Straightening roll life-time

The dynamic load capacity of a straightening roll depends on its material fatigue characteristics and wear. Useful life depends on the straightening roll's loading, speed, conditions of lubrication, soiling, installation and temperature, the statistical probability of the first incidence of damage, and diverse other factors. All too often the impact of dirt is underestimated.

The load capacity and useful life of straightening rolls from Witels are determined by the methods customary in rolling bearing practice. At the same time allowance is made for the fact that the outer ring undergoes elastic deformation through contact with the product to be straightened. Compared to a rolling bearing supported in a housing bore, there is a different distribution of load in the bearing and bending stress in the outer ring. We differentiate between internal and external factors with an influence on wear.

Contact between the product to be straightened and the outer ring results in the following external factors:

1. material of the outer ring
2. material and surface consistency of the product to be straightened
3. speed
4. slip
5. soiling and lubrication

Internal factors with an influence on straightening roll wear are:

1. lubrication of the bearing
2. type of bearing
3. dynamic and static bearing load
4. speed
5. seal arrangement
6. elastic deformation