Fastener Engineering December 2023

December 2023 www.fastenerengineering.com

2023 How do vdc and non-vdc adhesives compare?

keeping a

low profile:

How micro screws support lighter, more aerodynamic designs page 30

cover – fastener hb december 2023 v3 final.indd 1

page 26

How does “direct-pass” ultrasonic metal welding support evs? page 34

what are the different styles of retaining rings? page 37

12/7/23 2:21 PM

adhesives Did you know that 100% solid epoxies typically contain no Volatile organic compounds (VOCs)? They’re ideal for applications in enclosed spaces and those with large bonding or coating areas.

How do

VOC and non-VOC adhesives compare?

Article courtesy of Master Bond

Volatile

organic compounds (VOCs) are compounds that have high vapor pressure and low water solubility. Many VOCs are human-made chemicals used and produced in the manufacturing of paints, pharmaceuticals, and refrigerants.

VOCs are typically industrial solvents or by-products produced by chlorination in water treatment, such as chloroform. They’re common ground-water contaminants and often components of petroleumbased products, hydraulic fluids, paint thinners, and cleaning agents. They’re also emitted by an array of products numbering in the thousands.

A few examples of products that contain VOCs include paints and lacquers, industrial adhesives, paint strippers, cleaning supplies, pesticides, building materials and furnishings,

26

December 2023

adhesives – fastener hb december 2023 v3 final.indd 26

office equipment (such as copiers and printers), correction fluids and carbonless copy paper, graphics materials, permanent markers, and photographic solutions.

Concentrations of many VOCs are consistently higher indoors (up to 10 times higher) than outdoors.

Health effects of VOCs The extent and nature of the health effects of VOCs will depend on several factors, including the level of exposure and the duration and frequency of exposure.

Some of the symptoms that can occur after exposure include: • Eye and respiratory tract irritation • Headache • Nausea and dizziness • Visual disorders • Memory impairment www.fastenerengineering.com

Some VOCs can also cause cancer in animals (based on toxicological studies).

VOC regulations Clean Air Act standards, Environmental Protection Agency (EPA) VOC standards, and regulations pertaining to the use of solvents in various industries are as follows.

• National Emission Standards for Hazardous Air Pollutants (NESHAP) • New Source Performance Standards (NSPS) • Control Techniques Guidelines (CTG) • Alternative Control Techniques (ACT) • National Volatile Organic Compound Emission Standards – 183(e) VOC Rule

DESIGN WORLD

12/11/23 9:51 AM

DW Fastener Eng K-Blog_SS_Radar_12-23p.indd 1 5 keystone – HdBk fastener engineering december 2023.indd

11/1/23 10:18 AM 12/11/23 10:13 AM

Pressure Sensitive

Polymer Film

adhesives

Adhesive Lamination

Process Benefits • Short run laminations • Adhesive versatility • Fast turnaround • Uniform Adhesive Coating • Liner Application Types of Products • PTFE made with Teflon® Fluoropolymers • Kapton® Polyimide • PEEK • Nylon® 6/6 • ULTEM® PEI • Mylar® • PVDF • UHMW

The EPA recommends that states adopt requirements consistent with the presumptive Reasonably Available Control Technology or RACT (groundlevel VOC). These measures are only a recommendation, and states may develop their own RACT requirements on a case-by-case basis, based on the economic and technical circumstances of individual sources.

Currently, no federal laws or regulations preclude states from requiring more stringent controls than those recommended as RACT. Some states might require additional control to meet the national ambient air quality standards (NAAQS) for ozone in some areas.

VOCs are an extremely important consideration in industries such as aerospace, medical, electronics, oil &

chemical processing, and industrial OEMs. The key to ensuring that VOCs are mitigated is to select compounds that contain no solvents or high levels of VOCs. This will limit the VOC from the start and reduce the outgassing of VOCs over time at a device level.

Reformulation to lower VOC content would be beneficial from health and safety aspects and require less VOC control measure equipment.

Epoxies that are 100% solid typically contain zero volatile organic compounds, making them ideal for applications in enclosed spaces and those with extensive bonding or coating areas.

Learn more at masterbond.com

Resources Guidelines from the Environmental Protection Agency (EPA):

Adhesive Options Acrylic High Bond Acrylic Silicone

•

Volatile Organic Compounds' Impact on Indoor Air Quality tinyurl.com/AirQualityVOCs

•

“Control of Volatile Organic Compound Emissions from Coating Operations at Aerospace Manufacturing and Rework Operations” tinyurl.com/ControlVOCs

Additional Services Custom Die Cutting Roll Slitting Rewinding Automated Sheeting

800-461-4161 www.cshyde.com 28

adhesives – fastener hb december 2023 v3 final.indd 28

December 2023

www.fastenerengineering.com

DESIGN WORLD

12/11/23 9:51 AM

ming tai – fastener engineering december 2023 | PU 12-22.indd 1

12/11/23 10:14 AM

screws

what are

low-profile screws?

By Hiroki Goto, Engineering Manager | NBK America LLC

Low-profile

screws are made with a lower head height than typical screws. These fasteners are designed with a minimal or flush head that sits close to the surface of the material being fastened — providing low visibility but a secure attachment. These components are also referred to as slim head, micro, or lowprofile cap screws.

The smaller size and thinner (lower) heads mean these fasteners are typically used for smaller devices and equipment or where clearance is limited. For example, they’re ideal for applications with limited space for bolt mounting.

With minimal protrusion after mounting, they can also reduce concerns about interference.

Low-profile screws solve specific problems, like fastening to thin sheets where counterboring is impossible. In

such cases, regular screws require deep counterbored holes, calling for larger surface material. Low-profile screws completely eliminate the need for counterboring.

Additionally, these screws are commonly used in applications where aesthetics matter, and the appearance of the fastened surface is important. By design, low-profile screws offer a sleek, discreet finish.

•

• Typical features • Head design: Low-profile screws usually have a flat or slightly countersunk head design. The head is flush with the surface or slightly recessed, ensuring minimal protrusion.

• Reduced height and weight: Compared to conventional screws, those with lower profiles often have a shorter overall length, allowing them to remain close-to flush with a surface without protruding. The thin head means these fasteners are

lighter than ordinary screws, making them ideal for many lightweight applications.

Thread size: Sometimes, lowprofile screws also have a reduced thread height, where the threads are shorter to prevent them from protruding out the other side of the material. This is helpful in the context of fastening materials with limited thickness.

Variation: Much like typical screws, low-profile fasteners are available in various sizes, materials, and drive types, providing flexibility for different applications and a range of industries.

Applications Given their minimal design, lowprofile screws are widely used in the electronics industry for securing components, circuit boards, and electronic enclosures. Their flush or recessed heads minimize interference.

They’re also used in drones, automation

Drones are designed to minimize air resistance and achieve efficient flight. Using low-profile screws in their assembly helps maintain a smooth, lightweight surface, reducing protrusions that could disrupt airflow around the drone.

30

December 2023

screws – fastener hb december 2023 v4 final.indd 30

www.fastenerengineering.com

DESIGN WORLD

12/11/23 9:55 AM

DESIGNERS & MANUFACTURERS OF NON-THREADED FASTENING SOLUTIONS

SLIC PINS™

PINS / COTTERS

U.S. Patent No. 6,872,039 & 7,147,420

• Proven and Popular • Pin and Cotter All-In-One • Speeds Assembly Time • Strong, Safe, Fast

CABLES, LANYARDS & TETHERS QUICK-RELEASE PINS

AND MORE...

• Stock and Custom • Free Samples • Fastener Training Sessions (Digital or On-Site) • Free Engineering Assistance • ISO 9001:2015

Nylon Injection Molded!

An Inexpensive Light-Duty Tether

(800) 222-2231 mail@pivotpins.com pivotpins.com Pivot Point 12-22.indd 15

761 Industrial Lane P.O. Box 488 Hustisford, WI 53034

12/11/23 10:15 AM

screws robots, and certain automotive components (securing interior trims, panels, and consoles) because these fasteners are lightweight and unobtrusive. They support unrestricted energy flow and can result in cost savings.

Thanks to their aesthetic nature, these fasteners are also frequently used in cabinetry, woodworking, and the furniture industry to secure hardware. They provide a clean and discreet appearance while maintaining structural integrity.

Low-profile fasteners are also used in critical applications, such as medical devices and other applications where space and weight are critical factors.

Choose wisely There are several advantages to using low-profile screws, given their smooth, lightweight characteristics. However, it’s important to do your due diligence and choose the fastener that ideally fits your application.

Although these screws offer secure and reliable fastening in most applications, their thin head is not always an advantage. It can result in lower strength with different widths than conventional hex socket head cap screws. Also, when using both hex socket head cap screws and low-profile screws, different tools may be required, causing extra challenges. Nevertheless, low-profile screws offer a streamlined, secure option for many applications.

Low-profile screws are ideal for use to prevent interference when opening and closing equipment doors (top image) or for equipment that does not allow for deep countersunk holes.

The advantages of low-profile fasteners…

•

•

• •

Minimalism – a thinner head means these screws are smaller and lighter than typical screws, making them ideal for space-saving designs, smaller devices, and lighter-weight equipment Safety – low-profile screws reduce the risk of catching, snagging, or even injuries that can result from exposed or protruding screw heads Aesthetics – a clean, smooth appearance Maintenance – for the most part, smaller, low-profile fasteners mean easier maintenance

Low-profile fasteners ensure minimal protrusion after mounting, reducing the risk of snagging, catching, or interference.

32

screws – fastener hb december 2023 v4 final.indd 32

December 2023

DESIGN WORLD

12/11/23 9:55 AM

able – fastener engineering december 2023.indd 1

12/11/23 10:15 AM

welding

Alex Yeung, Global Product Manager, Branson Welding and Assembly at Emerson

how does “direct-pass”

ultrasonic metal welding support evs?

Manufacturers

of electric vehicles (EVs) continue to look for ways to improve battery technologies despite a substantial recent reduction in the cost per kilowatt-hour for lithium-ion batteries. Many aim to significantly increase energy densities to provide greater driving distance between charges, faster charging times, and a reduced risk of overheating. This will also enable the use of nonflammable electrolytes. Increasing the energy density of EV batteries requires adding substantially more layers of the anode/ cathode/electrolyte thin foil materials used by the industry. These thin foil layers give EV batteries the ability to charge, store, discharge, and release electrons that produce the electric current that powers the vehicles.

In current EV batteries, graphitecoated copper is the most widely used thin foil material, welded to a single, heavier, nickel, or nickel-coated copper tab. Cathode foils are made from aluminum and are welded to a single, heavier-gauge aluminum tab. These foilto-tab weld assemblies let the current charge and discharge through the external casing of individual battery cells.

By adding layers of these thin foils — while staying within the physical parameters of existing battery designs

34

December 2023

welding – fastener hb december 2023 v9 final.indd 34

(for example, 18650/20700 cells or flat prismatic cells) — these more powerful batteries have increased surface area to collect and transport electrons, increasing energy density and battery capacity.

However, increasing energy density by this method can present problems.

The ultrasonic metal welding technology typically used for the foil-to-tab bonding process can only produce reliable assemblies using a maximum of 40 to 50 foil layers. Adding foil layers requires higher welding amplitude to bond the layers.

When the number of foil layers (ranging in thickness between five and eight microns) approaches 60 or more, the higher amplitude needed to bond them results in increased particulates and damage to the metal foil — such

as wrinkling, cracking, and tearing.

Such damage, which increases the risk of short circuits and threatens battery quality by reducing current capacity, can be detected by monitoring weld quality data/limits, performing strength tests, and conducting visual inspections.

Conventional ultrasonic welders could not effectively make the foilto-tab welds. They used a horizontal oscillation technique that delivered weld energy through a cantilever-type actuator, which extended outward before adding clamp force. When more foil layers were added, the actuator arm created additional vibration that compromised clamp stability and allowed foil layers to wobble and shift.

Unfortunately, increasing amplitude to compensate made the excessive vibration worse. Clearly, a new metal

Ultrasonic welds provide the most proven and reliable solution for interconnecting the thin copper foils and tabs that are typically used as anode current collectors, as well as the aluminum foils and tabs used in many cathode current collector structures.

Photo courtesy of Emerson

www.fastenerengineering.com

DESIGN WORLD

12/11/23 10:01 AM

FOR WHATEVER YOU’RE MAKING,

WE’LL DO OUR PART.

PRECISION STAMPINGS, WASHERS, SPACERS & SHIMS. For over 100 years, nearly every industry across the globe has trusted Boker’s to provide quality components, world-class service and fast delivery.

REQUEST YOUR FREE 2024

Catalog & Calendar (800) -WASHERS

bokers – fastener engineering december 2023.indd 5

bokers.com

12/11/23 10:16 AM

welding

welding technology was needed to deliver reliable, foil-to-tab welds on these thicker stacks of metal foils, and engineers have delivered.

A new form of ultrasonic welding A new “direct press” ultrasonic metal welder makes it feasible to weld thicker foil layers. It has a vertical actuator that applies more clamp force on the welded parts, holding them with greater stability.

Several factors contributed to the welder’s success.

The motion of the vertical actuator could be more carefully controlled, undesirable actuator stress and vibration could be eliminated, and the tooling “grip” on the parts was improved.

The result is a weld process that’s much gentler and provides more consistent, higher quality due to the lower amplitude required. The new method has been validated, consistently welding up to 80 or even 100 thin foil layers without damaging the fragile foils.

In trials with manufacturers, this new directpress welding technology has proved its ability to produce high-quality spot welds on 100 layers of 10 micrometers (µm) copper foil to a 0.5 millimeter (mm) copper plate and 86 layers of 10 µm copper foil to a 0.2 mm nickel-coated copper tab.

Using the new direct-press technology, battery manufacturers can produce more reliable, longerrange, more energy-dense batteries. These batteries, coupled with improved charging systems and nonflammable or even solid electrolytes, should result in electric vehicles with greater driving range and operational safety.

The Branson GMX-20DP “Direct Press” Ultrasonic Metal Welder from Emerson. The reliability of the welds produced by this method have been validated by laboratory and customer tests.

36

welding – fastener hb december 2023 v9 final.indd 36

December 2023

DESIGN WORLD

12/11/23 10:01 AM

rings

what are the different styles of

retaining rings?

Retaining

rings — unassuming but critical components in engineering and mechanics — come in various forms, each with unique characteristics and advantages. They secure assemblies onto a shaft or in a housing or bore.

Selecting the ideal style and assembly method is crucial. This guide sheds light on their different features and benefits.

Tapered section rings: Axial, also known as circlips, tapered section retaining rings feature a tapered design where the radial width of the crosssection decreases from opposite the gap down toward the lugs. This profile allows the ring greater radial flex to tightly grip the bottom of the groove, equipping it to withstand significant thrust loads.

Functioning as a lightweight alternative to conventional fasteners (such as screws, nuts, and bolts), these rings can handle substantial forces in a properly designed application.

Alternative tapered section rings can alleviate vibration,

movement, or noise in applications.

Bowed and beveled retaining rings use the spring properties of the ring to effectively counteract the impact of accumulated tolerances, assembly wear, and endplay.

Most axial assembled retaining rings feature lugs and lug holes, offering ease of installation and removal.

Simple automation allows for the ring to be expanded over a mandrel for positioning in the groove and is recommended for high volumes or when repeatability of installation is important.

Tapered section rings: Radial retaining rings combine function with simplicity, offering a choice of configurations.

They’re engineered for applications requiring low thrust loads and when radial installation is imperative due to interference from other components.

Radially

Article courtesy of Rotor Clip

installed rings are available in various styles, including e-rings, c-rings, and poodle rings, in configurations to suit several assembly requirements. One advantage is these rings are often a cost-effective alternative to their axial counterpart.

Since radial rings do not need to flex as much as an axial ring during installation, they provide greater contact with a retained part when designing smaller assemblies.

Similar to axial rings, there are options for bowed configurations that effectively counteract vibration and shock impact. The spring-like nature of the rings enables them to absorb movement, reducing the transmission of forces to the rest of the assembly.

Constant section or snap rings, commonly known as snap rings, exhibit a consistent width (or radial wall) along their entire circumference — typically establishing three points of contact within the groove.

This uniformity guarantees a steady, unvarying interface that serves as a shoulder, firmly anchoring an assembly

Tapered section retaining rings

DESIGN WORLD

rings – fastener hb december 2023 v7 final.indd 37

www.fastenerengineering.com

December 2023

37

12/11/23 10:04 AM

rings in position. Thanks to their lug-free design, these rings excel in scenarios with restricted clearances or confined spaces.

Snap rings are frequently chosen for their reliable cross-section, bolstering their capacity to effectively withstand impact loads. This makes them ideal in applications where strength and durability are paramount.

Self-locking or push-on rings offer a comprehensive solution, combining small size, easy installation, and high security. These rings incorporate notches or indentations around the inner or outer diameter, ensuring the ring remains securely in place, even when vibrations or dynamic loads are present.

Self-locking rings can operate without grooves or complex machining in the mating components. This simplifies the “push-on” design and manufacturing process, making them an efficient choice for applications that

demand simplicity without compromising performance.

Spiral retaining rings serve as an artificial shoulder seated within a groove on a shaft or housing. This design ensures precision and stability in mechanical assemblies.

What sets spiral rings apart is their coiled structure, which grants them an exceptional degree of flexibility for sizing and material selection. In multiple-turn construction, the ring provides 360-degree contact with the groove.

Spiral rings ensure strong retention capabilities without the need for assembly lugs.

They’re also easy to install and remove, requiring no specialized tools.

When selecting a retaining ring, the choice of ring style can significantly influence the outcome of a project. Fortunately, there are several options to meet your unique

Spiral retaining rings

requirements.

Selecting the Optimal Washer Flat: Generally used for load disbursement Tab/Lock: Designed to effectively lock an assembly into place Finishing: Often found on consumer products Wave: For obtaining loads when the load is static or the working range is small Belleville: Delivers the highest load capacity of all the spring washers Fender: Distributes a load evenly across a large surface area Shim Stacks: Ideal for simple AND complex applications

Boker’s Inc. 3104 Snelling Avenue Minneapolis, MN 55406-1937 Phone: 612-729-9365 TOLL-FREE: 800-927-4377 (in the US & Canada)

bokers.com

38

December 2023

rings – fastener hb december 2023 v7 final.indd 38

www.fastenerengineering.com

DESIGN WORLD

12/11/23 10:11 AM

J.W. Winco, Inc. Spring Loaded Devices from JW Winco When you need to align, hold, or latch different parts of equipment together, you need a spring loaded device.These locking systems are designed to facilitate repetitive positioning operations on machines and equipment or parts undergoing machining. Spring loaded devices create a secure connection with limited play. JW Winco has many different versions and types for your application requirement.

Check out www.jwwinco.com to find out more!

J.W. Winco, Inc. Phone: 800.877.8351 sales@jwwinco.com www.jwwinco.com

Wide variety of spring to meet your innovation needs When it needs a specific spring to empower mechanical function of your product for best performance, such as Tensioning & Loading, Counterbalancing, Retrieving & Returning, Drive Motor, you are welcome to contact design engineer of Ming Tai Industrial Company for best solution. Based on 60 years manufacturing experience of steel strip spring, well experienced engineers of Ming Tai Industrial Company are capable to provide you with the best solution to meet your innovation needs.

Check out www.powerspring.com.tw for more interesting innovation stories!

Ming Tai Industrial Co., Ltd. No. 250, Sing Jhong Road Tamsui, New Taipei City 251 Taiwan Phone: 886-2-26228651 Fax: 886-2-26220202 E-mail: mtis@powerspring.com.tw

DESIGN WORLD

rings – fastener hb december 2023 v7 final.indd 39

www.fastenerengineering.com

December 2023

39

12/11/23 10:11 AM

NBK Acquired Solid Spot’s Plastic Fastener Business and Expanded Lineup NBK is a manufacturer of Specialty Screws including Plastic Fasteners.

In this April, NBK acquired Solid Spot LLC’s plastic fastener business and then, more various product lineup are available such as PEEK, RENY, PC, PVDF, PTFE, POM, etc.

NBK manufactures not only plastic screws but also low profile (low head), miniature size(less than M3), vacuum application, anti-galling, chemical resistance, non-magnetic, and more.

Flexible customization is available.

NBK America LLC 307 East Church Road, Suite 7 King of Prussia, PA 19406 Phone: 484-685-7500 https://www.nbk1560.com/en-US/

Assemble Faster with SLIC Pins Pin and Cotter All-In-One Eliminates Cotters, Clips, Nuts Speeds Assembly Time No Tools Needed Safer Retention, More Secure As Strong as Corresponding Cotters

The SLIC Pin from Pivot Point features a strong, springloaded plunger that acts as an automatic cotter. Upon insertion, the plunger automatically ramps down to pass through the application, springing back up to lock the pin in place. More consistent and easier to install, SLIC Pins eliminate the wasted motion to install a cotter, clip or nut. With separate pin/clip systems, clips can be mis-installed, forgotten altogether, or fall off later. The one-piece design of a SLIC Pin eliminates those risks, reducing product failures in the field and leading to a more consistent product. Manufactured on automated equipment, SLIC Pins are affordable, making them an ideal solution for optimizing high-volume assembly.

Tens of millions of SLIC Pins are installed each year, touching every industry and saving countless hours.

Explore SLIC in your application today.

40

December 2023

rings – fastener hb december 2023 v7 final.indd 40

www.fastenerengineering.com

Pivot Point, Inc. Tel +1 800 222-2231 Email: mail@pivotpins.com www.pivotpins.com/SLIC

DESIGN WORLD

12/11/23 10:11 AM