Pouch conveyor drive system dynamics

Pouch conveyors commonly employ point-contact drive systems, indenting a rigid drive wheel into the viscoelastic running surface of the conveyor. Rigid indentation of a viscoelastic surface exhibits regions of stick and slip, reducing the tractive limits of the contact. By modelling the conveyor cover as both an elastic material, and using a 3-parameter Maxwell approximation, a comparison can be made to predict the attainable traction of both indentation and load dependent contacts, highlighting the influence of viscoelasticity in the drive contact. Accurate prediction of the slip within the contact region allows appropriate drive placement and spacing along a conveyor, maximising transmission of drive power and efficiency, while minimising capital/operating cost and surface wear. Experimental results are presented to validate the model, using both polished steel and wheels with polyurethane, ceramic and rubber lagging.