Load Capacity

The main factors which determine the roller load capacity are the tube, shaft and bearing. The load capacity is dictated by the weakest of them:

1. Excessive load will distort the tube during roller operation which may result in permanent damage leading to unstable conveying of the product.
2. If the load capacity of the shaft is insufficient, it will change the adaptive capacity of the shaft and influence the running performance.
3. If the load exceeds the permitted load of the bearing, it will greatly reduce the bearing’s lifespan.

You need to know the following design information:

1. The rated load capacity of a single roller is the uniformly distributed load on the roller surface (not point load).
2. The method of mounting the shaft to the conveyor frame. For example, an internal threaded shaft has a higher load capacity than a loose mounted shaft such as a spring loaded shaft.
3. For each application, you need to consider how flat the product conveying surface is and any partial forces encountered during conveying.
4. Steel tube and stainless steel tube have similar mechanical properties with regards to load capacity so are typically considered to have same load capacity.
5. Increasing the thickness can strengthen the tube’s impact resistance (not easy to dent), but has little influence on the roller’s load capacity.
6. In some modes of conveying, especially in belt conveying, duty plays a decisive role rather than the load. The duty depends on the driving force such as belt maximum tension and chain tension.

Duty: Maximum loading of driven roller.

Load: Roller’s maximum weight capacity.