The pulley can be divided into two types: the drive pulley and bend roller. The function of the drive pulley is to move the conveyor belt by frictional drive between the cylinder surface and the belt surface while changing the direction of movement of the conveyor belt. Changing only the direction of movement of the conveyor belt without transmitting power is called a reversing drum (such as a tail drum, a vertical tension pulley, etc.). The drum is divided into a steel plate welding drum (large) and a casting drum (small).