TROUBLESHOOTING (in order of probable occurrence)
A. Conveyor runs to one side at given point on structure.
- Buildup of material on idlers: remove accumulation; improve maintenance, install scrapers or other cleaning devices.
- Sticking idlers: free idlers and improve maintenance and lubrication.
- Idlers or pulleys out-of-square with center line of belt: readjust idlers in affected area.
- Conveyor frame of structure crooked: straighten in affected area.
- Idler stands not centered on belt: readjust idlers in affected area.
- Structure not level: level structure in affected area.
B. Particular section of belt runs to one side at all points on conveyor.
- Belt not joined squarely: remove affected splice and resplice.
- Bowed belt: for new belt this condition should disappear during break-in; in rare instances belt must be straightened or replaced; check storage and handling of belt rolls.
C. Belt runs to one side for long distance or entire length of conveyor.
- Belt running off-center around the tail pulley and through the loading area: install training idlers on the return run prior to tail pulley.
- Off-center loading or poor loading: adjust chute to place load on center of belt; discharge material in direction of belt travel at or near belt speed.
- Buildup of material on idlers: remove accumulation; improve maintenance, install scrapers or other cleaning devices.
- Idlers or pulleys out-of-square with center line of belt: readjust idlers in affected area.
- Conveyor frame of structure crooked: straighten in affected area.
- Idler stands not centered on belt: readjust idlers in affected area.
D. Belt runs off at tail pulley.
- Belt running off-center around the tail pulley and through the loading area: install training idlers on the return run prior to tail pulley.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Idlers or pulleys out-of-square with center line of belt: readjust idlers in affected area.
E. Belt runs off at head pulley.
- Pulley lagging worn: replace pulley lagging.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Idlers or pulleys out-of-square with center line of belt: readjust idlers in affected area.
- Idler stands not centered on belt: readjust idlers in affected area.
F. Belt slip.
- Insufficient traction between belt and pulley: lag drive pulley; increase belt wrap; install belt cleaning devices.
- Pulley lagging worn: replace pulley lagging.
- Counterweight too light: add counterweight or increase screw take-up tension to value determined from calculations.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Sticking idlers: free idlers and improve maintenance and lubrication.
G. Belt slip on starting.
- Insufficient traction between belt and pulley: lag drive pulley; increase belt wrap; install belt cleaning devices.
- Counterweight too light: add counterweight or increase screw take-up tension to value determined from calculations.
- Pulley lagging worn: replace pulley lagging.
H. Excessive belt stretch.
- Improper belt installation causing apparent excessive belt stretch: pull belt through counterweight with a tension equal to at least empty running tension; run belt in with mechanical fasteners.
- Improper initial positioning of counterweight in its carriage causing apparent excessive belt stretch: check Goodyear Handbook of Belting for recommended initial position.
- Insufficient counterweight travel: consult Goodyear Conveyor and Elevator Belt Selection Manual for recommended minimum distances.
- Tension too high: increase speed, same tonnage; reduce tonnage, same speed; reduce friction with better maintenance and replacement of damaged idlers; decrease tension by increasing arc of contact or go to lagged pulley; reduce CWT to minimum amount.
- Counterweight too heavy: lighten counterweight to value required by calculations.
System underbelted: recalculate belt tensions and select proper belt.
I. Grooving, gouging or stripping of top cover.
- Skirt boards improperly adjusted or of wrong material: adjust skirt board supports to minimum 1" between metal and belt with gap increasing in direction of belt travel; use skirt board rubber (not old belt).
- Belt spanking down under load impact: install cushion idlers.
Material hanging up in or under chute: improve loading to reduce spillage; install baffles; widen chute.
- Impact of material on belt: reduce impact by improving chute design; install impact idlers.
J. Excessive top cover wear, uniform around belt.
- Dirty, stuck, or misaligned return rolls: remove accumulations; install cleaning devices, use self-cleaning return rolls, improve maintenance and lubrication.
- Cover quality too low: replace with belt of heavier cove gauge or higher quality rubber.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Off-center loading or poor loading: adjust chute to place load on center of belt; discharge material in direction of belt travel at or near belt speed.
- Excessive sag between idlers causing load to work and shuffle on belt as it passes over idlers: increase tension if unnecessarily low; reduce idler spacing.
K. Severe pulley cover wear.
- Sticking idlers: free idlers and improve maintenance and lubrication.
- Slippage of drive pulley: increase tension thru screw takeup or add counterweight; lag drive pulley; increase arc of contact.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Material trapped between belt and pulley: install plows or scrapers on return run ahead of tail pulley.
- Bolt heads protruding above lagging: tighten bolts; replace lagging; use vulcanized-on lagging.
- Excessive forward tilt of trough rolls: reduce forward tilt of idlers to no more than 2 (degrees symbol) from vertical.
L. Longitudinal grooving or cracking of bottom cover.
- Sticking idlers: free idlers and improve maintenance and lubrication.
- Material spillage and buildup: improve loading and transfer conditions; install cleaning devices; improve maintenance.
- Slippage of drive pulley: increase tension thru screw takeup or add counterweight; lag drive pulley; increase arc of contact.
- Pulley lagging worn: replace pulley lagging.
M. Covers harden or crack.
- Heat or chemical damage: use belt designed for specific condition.
- Improper storage or handling: refer to Goodyear for proper storage and handling instructions.
N. Cover swells in spots or streaks.
- Spilled oil or grease, over-lubrication of idlers: improve housekeeping; reduce quantity of grease used; check grease seals.
O. Belt breaks at or behind fasteners; fasteners pull out.
- Fastener plates too long for pulley size: replace with smaller fasteners; increase pulley size.
- Wrong type of fastener, fasteners too tight or too loose: use proper fasteners and splice technique; set up schedule for regular fastener inspection.
- Tension too high: increase speed, same tonnage; reduce tonnage, same speed; reduce friction with better maintenance and replacement of damaged idlers; decrease tension by increasing arc of contact or go to lagged pulley; reduce CWT to minimum amount.
- Heat or chemical damage: use belt designed for specific condition.
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