90
EMAIL TIPS A Learning Publication from Full Spectrum Diagnostics
Vol. 90 March 2013
New TWF Wall Chart
Understanding the Planetary Gearbox
EMAIL TIPS Volume 90 March 2013
4
Perspectives
2013 Training Schedules
Recent trends in Vibration Analysis training indicate that students are favoring shorter sessions that focus in specific aspects of analysis. Formal 3-4 day seminars tend to pack a lot of information into short blocks that might not be adequately absorbed by the student. The solution might not be to repeat the course, or just proceed to the next level. Rather, many students benefit from “concentrated” courses on specific concepts that are eluding them.
CORE TRAINING SERIES: ASNT: Intro (IVA) – VAI – VAII – VAIII ISO: Intro (Cat I) – Cat II – Cat III – Cat IV
Full Spectrum Diagnostics fills this gap with short (2-day) seminars on Spectrum Analysis, Time Waveform Analysis, Phase Analysis and hardware specific Rolling Element Bearing & Gear Analysis. These courses also benefit the student by contributing formal classroom hours required by ASNT and ISO for certification at VA-III (Cat IV) levels. See the training schedules included in this publication.
This Month’s Features: Planetary Gearbox Tips Real Data: Compressor Pulsations Real Measurements: Natural Frequency Mass Modification 2013 Training Schedules New Time Waveform Wall Chart
CONCENTRATED TRAINING TRACK: • Concentrated Time Waveform • Concentrated Spectrum Analysis • Concentrated Phase Analysis • Concentrated Rolling Element Bearings & Gear Analysis Concentrated Courses Earn ASNT VAIII & ISO Cat IV Hours
SPECIALTY & ADVANCED TRAINING • ODS/Modal • Precision Balancing • On-site Mentoring
Another Look at the Cover: The cover image shows a 1.6 MW Wind Turbine that was experiencing bearing problems within the planetary gearbox. The gearbox included four rotating shafts supported by nine rolling element bearings and three sets of meshing gears (including a planetary set). To define and understand the bearing signatures required an understanding of the entire gearbox. The [95:1] gear ratio required both high and low speed vibration analysis techniques, Time Waveform analysis, and ultrasonic analysis. Adding in the planetary system and things get real interesting. More analysis details inside.
GEARBOX TIP The analysis of “Planetary” or “Epicyclic” Gearboxes are not the most “straight forward” of tasks. Just following the step-by-step directions can be challenging. After analysis the hard way, a simplified table was discovered online that makes analysis much easier. The table outlines the seven (7) dominant configurations of these gearbox systems. Plugging tooth counts in the formulas allows the user to calculate the relative speed of the gears with respect to the reference (known) driving member speed.
TRING = 75 TPLANET = 28 TSUN = 18
Step 1: Choose planetary configuration.
SRATIO = [(R+S)/S] = [(75+18)/18] = 5.167 PRATIO = [(R/P)] = [(75/28)] = 2.678
Review of the gear system should indicate a stationary Gear, a Driving Member, and a Driven Member.
Step 3: Scale to Driving Member Speed.
In this case, the Driving Member is the Turbine Input. The Ring Gear is Fixed in the gearbox housing. The Sun Gear is the Driven Gear. The system corresponds to Table Configuration #3. Step 2: Input the Gear Tooth counts. The tooth counts (not the Gear Ratios) are important for this analysis. If a drawing cannot be found that discloses the tooth counts, the analyst must gain access to the gearbox and manually count the teeth on each Sun, Planet, and Ring gear.
The table results are presented as a ratio of the driving member rotational speed. For an Input Speed of 19 RPM (Planet Carrier) the Output (Sun Gear) speed is 5.167 x 19 RPM or 98.2 RPM. The Planet Gear rotating speed is 2.678 x 19 RPM or 50.9 RPM. There is only ONE Gear Meshing Frequency generated in this system: GMF = 19 x 75T = 1425 CPM GMF = 50.9 x 28T = 1425 CPM GMF = (98.2 – 19) x 18T = 1425 CPM
REAL L DATA: The Od dd and Unccommon
REAL MEASU UREMENT TS: Quickk and Dirty
The Tim me Waveform data belo ow was colle ected on a set of five-stage f R Reciprocating g Compresssors. The sister units were e virtually identical and a both ng at norm mal condition ns. The waveforms w operatin were setup to cap pture six rev volutions of the main haft. The re esulting plotts from cylin nder #4 in drive sh the axxial direction n showed significantlyy different profiless from the tw wo units. Ea ach of the units u were found to pulse att the 300 RPM turnin ng speed; howeve er the east compressor c shows s an assymmetric pattern. Addition nal measure ements on the unit suggessted that the e outboard cylinder c asse embly bolt pattern was likelyy becoming g loose. The offset pattern suggests a lack of res sistance to motion in T The period defines the source one direction. ncy (300 RPM). R The ere was so ome high frequen frequen ncy ringing frrom internal impacting.
Full Spectrum S Diagnostics was w asked to t provide analyssis on a Fu uel Oil Feed d Pump at a nearby refinerry. This pu ump was experiencing e g elevated vibratio on at its Blade B Passin ng Frequen ncy (BPF). The am mplitude levvels were tho ought to be related to fuel oil o temperattures. Da ata sets we ere being collectted at sevveral processs points where oil temperature was varied. In the t idle time e between the prrocess setup p points the ere was tim me to take other operating measureme m nts. Since e the unit could not be sh hut down for f natural frequency testing g, an on-line e modification via chang ge of mass was suggested s a and approve ed. This change c of mass involved the e addition of roughly 200 0 lbs to the Pump Outboard Bearing ped destal. The e 200 lbs came in the form m of the maintenance m e engineer assisting with the data collection. A baseline measu urement indicated a ve ertical vibration at the Blade Passing Fre equency (30 00 Hz) of 0.9 970 ips at one lo ocation on th he bearing housing. h Th he addition of masss increased d the vibrattion amplitud de to 1.48 ips (ap pproximatelyy +50% change). When n the mass was re emoved the vibration level dropped d to 1.19 1 ips. The test t was relatively howeve crude; er the change affected only the magnittude of th he BPF peak. The indiccation is that th he bearing housing likely has a natural freque ency slightlyy above the BP PF frequenccy. The data from this test is presen nted in below w.
www.fu ullspec.net
www.fu fullspec.net
B BLACK (0.970 ipps) RED (1.48 ips) BLUE (1.119 ips)
2013 CORE VIBRATION TRAINING SCHEDULE
2013 SPECIALTY VIBRATION TRAINING SCHEDULE
Implementing A Successful PdM Program (1)
Modal & ODS Analysis (2)
AUG 27-28
NOV 19-21 Cedar Rapids, IA 2013-ODS-02 Call for In-Plant Training Course! 763-577-9959 Tuition: $ 1,695.00 / 3-day Format One Month ME’scope Software Included
St. Paul, MN
2013-PdM-01
Tuition: $ 975.00 / 2-day Format Proficiency Test: Included Introduction to Vibration Analysis (CAT I)(1) In-Plant by Request
Concentrated Time Waveform Analysis(1) APR 16-17 Wheeling, WV 2013-TWF-01 JUN 25-26 St. Paul, MN 2013-TWF-02 SEP10-11 Cedar Rapids, IA 2013-TWF-03 Tuition: $ 975.00 / 2-day Format Proficiency Test: Included
Tuition: $ 975.00 / 2-day Format Proficiency Test: Included Vibration Analysis (VAI/CAT II)(1) APR 02-05 MAY 14-17 JUL 09-12 DEC 10-13
St. Paul, MN Cedar Rapids, IA Quakertown, PA Charlotte, NC
2013-VA1-03 2013-VA1-04 2013-VA1-05 2013-VA1-06
Concentrated Spectrum Analysis(1)
Tuition: $ 1,350.0 / 3-day Format Certification Exam: $ 200.00
JUL 30-31 Vancouver, WA 2013-CSA-02 AUG 13-14 St. Paul, MN 2013-CSA-03 SEP 24-25 Cedar Rapids, IA 2013-CSA-04 Tuition: $ 975.00 / 2-day Format Proficiency Test: Included
Vibration Analysis (VAII/CAT III)(1)
Concentrated Phase Analysis
MAY 07-10 MAY 21-24 JUN 04-07 JUN 11-14 OCT 01-04
JUL 16-17 Youngstown, OH 2013-CPA-01 OCT 08-09 Cedar Rapids, IA 2013-CPA-02 Tuition: $ $ 975.00 / 2-day Format Hands-on Exercises: Included
Wheeling, WV Chicago, IL Eugene, OR Cedar Rapids, IA St. Paul, MN
2013-VA2-02 2013-VA2-03 2013-VA2-04 2013-VA2-05 2013-VA2-06
Concentrated REB & Gear Fault Analysis(1)
Tuition: $ 1,450.00 / 3-day Format Certification Exam: $ 200.00 Vibration Analysis (VAIIIa/CAT IVa) (1) NEW! OCT21-25
St. Paul, MN
2013-TVA-01
Tuition: $ 1,650.00 / 4 1/2-day Format Certification Exam: $ 200.00 Vibration Analysis (VAIIIb/CAT IVb) (1) NEW! NOV 04-08
St. Paul, MN
APR 23-24 Cedar Rapids, IA 2013-BGA-02 JUN 18-19 Rock Island, IL 2013-BGA-03 Tuition: $ 975.00 / 2-day Format Proficiency Test: Included
2013-PVA-01
Tuition: $ 1,650.00 / 4 1/2-day Format Certification Exam: $ 200.00
Vibration Analysis For Motor Repair Shops(1) OCT 15-17 Columbia, SC 2013-VAM-01 DEC 03-05 New Orleans, LA 2013-VAM-02 Tuition: $ 1,295.00 / 3-day Format Hands-on Exercises: Included Precision Balancing(1) APR 09-11 Cedar Rapids, IA MAY 28-30 Milwaukee, WI SEP 17-19 Thornton, IL NOV 12-14 Chillicothe, OH Tuition: $ 1,295.00 / 3-day Format Hands-on Exercises: Included
2013-BAL-02 2013-BAL-03 2013-BAL-04 2013-BAL-05
ISN’T IT ABOUT TIME FOR A REAL TIME WAVEFORM WALL CHART?
Full Spectrum Diagnostics announces a new addition to our family of charts and guides with the Time Waveform Analysis Wall Chart. This full-color laminated 33” x 42” chart includes the full gambit of waveform patterns, classic orbits, and diagnostic techniques to support any vibration analyst. A list of FSD’s top 25 Waveform Tips are included in short, easy to interpret blocks of useful information. Order now at www.fullspec.net online store! $99.90 each!
THE VIBRATIO V ON FAUL LT GUIDE E The Vib bration Faultt Guide pock ket reference e was first introducced in Janua ary of 2005. Since 2005 5 we’ve average ed sales of nearly n 1000 units per ye ear! The guide can be purchased p in n singles or bulk b sets, as requ uested. Man ny customers s order unitss in quantitiies of 100-10 000 and opt to personalize the front an nd back cove ers with their logo and company contactt information n. They are used as training aids and disstributed with h their produ ucts as a parrt of marketiing campaig gns. No mattter whose name & logo appears on the cover, it’s all Full F Spectrum m Diagnostic cs know how w on the inside! The 110 pa ages define over o 40 vibra ation related faults, signa al processing g formulas, severity s charts, and alarm band b profiles s. A handy glossary g definess 50 common n vibration te erms Order now n at: http://www.fullsp pec.net/store e.html Or by Email E @ mod dalguy@aol.com Or by Phone P @ (61 12) 875-9959 9
BULK DIS SCOUNTS & BUNDLE PACKA AGES AVA AILABLE!
THE VIBRATIO V ON TECH HNIQUES GUIDE The Vib bration Ana alysis Techn niques Guid de is a 108-pag ge pocket siized informa ation treasure e trove. Informa ation on doze ens of analy ysis techniqu ues, specificcations and data d presenttation formats are included. ur next If you liked the Vibrration Faultt Guide, you hould be the Vibration educatiional step sh Analys sis Techniqu ues Guide get g yours no ow at:
Order now n at: http p://www.fullspec.net/store e.html Or by Email E @ mod dalguy@aol.com Or by Phone P @ (612) 875-995 59
BULK DIS SCOUNTS & BUNDLE PACKA AGES AVA AILABLE!
THE VIBRATIION ANALYSIS WALL W CHA ART The Vibration V Ana alysis Wall Chart C is a 46 6” x 36” Full-Color Laminated Referrence for you ur drab officce wall. The e overall Alarm cha arts in the center of th he chart are e surrounde ed by group pings of ove er 40 dominant rotating g machinery faults.. The faultt groupings include fre equency con ntent and dominant d dirrectional ressponse thatt he analyst to o “narrow-do own” the pottential source es and zero-in on curren nt vibration problem. p effectively allow th n combined with the Vib bration Fault Guide, the e Vibration Analysis Wall W Chart co ompletes the e diagnosticc When analyssis loop. We eather you require r one chart c or a ne eed to wall-p paper your office, we can n help!
ore.html Orderr now at: Htttp://www.fulllspec.net/sto Or byy Phone @ (612) 875-99 959
BU ULK DISC COUNTS & BUNDL LE PACKAGE ES AVAIL LABLE!
THE VIBRAT TION ANA ALYSIS PERIODIC P C TABLE Thiss Full Color Laminated L 13 x 17 inch card-stock table provide es a “quick-lo ook” method d of distinguishing one machinerry fault from another and d suggests Diagnostic D T Tests or forrmula that may be use ed to build a case and make m the call! Thiss Chart is a “Logical” “ ana alysis tool th hat classifiess vibration prroblems by Frequency F C Content and Directional Response. The potentia al vibration sources s are instantly red duced based d on the analyst’s a current measu urement data a. The Table e “forces” the e user to think logically and a classify faults acccordingly. Indivvidual Faultss are Foot Note Referen nced to the Vibration V Fa ault Guide fo or a more de etailed revie ew. If you th hink the Vibrration Faultt Guide is va aluable, you ur next educa ational step should be th he Vibration n Analysis Periodic P Ta able! Get yours now at: a www.fulllspec.net, or o by phone at a 612-875-9 9959
BULK DISCOUNTS & BUNDL LE PA ACKAGES S AVAILA ABLE!
INSTRUCTORS:
Full Spectrum Diagnostics’ Lead Instructor & Seminar Author is Dan Ambre. Dan is a graduate of The University of Iowa with a Bachelor’s degree in Mechanical Engineering, and has completed additional graduate level course work in Engineering Dynamics from The University of Illinois at Chicago, and Florida Atlantic University. Dan is a Certified Vibration Analysis Level III Instructor (Category IV) with over 16 years of Vibration Training and Certification Experience. Dan’s 25+ years of vibration experience in the Aviation & Aerospace Industries comes from positions at Sundstrand Aviation Corporation and Pratt & Whitney (United Technologies Corporation). This fieldwork includes Vibration & Acoustic testing, Rotor Dynamics analysis of high speed Rotor Systems, Experimental Modal, and Finite Element Analysis. His consulting experience base comes from positions at Technical Associates and Full Spectrum Diagnostics, which he founded in June of 2000. He is a Registered Professional Engineer in the States of North Carolina and Minnesota.
In 2004, after years of close association, Louis G. Pagliaro joined Full Spectrum Diagnostics. Lou fulfills multiple roles as our Seminar Sales Coordinator, Senior Instructor and course content co-author. Lou is a certified Level III Vibration Analyst (since 1996) and was recently re-certified by American Society of Nondestructive Testing as an ASNT PdM Level III in Vibration Analysis (Category IV). He has over 30 years of varied industrial experience, including Maintenance Management, Vibration Analysis, Vibration Training, Certification, and course development in areas of Noise Control, Precision Maintenance, Precision Alignment, Preventive Maintenance, and Maintenance Skills Enhancement. His worldwide teaching credentials include instruction of TAC, Update International, CSI, Entek and SKF customers in eight countries. Louis is a graduate of Niagara College in Welland, Canada. Lou can be contacted by phone at (704) 620-1028, or via Email at Lpagl@aol.com.
Dan can be contacted by phone at (612) 875-9959, or via Email at ModalGuy@aol.com
ModalGuy@aol.com
LpagL@aol.com
Shipya ard Crane Hoist H Syste ems
Boile er Feed Pump
pectrum Diagnostics s is a Certifiied Full Sp Softwa are Represe entative and d training partner p with Viibrant Tech hnology, In nc. the makkers of ME’sco ope Animattion Software. ME’sco ope is a pow werful visua al tool for any a Vibratio on Analyst.. When you u need to get g your point across a to managementt nothing be eats a visual presentatio on. From Operating O Deflection Shape (ODS), to Modal Analysis, to Accoustic diagno ostics, ME’sscope is the e way to go! IF YOU U CAN’T SE EE IT…… …..… YOU Y CAN’T T FIX IT!
Refinery Compresso C or & Founda ation