The Complete Guide to Chain

2.3.3 Wear Between Rollers and Bushings

During the operation of conveyor chains, rollers receive some additional forces, which are shown in Figure 2.23 and listed below:

  1. The weight of conveyed objects when they are put directly on the chain.
  2. The reaction forces when pushing conveyed objects with a dog.
  3. Directional variation tension when the rail is set in a curved path.

These forces cause wear between rollers and bushings.

Some manufacturers publish an "allowable roller load"—a value at which the wear rate of the roller is comparatively slow. For steel rollers, it is the value with lubrication. For engineered plastic rollers and bearing rollers, the values shown are without lubrication. Sometimes, engineered plastic rollers may be affected by speed. Please check the catalogs.

If foreign objects, including conveyed objects, get into the working parts of the chain, the catalog values are no longer applicable, even if you are using lubrication.

There are many conveyed objects that work as lubricants; therefore, it is hard to generalize about the allowable roller loads when there are any foreign objects that might get into the working parts. Furthermore, the loads on the rollers (as shown in points 1 through 3 above), are also applicable to the side rollers and to the resulting wear of pins and side rollers. Make sure you consider these factors when setting up a conveyor system.

Figure 2.23 Forces on Conveyor Rollers
Figure 2.23 Forces on Conveyor Rollers