Causes
- Coefficient of friction too low
- Oil or other media wetting surface
- Very high belt tension
Effects
- Slipping of the belt
- Differential speed from belt to roll
- Rapid coating wear
- Uncontrolled belt movement
S-rolls are used to control tension. This requires a very high coefficient of friction in order to be able to transfer large torques between the roller and the belt. S-rollers usually have a wrap angle >180°.
In contrast to the S-rolls, drive and brake rolls only have contact with the belt in a narrow nip.
Slipping of roll covers causes increased wear due to abrasion on the coatings. This can lead to slippage of the strip or also interfere with the control of the drives.
