| problem |
cause |
action |
| Side wandering |
Pulleys idlers Not correctly adjusted ,contaminated or worn
Slide bars
Break points
Unequal temperature over the belt width |
Clean the items,make sure they are rotating freely,replace worn parts,adjust pulleys and idlers.
Ensure that a uniform temperature is achieved |
| Burrs at the edges |
Due to side wandering the belt has touched the structure or other rigid object. |
File the belt edges so that they are round.
Examine belt tracking. |
| Scratches on the load side |
Feeding and/or discharge or other parts in contact with the belt are damaged |
Repair or replace the damaged parts |
| Scratches on the running side |
Belt support,safety scraper or other parts in contact with the belt are damaged |
Worn or damaged parts need replacing.
For adjustment of idler sets. |
| Wavy edges |
Due to side wandering the belt has touched the structure or other rigid object.
Pressure of belt edges than at the middle lf the belt. |
The damaged edge must be cut lf and the new edge carefully filed round.
The conditions causing the damage must be corrected. |
| Wavy edges and/or small blisters in the belt |
Uneven temperature |
Usually these deformations disappear at ambient or uniform temperature.
In cases where the deformations remain in the belt. |
| Deformations 2235.31 2385.14 2248.85 |
Pulleys contaminated.
Belt support contaminated and/or damaged.
Belt tension too high |
Clean pulleys
Clean or replace belt support
Check scrapers,rollers in contact with the belt surface.
Note:
Belts with concave or convex deformations can be levellde by special leveling devices.Please contact your nearest Sandvik office. |
| Loose rivets in the joint |
Normal wear,or feeding and/or discharge device incorrect |
Loose rivets must be drilled ort and replaced by new ones.If necessary,the whole joint must be cut out and a new joint made. |
| Hairline cracks in welded joint |
Normal wear |
Contact our office regarding repair welding |
| Hairline cracks |
Fatigue of the belt |
If the crack is at the belt edge,a crescent-shaped piece may be cut out and the edges filed round.
If the crack is not at the belt edge,small holes may be drilled at each end of the crack to prevent it spreading.
Thoroughly remove burrs at the drill holes. If the crack develops from the belt edge,and is so long that the belt edge cannot be cut,a smail hole should be drilled at the end of the crack.
Fatigue cracks can also be welded,for further information.
When a belt shows signs of fatigue,the purchase of a spare belt should be considered. |
| Accidental damage |
|
It may be mecessary to cut out the damaged section and to splice in a new piece.
Note:
The length of the new section must not be less than 2/3 of the circumference of the pulley. |
| Incorrect belt tension |
Temperature variarions.Tension device does not operate properly. |
The specific tension stress is 10 N/mm2 of belt crossectional area with plain belts and 7 N/mm2with true-tracking belts.
Check whether the tension is correct by measuring the sag of the belt between two idlers in the bottom srtand.See part 1,page 8,figure 8.Adjust take-up bearings.Check tension device,counterweight or tension springs. |
| V-ropes or true-tracking belts worn or loose |
V-rope sheaves not correctly adjusted.
Accident. |
Adjust sheaves.Prevent accidents.If a new section of V-rope needs fixing. |
