Because the hydraulic coupling solves the difficult problem of motor starting, so the motor start with heavy load approximate load, and low starting current, short starting time, small impact on the grid, the startup process of low power consumption; the startup time is longer, the number of starts more frequently, using more energy saving hydraulic coupling transmission. Reducing motor capacity and energy saving Because the hydraulic coupler can solve the problem of difficult mechanical startup of large inertia, plus overload protection, isolation impact and vibration torsion, when designing and selecting, there is no need to increase the selection margin of motor greatly, usually press the type selection. PZ;; PB; Pd =I: I.05: 1.1 PZ - working shaft power. Kw PZ - coupler rated power kw Pd - motor rated power, kw The hydraulic coupling drive and rigid transmission ratio can at least reduce one motor seat number, reduce installed capacity 15% ~ 25%.d, and reduce the motor sea