Understanding Belt Troughing: Impact on Conveyor Performance and Maintenance
Belts are designed with a troughed shape to enhance their capacity for carrying materials. Increasing the trough angle allows the conveyor to accommodate a larger volume of material. Idlers play a crucial role in shaping flat rubber or PVC belts into troughs. The maximum trough angle is determined by factors such as the belt carcass type, belt thickness, width, and tension rating. Manufacturers typically specify troughability on technical data sheets, indicating the minimum belt width required for different trough angles.
Exceeding the maximum trough angle for a specific belt can cause permanent deformation, leading the belt to adopt a cupped shape. Cupping makes the belt challenging to seal, clean, and track properly. It reduces surface contact between the belt and the conveyor's rolling components, impairing the components' ability to steer the belt effectively.
When a belt's troughability limit is surpassed, it may fail to form the trough correctly, resulting in sealing and tracking issues. A belt that is too stiff to trough properly will also struggle to track correctly within the conveyor system. This misalignment can quickly escalate into material spillage from the conveyor's edges and damage to the belt's edges.
Additionally, exceeding the belt's troughing capability can damage the top and bottom covers as well as the carcass around the idler junctions. If the belt's troughability is not compatible with the troughing idlers, it may increase the power required to operate the conveyor beyond its original design specifications.