Classification and characteristics of hydraulic control valves
????Hydraulic control valve according to the structure can be divided into two types of diaphragm and piston type, the same works are more than the downstream pressure difference △ P is the power, the pilot valve is controlled by the diaphragm (piston) hydraulic differential operation entirely by water automatically adjusted, so that the main valve disc is fully open or fully closed or is in regulation. When entering the separator (piston) above the control pressure chamber is discharged to the atmosphere or the water downstream of the low pressure area, and the effect of pressure beneath the diaphragm on the bottom of the valve disc is greater than the upper pressure value, the main valve will fully open the valve disc onto the position; when entering the separator (piston) above the control chamber pressure of the water is not discharged to the atmosphere or a low pressure area downstream of the role of the membrane (piston) is greater than a pressure value above the pressure below the main valve so that the valve disc will down to the fully closed position; when the diaphragm (piston) above the control chamber pressure is intermediate the inlet pressure and the outlet pressure, the main valve disc is in regulation, for adjusting the position of the conduit system depends on an adjustable needle valve and joint control action pilot valve. Adjustable pilot valve can change and with it the pressure downstream of the outlet opening by large or small off its own small valve port, thereby changing the diaphragm (piston) pressure above the control room, the control valve to adjust the position of party disk.
????Selection and precautions hydraulic control valve
Use hydraulic control valve, first thing to note selection. Improper selection can cause water resistance and air leaks. Optional hydraulic control valve, the device must be multiplied by the hourly steam consumption for the largest selection of magnification condensation of water 2-3 times to select the hydraulic control valve displacement. To ensure the hydraulic control valve in the car as soon as condensate can be discharged rapidly increase the temperature of the heating equipment. Hydraulic control valve discharge energy is not enough, will cause condensation of water can not be discharged, reduced thermal efficiency of heating equipment.
Optional hydraulic control valve, you can not choose to nominal pressure hydraulic control valve, because only nominal pressure hydraulic control valve, said shell to withstand pressure levels, very different hydraulic control valve nominal pressure and working pressure. So you want to select a displacement of the hydraulic control valve according to the working pressure. Working pressure is the pressure of the hydraulic control valve before work minus the hydraulic control valve outlet back pressure difference. Select the required hydraulic control valve accurately waste gas drainage, high sensitivity, can improve the utilization of steam, the steam does not leak, reliable performance, easy high back pressure, long life, maintenance is the preferred conditions.