AC frequency control electric motor as power source, low speed high torque flexible drive, constant power output, energy-efficient, without noises and pollution.
Frequency control electric drive system consists of AC power source, AC frequency converter and AC electric motor. Power sources have three input powers: 75kW (40ton), 55kW (30ton), 37kW (20ton), they adapt to different oilfield transformer. Hook block speed is auto-adjusted according to different load, control system takes closed-loop design, and it can control electric motor’s rotating speed and torque exactly, low speed, good performance, output constant torque in the extreme low speed. Transducer can protect the electric motor in the condition of overloading, overheating and overcurrent. When there is no rotating speed, electric motor in the braking mode, it can keep the maximum torque, static hook load. Transducer makes the most of electric motor’s power, it has short period overloading capacity (1.5-2times); it can be started frequently or started steadily with negative load.
 
Main specifications:
Max. Load: 151875lbf (675kN)
Derrick height: 59ft (18m)
Hook blocks hoisting speed: 3.9ft/s (1.2m/s)

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