For the hoisting mechanism of the electric bridge crane trolley, a double band brake with a long stroke electromagnet and closed by heavy weight was selected and tested. The crane has a lifting capacity of 10 tons and works as an intermediate job type. The current is alternating current. Pulley group-twin type, the magnification is two. The gear ratio of the reducer is 62, the efficiency of the mechanism is 0.92, and the diameter of the reel is 500cm.
It is determined according to the braking torque formula of the bridge crane, where the braking safety factor is 2, which is suitable for intermediate work types. The cargo torque converted to the brake shaft is equal to 1860 kg, so the braking torque should be equal to two 1860, which is 3720.
The brake with electromagnet is selected according to the standard of bridge crane. The most suitable braking torque is the brake wheel size and electromagnet.
