Devising a procedure for calculating the belt tension of a conveyor with a stopped drive when changing the transportation length

The object of this study is the working process of a belt conveyor. The task consideredrelates to designing belt conveyors taking into account the belt tension during a change in the transportation length. It was established that when the length of a non-working conveyor changes, the static and dynamic load of the belt increases. The change in the static load of the belt on the drum of the mobile station depends on the speed of the mobile station and the parameters of the conveyor. The dynamic load of the belt depends on the acceleration of the belt, which is associated with the acceleration of the mobile station during a change in the transportation length of the conveyor. The change in the load of the belt on the drum of the mobile station occurs in two phases: the first phase is the shift; the second phase is the acceleration and the change in the transportation length. The first phase lasts for several seconds, and the belt tension is equal to the resistance force of the empty conveyor line. The second phase lasts while the transportation length changes, and the belt tension depends on the parameters of the conveyor and the acceleration of the mobile station at this time. For a non-operating conveyor that changes the conveyor length, the static tension of the belt on the drum of the mobile station can increase by 2 times from the initial one. The dynamic loading of the belt can have a significant increase if the acceleration of the mobile station is not stretched in time and has large values. When operating the conveyor, it is necessary to change the transportation length when the conveyor is running. Using the Mathcad software, a stopped conveyor with a change in the transportation length was tested. Calculations showed that the belt tension was 10 % higher than for a conveyor with a running drive. The results make it possible to properly operate competitive machines equipped with a belt conveyor with a variable transportation length