Hydraulic control valve classification, characteristics, maintenance and repair

Hydraulic control valve is a water pressure control valve, which consists of a main valve and attached to the catheter guide valve needle valve and pressure gauges and other components. According to the purpose of use? Function and place can be evolved into a remote control float valve? Pressure relief valve? Slow closing check valve? Flow control valve? Relief valve? Hydraulic electric control valve, pump control valve. Hydraulic control valve according to the structure can be divided into two types of diaphragm and piston, the same working principle, are the pressure difference above and downstream △ P as the power, pilot controlled by the diaphragm (piston) hydraulic differential operation, completely by the hydraulic Automatic adjustment, so that the main valve disc fully open or fully closed or in regulation. When the pressure water entering the control chamber above the diaphragm (piston) is vented to the atmosphere or downstream low pressure zone, the pressure acting on the bottom of the valve disk and under the diaphragm is greater than the pressure above, pushing the main valve disk fully open (Piston) above the control chamber pressure water can not be discharged to the atmosphere or the lower reaches of the lower pressure zone, the role of pressure on the diaphragm (piston) is greater than the pressure value below, it will be the main valve disc Pressure to the fully closed position; when the pressure value in the control chamber above the diaphragm (piston) is between the inlet pressure and the outlet pressure, the main valve disc is in an adjusted condition, the adjustment of which depends on the needle valve and the adjustable Pilot valve joint control. Adjustable pilot valve through the downstream outlet pressure and with its changes to open or close its own small valve port, thereby changing the diaphragm (piston) above the control room pressure value, control valve plate valve position adjustment. Hydraulic control valve repair and maintenance Hydraulic control valve is a self-lubricating water valve body, without additional oil lubrication, in case of damage to the main valve components, according to the following instructions for disassembly. (Note: The general consumption of damage within the valve products for the diaphragm and ○ ring, other internal parts little damage) 1. The main valve before and after the end gate valve closed. 2. Release the pipe fitting screw on the main valve cover to release the pressure in the valve. 3. Remove all screws, including the nuts of the necessary brass in the control line. 4. Take the valve cover and spring. 5. The axis, diaphragm, piston and other removed, do not damage the diaphragm. 6. After the above items are removed, check the diaphragm and ○ ring is damaged; if no damage do not subcontract their own internal components. 7. If it is found that the diaphragm or o-ring is damaged, please loosen the nut on the shaft core, break out the diaphragm or ring by Zhejiang, and then replace it with a new diaphragm or o-ring. 8. A detailed examination of the main valve internal valve seat, shaft and other damage if any other debris in the main valve to clean it out. 9. In reverse order is the replacement of the main components of the valve assembly, pay attention to the phenomenon of the valve can not be jammed.