problems of a worldwide economical drop. Larger players will have a significant advantage in catching up with the needs of the moment. Still, realizing the problem is half the solution, and with the help of foreign investments, China remains a competitive player in the bearing market. They have now to realize the breakthrough into the 21st century by developing more specialized, application-specific, higher quality bearings. A challenge for sure. An NSK announcement at the end of 2012 of their plans to start to begin South Korean production of low-cost, high-precision bearings, could already be a sign that other important bearing manufacturers are starting to anticipate on these Chinese evolutions. With a production cost at 80% of that in Japan, they hope to challenge the growing competition
with bearings comparable in quality to Japanese production, made from lower priced steel. The company estimates that world-wide demand for automobile-transmission systems will increase at least 30% by 2019. Recent developments through 2014 also prove that several companies have indeed made the necessary planning and/or investments. We see new industries developing high-tech machinery to suit the bearing producers in their need to specialize. Factories come up with long term investment plans, production of spindle bearings is growing, and first signs of specialization start to appear. Apparently, China is not hesitating to put theory into good practice, in their effort to stay ahead of upcoming countries like India and others in the region.
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Serving worldwide industries for more than
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Spherical Roller Bearings â&#x20AC;˘ Taper Roller Bearings â&#x20AC;˘ Cylindrical Roller Bearings
Ian Knight Director of Enluse BV
Managing Machinery’s Silent Killer Friction costs industry a lot of money and the biggest reducer of friction is effective lubrication. However, most companies today do not manage their lubrication process effectively and hence do not get the benefits of reduced friction in their machines. WEAR IS one of the biggest fiction generators; simply put, when metal parts rub or touch, friction increases. Today wear in equipment is accepted, but not well understood. It is a killer of metal components, silent in its wearing process, until it reaches a detectable level and then it is too late as the damage has already been done. Effective lubrication management reduces wear and friction, and eliminates or reduces the Silent Killing process. This article is all about understanding how good or bad lubrication practices affect machine life and how to eliminate or manage the Silent Killer. The fact that bearings and machinery suffer from wear is well known and accepted in industry. However, the mechanism that causes the wear, how to manage it or how to prevent it, is not so common. Unless the operating lubricant is very clean and chemically sound, wear starts to occur the minute a component is put into service. The development of the wear is dependent on the hardness and size of the foreign particles, the load on the application and the effectiveness of the selected lubricant. The types of wear we are referring to are abrasive Page: 134
wear and adhesive wear. Abrasive wear occurs when there are particles in the lubricant that are greater in size than the lubrication film thickness itself. Adhesive wear occurs if the lubricant does not provide sufficient separation of the mating surfaces causing metal to metal contact. The silent killing phase is the period of time it takes for the wear process to reach the point where the damage can bedetected by traditional means. Examples of damage detection include an increase in overall vibration levels, seal leakages and heat generation. As we have discussed, the problem we face is that when we are able to detect this level of wear, the damage has already been done and cannot be reversed. All we can do at this stage is manage further deterioration of the worn part and prevent catastrophic failure. What most people do not understand is that the lubrication film thickness is very small – only a few microns; as a result it doesn’t take large contaminants to start the wear process. Bearing News • Issue 3
Managing the Killing Process The bad news is that the wear responsible for the Silent Killing process starts from day one of operation of a new component or piece of equipment. The good news is that it can be prevented and the POINT OF NO RETURN can be significantly extended in time. It can almost be eliminated – meaning a significant increase in component life or MTTF (mean time to failure). This all naturally relates to an increase in equipment up-time, a reduction in maintenance needs and costs, and consequently to an overall increase in operating performance and results. The difficult part in achieving an increase in operating performance is the prevention of the silent killing phase. This can be summed up with just one statement – one need to manage the lubrication processes more effectively. In other words implement a Lubrication Reliability strategy.
Lubrication Management The term Lubrication Reliability describes a process that ensures the lubrication works in a reliable manner. If it does not, an effective separating lubrication film thickness is not achieved and the process of wear starts to occur. There are many factors that can affect an effective lubrication process, and therefore prevent the creation of a good separating lube film thickness. These can be addressed by applying the 6 Lubrication Rights (6R’s) to each and every lubrication point. If any of the following questions are not answered positively, then we stand a good chance of the Silent Killing process kicking into gear. The 6 Lubrication rights are: • The Right Lube • At the Right Time • In the Right Quantity • In the Right Place • In the Right Way • In the Right Condition
Reducing the Killing Process Cleanliness control is the most critical component of an effective Lubrication Management Strategy, as contaminated oil is the biggest cause for machine
andactivity. The best assessment on how effective your lube management system is component wear. Without this, the Silent Killing process goes into effect. This is managed by effective filtration processes, driven by oil analysis. However, many organizations have not recognized the need to invest in having clean oil operating inside their machines or equipment. Research conducted by Dr. MacPhearson from Westland Helicopters showed the relationship between filter ratings and clean oil to millions of cycles, to fatigue failure of a bearing. What this says is that the cleaner the oil the longer the bearing life. If you have a fine filter rating of 3μ, you can maximise bearing life. See figure 1. The most common measurement used to assess the contamination level in oil is compliance to ISO 4406 cleanliness standards. The achievement of a lower ISO 4406 cleanliness code, from 22/18/13 to 16/12/8, can be regarded as a best practice level for hydraulic systems. This will significantly increase component or machine life. Note on figure 2 the mean time between failure increases, due to the lower ISO 4406 codes.
Controlling the Process Companies that understand the benefits to be gained from having an effective lubrication process in place are consistently managing the process. This generally entails dedicated and well-trained staff, consistent adherence to the 6 lubrication rights and the use of a dedicated lubrication database. Many companies use their existing CMMS system to manage their Lubrication activities. Our experience is that most of these systems do not go into enough detail to effectively manage the would be to ask the following six lubrication right questions for the every lube point. If we can answer yes we have a best practice situation. If not then rest assured the Silent Killing process will be in play. From our years of experience at lubrication plant practices, we have determined the base standards that need to be in place in order to achieve best practice levels. These can be broken down to 4 key areas, covering; 1 - the strategic part, 2 - the cleanliness control and contamination part, 3 - the database management and reporting section, 4 -
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Figure 1. Clean oil relationship to bearing life.
Figure 2. Lower ISO 4406 code relates to lower maintenance costs.
lubrication knowledge and its applications.
filling mechanisms to suit all fill points, OilSafe is
Also we endeavour to determine how advanced the complete lubrication strategy is on a maturity scale. We generally see that the implementation of a best practice standard goes through 4 evolutionary
undoubtedly the global best practice in lubrication
steps – basic requirement, lubrication processes, proactive lubrication management and the overall plant asset efficiency culture.
need to breatheand if they do not have breathers
Base examples of each level are shown in the following graphic along with some important fundamentals for each component and maturity level.
an excellent tool for not only stopping dust and dirt
The Lube Room
today, in our opinion, is the Air Sentry Guardian
Without exception, all plants that are at best practice levels, manage the oils correctly in their lube room or lube storage area. The lube room is the base standard of ensuring that only clean and chemically sound lubes are added to the equipment. A best practice storage area standard clearly identifies the different lubes, filters the oil to a clean standard and protects the oil from moisture, dust or dirt, whilst controlling temperature variations. The best practice standard is the Oil Safe Bulk storage system. See Figure 3.
Dispensing System The easiest standard to put into place is the OilSafe dispensing system. With its 10 different colours and drum sizes that match differing dispensing needs, along with many different and fully sealed Page: 136
dispensing. The biggest sources of contamination for operating oil are airborne dust, dirt and water. Oil reservoirs that condition the air on the way in, then the oil easily gets contaminated. Desiccant breathers are particles from entering the oil, but they also absorb moisture from the air. The best practice desiccant breather on the market breather. The breather not only filters for dust, dirt and absorbing moisture, it also has a unique check valve technology ensuring that any exhaust air does not go through the breather thereby further contaminating the water absorbing gel. It simply makes the breather last much longer – it is the best value for money on the market today. A best practice tool for training the staff on this subject is the Reliability Institute’s Bearing Failure and Causes on line training programme. This course can be found on the Reliability Institute Web Site. www.reliabilityinstitute.com. The company Enluse BV specializes in helping industry to achieve best practice standards in lubrication reliability, which is the process to eliminate the Silent Killing process of the bearings. We can be contacted via the following homepage: www.enluse.com. Bearing News • Issue 3
Are failures like these happening in your plant? Lubrication Reliability By implementing a lubrication reliability strategy in your plant will have the effect of eliminating bearing failures and reducing equipment wear - with the effect of improving your equipment reliability. Enluse BV has the knowledge and the product lines to help you implement a lubrication reliability strategy in your plant.
Identify and Label it!
Statistics reveal that more than 60% of bearing damage is lubrication related!
Managing Your Strategy
Store it, clean it, keep it clean!
Air Sentry Breathers
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Full Line of High Precision Rotary Stroke Bearings from Mahr Federal Provide high guiding accuracy for both linear and rotary movements with zero backlash and low friction for stick-slip-free movement. A full line of Rotary Stroke Bearings is now available from Mahr Federal. Suitable for a wide range of applications where linear, rotary, and combined movements are required, MarMotion high precision linear or Rotary Stroke Bearings are frequently specified for high precision applications such as machine tool spindles and pick-andplace assembly robots used in semi-conductor manufacture. MarMotion bearings have even been used on the Hubble telescope. Originally developed by Mahr in order to increase the measuring accuracy and certainty of its dimensional metrology products, MarMotion high-precision rotary stroke bearings are used in measurement transducers, positioning units, centering and tilting tables, and in other modules that have an influence on the measuring result. MarMotion high-precision rotary stroke bearings exhibit virtually no backlash, stick slip or wear,
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and their motion is exceptionally smooth and reproducible. Other popular applications for MarMotion Rotary Stroke Bearings include uses such as components in packaging machines in a wide range of industries, in automatic assembly units, textile machines, and high-quality special-purpose machines. MarMotion bearings are used in optical engineering to enable stick-slip-free movement of lenses, mirrors and diaphragms, and are suited for both large and heavy optical elements as well as for miniature design in small objectives. In precision engineering applications where miniaturization requires compact instruments, MarMotion MINI series rotary stroke bearings provide stick-slip freedom, easy movement and maintenance-free operation. Small ball diameters reduce installation space, and â&#x20AC;&#x2DC;Minisâ&#x20AC;&#x2122; come paired without play for components including small
Bearing News â&#x20AC;˘ Issue 3
control elements for placer heads and laser welding technology, as well as blade holders, jigs or fixtures. MarMotion high-precision rotary stroke bearings assure high guiding accuracy for both linear and rotary movements. The size and form accuracy (roundness and cylindricity) of the micro-finished running faces of shafts and bushings is less than 1/3 ISO standards; and only grade 5, sorting class P0 steel balls (DIN 5401 or ISO 3290) are used. Factory- preloaded balls and a low coefficient of friction virtually eliminate backlash and ensure smooth operation. The extensive range of MarMotion high-precision rotary stroke bearings offers appropriate solutions for many different applications. Options include various thread combinations of guide shafts; closed or open guide bushes with or without stop rings; sealing rings or wipers; and plastic or brass ball cages with ceramic or stainless steel balls. Mahr
can also manufacture special designs for particular applications and requirements, or use alternative materials. Mahr Federal Inc., a member of the Mahr Group, has been providing dimensional measurement solutions to fit customer application needs for over 150 years. The company manufactures and markets a wide variety of dimensional metrology equipment, from simple and easyto-use handheld gages to technically advanced measurement systems for form, contour, surface finish and length. Mahr Federal is also well known as a producer of custom-designed gages and a provider of calibration and contract measurement services. Mahr Federalâ&#x20AC;&#x2122;s calibration laboratories are accredited to ISO/IEC 17025:2005 NVLAP Lab Code 200605-0 (see our Scope of Accreditation for accredited calibration processes). For more information visit www.mahr.com
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Bearing News â&#x20AC;¢ Issue 3
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Every manufacturer would prefer to choose the proper production technology on the clear cost-reduction basis. But often it can be difficult. In contrast to the well-known mass production, modern bearing manufacturing is very flexible and complicated for economical analysis. The manufacturing costs become very variable if hundreds of differentprecision parts are produced in small batches. And precision OD grinding of the rings is especially volatile part of the process. The grinding cycle
time and machine setup time highly depend on the stiffness of the ring and roundness tolerance assigned. The other important factor is the portion of the rejected rings (including the ones used to prove machine setup). All these matters make the detailed cost analysis too labor-intensive and expensive itself. To make the situation easier we offer to compare the OD grinding costs calculated for the typical case. The found ratios can be extended to other cases with the use of according scaling factors.
Costs of precision OD grinding depending on the technology and specific stiffness of the ring.
The above chart shows the costs per one ring for various OD grinding techniques depending on specific stiffness of the ring (stiffness per grinding width) and in correlation to the dimension series (OD/ID ratio). The cost analysis takes account of grinding cycle time, setup time, part loading/unloading time. The costs found for the following conditions: the production lot of 200 rings with the outer diameters 180mm and roundness tolerance 0.0025mm. Of course, the absolute figures vary for different companies
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and countries. But the ratios remain practically the same for 100mm<OD<400mm. The wide analysis confirms the centerless grinder is effective for the large production lots (>1000pcs.), if the rings are stiff enough. Clamping on the magnetic chuck is acceptable for the small lots (<50pcs.).
RON-Centric (RON-Centric-T) is the most costeffective solution for the production lots from 50 to 1000pcs.
Bearing News â&#x20AC;˘ Issue 3
TORQUE MONITORING The Secret Weapon Torque monitoring is an ever-increasing trend, present in industries like cement, marine and power. It provides users with a deeper understanding of the operational demands of their machines when it is difficult to diagnose a problem through standard vibration analysis. This way, users can make the necessary corrections to ensure smoother operation and avoid unexpected failures.
Machines are tools that are specially designed to perform specific tasks. In order to do that, they convert energy into work. Let us look at a bucket elevator for example. The energy flows through each of the components of the machine train, from the motor through the gearbox to the bucket elevator. The motor turns electrical energy into mechanical energy, the shaft of the motor and the input shaft of the gearbox are linked together through a coupling, and the output shaft of the gearbox is connected to the bucket elevatorâ&#x20AC;&#x2122;s driving shaft. Like any ordinary chain, a
Figure 2. Broken teeth on the gearbox of a bucket elevator
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machine train is only as strong as its weakest link. Depending on the operational demands of the bucket elevator, which we can see as the load, the amount of power delivered by the motor will vary. The actual force making every shaft rotate is called torque, and it is directly proportional to the power. This means that when we want to maintain a certain operating speed on our process, and the load increases, the motor must deliver more power, and that is achieved by increasing the torque. Taking a closer look at the machine elements involved into this transmission chain, such as all the gear teeth of the gearbox, the coupling, the different shafts, we can find a great number of parts that can break, if they are not able to resist the torsion due to the applied torque. Breakage in any of these elements can be attributed to any number of reasons, ranging from design flaws, bad material quality, wrong selection of the machine components, incorrect operation of the machine, or extreme operating conditions that were not catered for in the machineâ&#x20AC;&#x2122;s original design, just to name a few. Bearing News â&#x20AC;˘ Issue 3
Figure 1. Typical components needed for measuring torque
What is condition monitoring?
Figure 4. Static torque readings, stored every second
Figure 6. Dynamic torque during operation at full load
Figure 5. Dynamic torque measurement during machine startup
Figure 7. Frequency spectrum from the dynamic torque signal
Condition monitoring is one of the key aspects of predictive and proactive maintenance strategies. By analogy to a doctor and his patient, the maintenance specialist is in charge of monitoring the health of his machines. However, instead of measuring blood pressure, pulse, respiratory rate, etc., the maintenance specialist measures vibration,
Figure 3a. Strain gauge on the shaft
Figure 3b. Mounting place on the shaft
torque, oil quality and temperature, among others. By doing this, he is able to quickly detect changes in the machineâ&#x20AC;&#x2122;s condition and to take the necessary steps in order to get ahead of any potential failure, keeping the machine and the production running smoothly. The benefits of a properly implemented condition monitoring program are numerous: fewer unplanned shutdowns, lower maintenance costs, fewer spare parts needed in stock, increased productivity and uptime, and an extended machinery lifetime.
How to measure torque Strain gauges connected as a Wheatstone bridge and protected against humidity and contamination, are applied to the twisting shaft (Figure 1). As the
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gauges are deformed due to the stresses generated on the shaft, its electrical resistance changes proportionally. A voltage signal is forced to pass through the strain gauges in order to measure this electrical resistance. The signal is amplified, transmitted via a rotating antenna, and then picked up by a stationary receiving antenna. Lastly, it flows to an evaluation unit where it is rectified and measured just as any other process parameter signal. Knowing how much the surface of the shaft has elastically deformed, the dimensions of the shaft, and its modulus of rigidity (a physical property of the shaft’s material), it is possible to determine the torque that the shaft is subject to.
Torque measurement on a bucket elevator The Service and Diagnostic Centre of PRÜFTECHNIK Condition Monitoring performed torque measurements on a bucket elevator in a cement factory. This service was ordered by the customer because of damage and breaking of some gear teeth inside the gearbox (Figure 2). The customer had reported that the gearbox had been functioning for several years without problems. However, in the last two years, there were two separate incidents only seven months apart. The strain gauges and the necessary equipment were installed on the output shaft of the gearbox (Figure 3). Alongside the torque measurement components, accelerometers were also mounted at key measurement points. In order to correlate the torque and the vibration readings, VIBGUARD, a multichannel condition monitoring system developed by PRÜFTECHNIK was used to allow the synchronous measurement of all signals. The machine was monitored while on standard production overnight, on the next day in idle state (no load) and during start-up. Initial static torque readings showed slight vibrations during normal operation (Figure 4), however they are not uncommon in such type of machines, and they do not surpass the nominal torque of the output shaft of the gearbox. The next step was to measure the load during the startup of the machine. Since this process is short in time and highly variable, the dynamic torque must be measured, which is the AC component of the signal. In order to do this, a high-resolution Page: 148
signal was recorded. Figure 5 shows that although the highest peak is just above the 29.400 Nm nominal torque, a negative torque appears, which is undesirable in any gearbox, and reflects an unusual behavior of the fluid coupling. Lastly, dynamic torque was also measured while on full load operation. Analyzing the time signal, oscillations could be clearly identified, but with additional superimposed higher amplitude shocks, which are separated roughly 45 seconds from each other. From the original signal, an FFT analysis was made in order to find the frequencies of the torsional vibrations (Figures 6 and 7). In the frequency spectrum, a dominant peak was seen at 3,5 Hz, which is the passing frequency of the buckets. It was recommended to the customer to reduce the amount of oil in the fluid coupling, or to reduce the tension in the bucket belt, in order to eliminate the negative torques. In the long term, buckets should be reduced in weight, or the gearbox should be replaced for a stronger one.
Conclusion When it comes to protecting your assets, combining torque measurements with condition and process monitoring offers a unique advantage. By closely analyzing torque, you can directly assess the operational requirements of a machine, detect incorrect operation and even design flaws. Measuring torque can be performed as a service, carried out temporarily with a portable data collector, or installed permanently, whereby the torque signal will be continuously analyzed by an online condition monitoring system. No matter the age of the machine, torque measurement can be implemented at any time. For production critical machines, it is highly recommended to implement an online vibration and torque monitoring system. In most cases, the repair costs of an unexpected machine breakdown and the total value of the production loss can easily outweigh the initial investment of the implementation of the said system.
Bearing News • Issue 3
STORE IT, CLEAN IT, KEEP IT CLEAN! New oil is not necessarily clean. With our modular bulk system your oil can be both stored and cleaned to a the standard you require All systems come in the standard 10 OilSafe colours and there are many storage volumes and combinations available to meet all needs. The OilSafe dispensing system is the ideal partner of the Bulk System to achieve a Best Practice standard in Lubrication Reliability.
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An Instant Lube room
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AVAILABLE FROM OUR SELECTED DEALERS Bearing News â&#x20AC;¢ Issue 3