Hi all. I was wandering if anyone can explain or recommend a useful url regarding my question. I am tryingto find info on how jammed (seized) trough or return idlers affect the performance of the belt conveyor.
Idlers are to take care of required tension on slack side. If they are jammed, you will cough of some extra power because of friction and belt life can be lower.
The amount of drag a jammed return idler will cause will depend on the co-efficient of friction between the roller and belt and the weight/force of belt. This is going to vary greatly from belt to belt and due to roller spacing. There are also many factors which will effect the co-efficient of friction such as temperature, oil, dirt and speed.
Remember that the return rollers ride on the “top” of the belt so if you have a rough top “sticky” belt it can make a big difference. You should be able to get the co-efficient of friction from the belt mfg.
Possibly more important than friction is belt tracking. With non-rotating idlers there will be build-up on the roller. This will inevitably be non-uniform. Since a belt tends to align itself perpendicularly with a downstream pulley, accumulated material on the roller will cause the belt to track off.
From a non-engineer's standpoint, I can tell you that they add friction, increase amperage use, and eventually, the belt wears through them, causing sharp edges that tear up the conveyor belt. Jammed rollers are a belt distributor's best friend.