TROUBLESHOOTING GUIDE DRIVE SHUTDOWN ... - Richards …

1 Step 1 Describe the problem What is wrong? When did it happen? How often does it happen? What is the DRIVE application? Have the machine operations or output changed? What kind of belt (s) are you using? What are your expectations for belt performance inthis application?Step 2 Identify symptoms and record observations of anything Symptoms Check List (Check those you observe) Premature belt Failure Broken belt (s) belt (s) fail to carry load (slip). No visible reason Edge cord failure belt delamination or undercord separation Severe or Abnormal belt Wear Wear on belt top surface Wear on top corners of belt Wear on belt sidewall Wear on belt bottom corners Wear on bottom surface of belt Undercord cracking Burn or hardening on bottom or sidewall belt surface flaking, sticky or swollen belt stretch Extensive hardening of belt exterior Banded (Joined)

2 belt Problems Tie-band separation Top of tie-band frayed, worn or damaged Band comes off DRIVE One or more ribs run outside of pulley V- belt Turns Over or Jumps off Sheave Single belt One or more belts in a set Joined or banded belts belt Stretches Beyond Take-Up Single belt Multiple belts stretch unequally All belts stretch equallyDRIVE SHUTDOWN & THOROUGH INSPECTION24 TROUBLESHOOTING GUIDEAll V- belt Drives belt Noise Squeal or chirp Slapping noise Rubbing sound Grinding Unusually loud DRIVE Unusual Vibration Belts flopping Excessive vibration in DRIVE system Problem With Pulleys Broken or damaged Severe, rapid groove wear Problems With DriveComponents Bent or broken shafts Damaged guard Problems With Take Up Make sure you are using Gates belts Not all belts are sameAll Synchronous belt Drives belt Problems Unusual noise Tension loss Excessive belt edge wear Tensile break Cracking Premature tooth wear Tooth shear belt ratcheting Land area worn Hot Bearings Performance Problems Incorrect driveN speeds Sprocket Problems Flange failure Unusual wear Performance Problems belt tracking problems Excessive temperature: bearings, housings,shafts, etc.

3 Shafts out of sync VibrationTROUBLESHOOTING GUIDETROUBLESHOOTING GUIDE25 DRIVE SHUTDOWN & THOROUGH INSPECTION26 Symptoms Broken belt (s) Belts fail to carry load, no visiblereason Edge cord failure belt de-lamination or undercordseparationProbable Cause1. Under-designed drive2. belt rolled or pried onto sheave3. Object falling into drive4. Severe shock load1. Underdesigned drive2. Damaged tensile member3. Worn sheave grooves4. Center distance movement1. Pulley misalignment2. Damaged tensile member1. Too small sheaves2. Use of too small backside idlerCorrective Action1. Redesign, using Gates Use DRIVE take-up Provide adequate guard or Redesign to accommodateshock Redesign, using Gates Follow correct installation Check for groove wear; replaceas Check DRIVE for center distancemovement during Check alignment and Follow correct installation Check DRIVE design, replace withlarger Increase backside idler toacceptable SUMMARY TABLEP remature belt FailureDRIVE SHUTDOWN & THOROUGH INSPECTION27 Symptoms Wear on top surface of belt Wear on top corner of belt Wear on belt sidewalls Wear on bottom corner of belt Wear on bottom surface of belt Undercord crackingProbable Cause1.

4 Rubbing against guard2. Idler malfunction1. belt -to-sheave fit incorrect (belttoo small for groove)1. belt slip2. Misalignment3. Worn sheaves4. Incorrect belt1. belt -to-sheave fit incorrect2. Worn sheaves1. belt bottoming on sheave groove2. Worn sheaves3. Debris in sheaves1. Sheave diameter too small2. belt slip3. Backside idler too small4. Improper storageCorrective Action1. Replace or repair Replace Use correct Retention until slipping Realign Replace Replace with correct belt Use correct belt -to-sheave Replace Use correct belt /sheave Replace Clean Use larger diameter Use larger diameter Don t coil belt too tightly, kink heat and direct SUMMARY TABLES evere or Abnormal V- belt WearDRIVE SHUTDOWN & THOROUGH INSPECTION28 Symptoms Involves single or multiple beltsProbable Cause1.

5 Shock loading or vibration2. Foreign material in grooves3. Misaligned sheaves4. Worn sheave grooves5. Damaged tensile member6. Incorrectly placed flat idler7. Mismatched belt set8. Poor DRIVE designCorrective Action1. Check DRIVE design. Use GatesPowerBand belts or PowerCable Shield grooves and Realign the Replace Use correct installation and beltstorage Carefully align flat idler on slackside of DRIVE as close as possi-ble to driveR Replace with new set of not mix old and Check for center distance stabili-ty and vibration Undercord or sidewall burn orhardening belt surface hard or stiff belt surface flaking, sticky or swollenProbable Cause1. belt slipping2. Worn sheaves3.

6 Underdesigned drive4. Shaft movement1. Hot DRIVE environment1. Oil or chemical contaminationCorrective Action1. Retension until slipping Replace Refer to Gates DRIVE Check for center Improve ventilation to Do not use belt sources of oil, greaseor chemical SUMMARY TABLES evere or Abnormal V- belt Wear Turn Over or Come Off DriveDRIVE SHUTDOWN & THOROUGH INSPECTIONPROBLEM/SOLUTION SUMMARY TABLEBelt Stretches Beyond Available Take-UpBelt NoiseUnusual VibrationSymptoms Multiple belts stretch unequally Single belt , or where all beltsstretch evenlyProbable Cause1. Misaligned drive2. Debris in sheaves3. Broken tensile member or corddamaged4. Mismatched belt set1. Insufficient take-up allowance2.

7 Grossly overloaded or underdesigned drive3. Broken tensile membersCorrective Action1. Realign and retension Clean Replace all belts, install Install matched belt Check take-up. Use allowancespecified in Gates design Redesign Replace belt , install belt squeals or chirps Slapping Sound Rubbing sound Grinding sound Unusually loud driveProbable Cause1. belt slip2. Contamination1. Loose belts2. Mismatched set3. Misalignment1. Guard interference1. Damaged bearings1. Incorrect belt2. Incorrect Tension3. Worn sheaves4. Debris in sheavesCorrective Action1. Clean belts and Install matched belt Realign pulleys so all belts shareload Repair, replace or redesign Replace, align & Use correct belt size.

8 Use cor-rect belt tooth profile for sprock-ets on synchronous Check tension and adjust3. Replace sheaves4. Clean sheaves, improve shield-ing, remove rust, paint, orremove dirt from Belts flopping Unusual or excessive vibration Probable Cause1. Loose belts (under tensioned)2. Mismatched belts3. Pulley misalignment1. Incorrect belt2. Poor machine or equipmentdesign3. Pulley out of round4. Loose DRIVE componentsCorrective Action1. Install new matched Align pulley1. Use correct belt cross section inpulley. Use correct tooth profileand pitch in Check structure and brackets foradequate Replace with non-defective Check machine components andguards, motor mounts, motorpads, bushings, brackets andframework for stability adequatedesign strength, proper mainte-nance and proper SHUTDOWN & THOROUGH INSPECTIONPROBLEM/SOLUTION SUMMARY TABLEP roblems With SheavesSymptoms Broken or damaged sheave Severe Groove WearProbable Cause1.

9 Incorrect sheave installation2. Foreign objects falling into drive3. Excessive rim speeds4. Incorrect belt installation1. Excessive belt tension2. Sand, debris or contamination3. Wrong beltCorrective Action1. Do not tighten bushing bolts beyondrecommended torque Use adequate DRIVE Keep pulley rim speeds belowmaximum recommended Do not pry belts onto Retension, check DRIVE Clean and shield DRIVE as well Make sure belt and sheave com-bination is With Other DRIVE ComponentsSymptoms Bent or broken shaftProbable Cause1. Extreme belt overtension2. Overdesigned DRIVE *3. Accidental damage4. Machine design error5. Accidental damage to guard orpoor guard design6. Pulley mounted too far awayfrom outboard bearingCorrective Action1.

10 Retension2. Check DRIVE design, may need touse smaller or fewer Redesign DRIVE Check machine Repair, redesign for Move pulley closer to ProblemsSymptoms Incorrect driveN speedProbable Cause1. Design error2. belt slipCorrective Action1. Use correct driveR/driveN sheavesize for desired speed Retension synchronous BearingsSymptoms DRIVE needs overtensioning Sheaves too small Poor bearing condition Sheaves too far out on shaft belt slippageProbable Cause1. Worn grooves - belts bottomingand won t transmit power untilovertensioned*2. Improper tension1. Motor manufacturer s sheavediameter recommendation notfollowed1. Bearing underdesigned2. Bearing not properly maintained1.