Knowledge of the relief valve

Relief valve knowledge first, the principle and structure of the relief valve type relief valve is a kind of automatic cut pipe special device, the stress of work, it can be by high water pressure reducing valve before the pipe to the valve pipe after the required level. Pressure relief valve is widely used in high-rise buildings, the area of urban water supply pipe network pressure is too high, mines and other occasions, to ensure the water supply system in the water points to obtain the appropriate service water pressure and flow rate. In view of water leak rate and degree of waste almost as the water pressure is directly proportional to the size of feed water system, so the relief valve have improve system operation condition and potential water-saving effect, according to statistics the water-saving effect is about 30%. A lot of structure type and pressure relief valve, common in the past have a spring in the diaphragm, piston, etc. Within the basic principle is to rely on the valve and pressure relief valve port on the local resistance to reduce the water pressure, water pressure drop range by the connection of valve disc film or the import and export pressure difference on both sides of the piston automatic adjustment. In recent years appeared some new type pressure relief valve, such as constant ratio and pressure relief valve. Constant ratio reduced pressure principle is to use the floating piston in the hydraulic valve body ratio control, import and export side pressure ratio is inversely proportional to the import and export side piston area ratio. The relief valve working smoothly without vibration; The valve body without spring, so no spring rust, metal fatigue failure were evident; Good sealing performance, leakage and dynamic pressure reduction (both The water flow) And static pressure reduction ( When traffic is 0) ; Especially in relief at the same time does not affect the water flow. 5 mpa, regulating range error is & plusmn; 5% ~ 10%. It should be noted that the head loss of water flow through the relief valve is very big, but due to reduced water waste and make the system layout and reasonable flow rate distribution and improve the system condition, so the overall is still the energy saving. Second, the basic performance of pressure relief valve ( 1) Regulating range: it refers to the pressure relief valve output pressure P2 adjustable range, meet the precision within the scope of this requirement. Regulating scope mainly related to pressure regulating spring stiffness. ( 2) Pressure feature: it refers to the flow fixed value for g, caused by the input pressure fluctuation characteristics of the output pressure fluctuations. The smaller the output pressure fluctuation, the characteristics of pressure relief valve, the better. The output pressure must be less than the input pressure & ndash; Constant value was basically not changes over the input pressure. ( 3) Flow feature: it refers to the input pressure & ndash; Timing, the output pressure changes along with the change of output flow g resistance. G when the flow changes, the output pressure changes as small as possible. Generally the lower the output pressure, which fluctuates according to the change of output flow. Third, the selection of pressure relief valve in accordance with the requirements of using the selected decompression valve type and voltage regulation accuracy, then choose the size according to the maximum output flow required. 1 mpa. Relief valve is generally installed in the water gas filter, oil mist device or setter, and pay attention to answer against its import and export; Valve need not when should the knob is loosened, lest often compression deformation of diaphragm and affect its performance.