The valve type

Valve is the control unit in fluid conveying system, has the truncation, regulation, guide, to prevent the reverse flow, voltage regulator, the leakage of the shunt or overflow, and other functions. Many different kinds of valves, and there are many classification methods: one, according to the purpose and function classification 1, block valves: mainly used for truncated or through media stream. Include gate valves, globe valves, diaphragm valves, plug valves, ball valves, butterfly valves, etc. 2, the regulator class: it is mainly used for regulating the flow of medium, pressure, etc. Including the regulating valve, throttle valve, relief valve, etc. 3, the check valve class: medium is used to prevent backflow. Including all kinds of structure of check valve. 4, the diverter valve class: for distribution, separation or mixed media. Including all kinds of structure of distributing valve and steam trap. 5, the relief valve: used for overpressure protection. Including all types of safety valve. Second, the main parameters according to the classification, according to the stress classification (1 1) Vacuum valve working pressure is lower than the standard atmospheric pressure of the valve. ( 2) Low pressure valve nominal pressure PN< 1. 6 mpa. ( 3) Medium pressure valve nominal pressure PN< 2. 5 ~ 6. 4 mpa. ( 4) High pressure valve nominal pressure PN10. 0 ~ 80. 0 mpa. ( 5) Ultrahigh pressure valve nominal pressure PN≥ The valve of 100 mpa. 2, according to the work of medium temperature classification ( 1) High temperature valve t> The valve of 450 ℃. ( 2) Medium temperature 120 ℃ & le valve; t< The valve of 450 ℃. ( 3) The normal temperature valve - 40℃≤ t< The valve of 120 ℃. ( 4) Cryogenic valve - 100℃≤ t< - - - - - - The valve of 40 ℃. ( 5) Cryogenic valve t< - - - - - - The valve of 100 ℃. 3, according to the valve body material classification, 1) Non-metallic materials such as ceramics, plastics, glass fiber reinforced plastic valve valve valve. Shaanxi valve ( 2) Metal materials such as copper alloy valve, aluminum alloy, lead alloy, titanium alloy valve valve valve iron, carbon steel, low alloy steel valve valve valve, high alloy steel valves. ( 3) Metal body lining such as lead lined valves, valve lining plastic valves, valve lining enamel. Three, general classification of this kind of classification method according to the principle, function and the division of the structure, is the current domestic and international the most commonly used classification method. Generally divided into: gate valve, globe valve, plug valve, ball valve, butterfly valve, diaphragm valve, check valve, throttle valve, safety valve, relief valve, steam trap, the regulator.