Reasons for insufficient traction force:
A. The groove is worn or the diameter of the traction rope is reduced. Because the frictional force is not a constant during the entire life of the elevator. As the rope groove wears and the diameter of the rope continues to decrease, the traction rope gradually approaches the bottom of the groove so that the clamping force of the tangent point between the rope and the rope groove (for the V-shaped rope groove) also gradually decreases, resulting in friction insufficient;
B. The pitch diameter of the traction wheel varies. During the ascent of the car, the traction rope wound on the wheel groove with a larger pitch circle diameter has a greater circumferential speed than the traction rope wound on the wheel groove with a smaller pitch circle diameter, which causes an increase in the pulling force. The tension of each traction rope is uneven, resulting in a different contact pressure between the traction rope and the wheel groove, that is, the tension ratio of each traction rope is too large, and the sliding amount of the traction rope also increases;
C. The wrap angle of the traction rope on the rope groove of the traction sheave is smaller than the design requirements;
D. The reprocessing of the newly replaced traction rope and traction rope groove is inconsistent with the original design.
4. The balance coefficient does not meet the requirements of the standard Gb10058: the balance coefficient of various elevators is 40%~50%. That is, when the elevator is lifting, the counterweight and the car should work in a balanced state as much as possible, otherwise the load of the motor will increase, and the motor coil will be heated and damaged, and it will also affect the leveling of the car or the safety performance of the operation. As we all know, the traction rope of the elevator must be larger than the difference between the load of the car and the counterweight side to make the elevator operate normally.
