The winch used for Wireline Unit is skid-mounted, which is mainly for convenient hoisting and transportation, occupying land, and the skid-mounted wire winch is generally divided into two parts: the power part and the winch part. The power part is composed of a diesel engine (electric motor) and a hydraulic oil pump. The diesel engine (electric motor) drives the hydraulic oil pump to transport the power fluid to the winch through a high-pressure hose. The winch is mainly composed of hydraulic motor, transmission mechanism, control mechanism, depth counting system and wire drum.