Conviber Logo
celebrating-47-years
4 Square Icon

Troubleshoot

Conveyor System

Troubleshooting your Conveyor Systems

Common Conveyor Problems Addressed Below

  • Tracking or training
  • Crooked (new) belt
  • Excessive Wear on top cover
  • Wearing or fraying of belt edge
  • Wear bottom cover
  • Fastener failures
  • Narrowing of Belt
  • Shrinking of Belt
  • Stretching of Belt
  • Too frequent take-up adjustment
  • Ply separation
  • Stalling (jerking)
  • Load slipping or sticking
  • Slipping of belt on drive
  • Soft and tacky cover
  • Cracking-Bottom cover (transverse cracks)
  • Cracking of top cover
  • Deterioration in storage
  • Transverse breaks at belt edge
  • Parallel Breaks in belt edge or star breaks
  • Traverse breaks directly behind fasteners
  • Fasteners pulling out
  • Splice failure
  • Top cover grooved and gouged
  • Longitudinal splicing failure

Problem: Tracking or training

Cause

Solution

  • Mechanical malfunction

Proper alignment of pulleys on conveyor frame.

  • Crooked splice

Square belt end, repair splice.

  • Crooked belt

Replacement may be required.

  • Material build-up on pulleys

Recommend routine maintenance or mechanical cleaning devices.

  • Off-center loading

Change feeder design or replace belt with more bulk. Check belt manufacturer’s specs.

  • Excessive pulley crown

Refer to CEMA Standard 402-1964 or check with technical of belt manufacturer.

  • Distorted belt due to run off or accidental damage

Replacement of belt indicated.

Problem: Crooked (new) belt

Cause

Solution

  • Uneven moisture absorption of cotton fabric

Check with source for reconditioning and consider replacement with polyester or nylon fabrics.

  • Crooked cut or warp not in line with belt travel

If belt will not run straight under tension, a replacement may be necessary. (Normally, if the fill yarn is not perpendicular to the line of travel, it will not affect ability to track the belt.

Problem: Wear - Excessive on top cover

Cause

Solution

  • Plows or skirt boards in contact with belt surface.

Adjust or redesign

  • Belt wiper or doctor blade in contact with belt surface

Frequent maintenance required for maximum belt life. Never use old conveyor belt as wiper.

  • Frozen return idlers or material build-up on return idlers

Free or replace. Frequent maintenance required.

  • Improper compound

Recheck environmental conditions and check with technical or belt manufacturer.

Problem: Wearing or fraying of belt edge

Cause

Solution

  • Improper tracking or training

Refer to “Tracking or training.”

  • Material build-up

Redesign or adjust loading conditions, scraper, plows and/or cleaning mechanisms.

  • Side loading

V-guide may be required or change direction of loading.

  • Material build-up on idlers or pulleys

Realign system, stiffer belt required or consider V-guide design or guide rollers.

Problem: Wear bottom cover

Cause

Solution

  • Rough or worn slider bed surface or pulleys

Replace worn surfaces or clean through routine maintenance procedures.

  • Belt slipping on drive pulleys

Increase take-up adjustment. Increase belt wrap on drive, lag drive.

  • Frozen idlers or pulleys

Free or replace

  • Material build-up on idlers or pulleys

Keep clean through routine maintenance or mechanical devices.

Problem: Fastener failures

Cause

Solution

  • Under belted

Recalculate tension requirement. Change belt recommendation or drive design.

  • Undersized pulleys

Replace pulleys or change belting recommendation

  • Improper fastener or application procedures

Check overall gauge of belt and system pulley sizes with fastener manufacturer’s recommendations.

  • Conditions too severe for mechanical lacing

Consider vulcanized splice, or change in drive or loading design.

Problem: Narrowing of Belt

Cause

Solution

  • Belt stretching

Indicates system underbelted. Recalculate tension requirement.

  • Fabric instability

Check all environmental conditions that might affect fabric service life.

Problem: Shrinking of Belt

Cause

Solution

  • Water absorption

Consider replacing cotton or rayon with nylon or polyester fabrics.

  • Heat memory of synthetic fabrics

Double check environmental heat factors, available take-up, position of take-up on installation and cleaning procedures. Refer to technical or belt manufacturer.

Problem: Stretching of Belt

Cause

Solution

  • Under belted

Recalculate tension requirement. Change belt recommendations or consider changing drive design.

  • Fabric instability

Check environmental conditions and consider replacing with nylon or polyester fabrics.

  • Excessive build-up on pulleys

Keep pulleys clean with routine maintenance or mechanical cleaning devices.

  • Excessive take-up force

Reduce tension to the point that belt will not slip or replace screw with automatic system.

Problem: Too frequent take-up adjustment

Cause

Solution

  • Under belted

Recalculate tension requirement.

  • Fabric instability

Recheck environmental conditions and consider replacement with nylon or polyester fabrics.

Problem: Ply separation

Cause

Solution

  • Pulleys too small

Replace with larger pulleys

  • Excessive pulley crown

Refer to CEMA Standard 402-1964 or check with technical of belt manufacturer.

  • Chemical attack

Check environmental conditions and refer to technical or belt manufacturer.

Problem: Stalling (jerking)

Cause

Solution

  • Improper slack side tension

Adjust take-up position. Consider lagging drive pulley and installing snub pulley to increase belt wrap on drive pulley.

  • In slider bed service-suction between belt and slider bed surface in presence of moisture

Weld 1/4″ or 1/2″ round rods to slider bed surface or perforate conveyor bed. Round off and smooth all surfaces in contact with belt.

Problem: Load slipping or sticking

Cause

Solution

  • Improper cover compound or type of surface of top cover.

Check with your distributor giving operational data and system profile.

Problem: Slipping of belt on drive

Cause

Solution

  • Improper slack side tension

Adjust take-up position and consider increasing wrap of drive with snub pulley and lagging drive pulley.

Problem: Soft and tacky cover

Cause

Solution

  • Improper compound for service

Check environmental conditions-especially oil and solvents. Refer to belt manufacturer’s complete operation and environmental data.

Problem: Cracking-Bottom cover (transverse cracks)

Cause

Solution

  • Slipping on drive pulley

Advance take-up pulley toward maximum position.

  • Under belted

Recalculate tension to select correct construction.

  • Undersize pulleys

Check all pulleys, especially high tension snub or reverse pulley.

Problem: Cracking of top cover

Cause

Solution

  • Heat

Determine surface temperatures and check against rated resistance of compound in service.

  • Weather or age cracking

Check rated resistance of compound in service.

  • Undersize pulley

Check minimum pulley recommendations of belt in service. Replace pulleys or change belt recommendations.

  • Underbelted

Recalculate tension. Change belt recommendation or alter drive design.

  • Shrinkage

Heat or chemicals causing loss of plasticisers and then elasticity.

Problem: Deterioration in storage

Cause

Solution

  • Mildew of fabric and/or compound

Always store belting in cool, dry area on racks supported by shafts through belt core. Suggest replacements made with nylon or polyester core.

Problem: Transverse breaks at belt edge

Cause

Solution

  • Folding up of belt edges

Check tracking. Increase lateral clearance.

  • Belt mildew

Use belt with mildew inhibitor in rubber compounds

  • Idler next to head pulley located too high or too close in relation to head pulley

Reposition final idler pulley.

Problem: Breaks in belt parallel to belt edge or star breaks in belt

Cause

Solution

  • Heavy lumps falling on belt or falling from too great a height

Reduce impact of material.

  • Material lodged between belt and pulley or stuck to back of belt

Return run should have scrapers ahead of tail pulley.

Problem: Traverse breaks directly behind fasteners

Cause

Solution

  • Belt fasteners too large for pulley size being used.

Replace with manufacturer’s recommended fasteners or change to large pulley size.

Problem: Fasteners pulling out

Cause

Solution

  • Fasteners wrong size or not tight

Replace fasteners and inspect regularly.

  • Belt too tight

Correct take-up tension.

  • Belt too thick for pulleys

Replace belting or switch to larger diameter pulleys.

  • Under belted

Reduce speed or use larger pulley to reduce “whipping” of belt around pulley. Switch to endless belt. Review engineering data and recalculate. Give special attention to fabric fill construction.

Problem: Splice failure

Cause

Solution

  • Belt too tight

Ease take-up tension

  • Belt carcass to thick for pulleys

Switch to larger diameter pulleys or replace with more flexible belt.

  • Belt speed too high

Reduce speed or increase pulley size.

  • Under belted

Recalculate tension requirement. Carefully examine failed splice, have adhesions checked, review step length.

Problem: Top cover grooved and gouged

Cause

Solution

  • Skirt boards are pressing against belt

Adjust skirt boards often Use all rubber – NEVER old belting.

  • Space between belt and skirt is too close to belt.

Adjustment to minimum clearance. taper so that space becomes greater toward head pulley so material can work out.

  • Material Jammed at chute

Improve delivery system to conveyor.

  • Metal sides of chute or skirts too close to belt

Adjust so gap between metal and belt increases in direction of belt travel to avoid jamming.

Problem: Longitudinal splicing failure

Cause

Solution

  • Exposure of heat or chemicals

Use higher resistant quality polymer and adequate skim between plies.

  • Pulley crowning causes stress and tears at tough on crown area

Improve or remove crown pulley.

  • Poor splice

Carefully examine splice failure, have adhesions checked.

6 Stocking Centers Provide You with Same or Next Day Service