The advantages and disadvantages of different valves and their respective applicable occasions

Classified by purpose and function The cut-off valve is mainly used to cut off or connect the medium flow. Including gate valves, globe valves, diaphragm valves, ball valves, plug valves, butterfly valves, plunger valves, ball plug valves, needle-type instrument valves, etc. Regulating valves are mainly used to adjust the flow and pressure of the medium. Including regulating valve, throttle valve, pressure reducing valve, etc. Check valves are used to prevent the medium from flowing back. Including various structures classified by purpose and function. The cut-off valve is mainly used to cut off or connect the medium flow. Including gate valves, globe valves, diaphragm valves, ball valves, plug valves, butterfly valves, plunger valves, ball plug valves, needle-type instrument valves, etc. Regulating valves are mainly used to adjust the flow and pressure of the medium. Including regulating valve, throttle valve, pressure reducing valve, etc. Check valves are used to prevent the medium from flowing back. Includes check valves of various structures. Shunt valves are used to separate, distribute or mix media. Including various structures of distribution valves and traps, etc. Safety valves are used for safety protection when the medium is overpressured. Including various types of safety valves. Classification by main parameters (1) Classification by pressure Vacuum valves whose working pressure is lower than the standard atmospheric pressure. Low pressure valve is a valve whose nominal pressure PN is less than 1.6MPa. The nominal pressure of the medium pressure valve is PN2.5~6.4MPa. The high pressure valve has a nominal pressure of PN10.0~80.0MPa. Ultra-high pressure valve is a valve whose nominal pressure PN is greater than 100MPa. (2) According to the temperature of the medium, the high temperature valve t is greater than 450C. The medium temperature valve 120C is smaller than the valve whose t is smaller than 450C. Normal temperature valve -40C is less than t less than 120C. Low temperature valve -100C is less than t is less than -40C. The ultra-low temperature valve t is less than -100C. (3) Classification by valve body materials Non-metallic materials valves: such as ceramic valves, glass fiber reinforced plastic valves, and plastic valves. Metal material valves: such as copper alloy valves, aluminum alloy valves, lead alloy valves, titanium alloy valves, Monel alloy valves, cast iron valves, carbon steel valves, cast steel valves, low alloy steel valves, high alloy steel valves. Metal valve body lining valves: such as lead-lined valves, plastic-lined valves, and enamel-lined valves. General classification method This classification method is divided according to principle, function and structure. It is currently the most commonly used international and domestic classification method. General gate valve, globe valve, throttle valve, instrument valve, plunger valve, diaphragm valve, plug valve, ball valve, butterfly valve, check valve, pressure reducing valve, safety valve, trap, regulating valve, foot valve, filter , Blowdown valve, etc.