Hydraulic control valve consists of a main valve and attached to the catheter, pilot valves, needle valves, ball valves and pressure gauges and other components. Depending on the purpose, function and different places can be turned into floating remote control valve, relief valve, slow closing check valve, flow control valves, pressure relief valves, hydraulic electric control valves, pumps and control valves. Hydraulic control valves to be installed before the filter, and should be easy sewage requirements. Hydraulic control valve is a medium pressure pipe for power, were open and close, regulating valves. It consists of a main valve and attached to the catheter, needle valve, ball valves and pressure gauges and other components, according to the purpose of use, places of different functions can be turned into a floating remote control valve, relief valve, slow closing check valve, flow controller , pressure relief valve, hydraulic electric control valves, emergency shut-off valve. Pilot valve varies with the medium level and pressure operates, since many types of pilot valve, may be used alone or several in combination, can be obtained on the main valve and the water pressure and flow regulation individually and composite functions .