Because of the widespread use of hydraulic winch, gradually replaced the electric drive winch, reduce the electrical equipment electrical leakage caused by the electric winch. Hydraulic motor in the hydraulic winch can adjust the speed of mechanical operation, its in the process of lifting, the motor speed is low, when no load, the motor speed is high, it makes the choice of steel wire rope service life extension. The hydraulic winch develops rapidly, and the hydraulic and pressure transmission in its mechanism is widely used, replacing most mechanical structures.