Hydraulic control valve is a general term for valves that use the principle of hydraulic control to achieve multi-purpose control through different structures. Hydraulic control valve is generally composed of main valve, pilot valve and other valves, control pipeline and so on. The hydraulic control valve uses the medium pressure of the pipeline itself as the power source to open, close and adjust. Different combinations of the pilot valve and the small pipeline of the system can have nearly 30 functions, which can be evolved into remote control according to the purpose, function and place of use. Floating ball valve, pressure reducing valve, slow closing check valve, flow control valve, pressure relief valve, hydraulic electric control valve, etc.