Chemical pipe valve installation need to bypass valve

In chemical pipeline valve installation, the pipe valve and bypass valve has the need to install, can have what effect, for the many users are not often met, this also is not very understanding, actually set the bypass valve in the pipeline, its role, in general can be divided into two points: one is the protection, Balance the pressure on both ends) , 2 it is emergency! Protection: also can say to is a kind of main valve protection, prevent due to the large pressure difference before and after the valve, large in the resistance caused by open and not to open the valve, especially in some large diameter or high pressure pipeline. High pressure pipe through the bypass valve before opening pressure, in order to avoid high-pressure sudden rush, below the valve pipe forming. Or excessive pressure difference on both ends of the valve, open torque is too big, to avoid torsional damage the valve, and open after bypass pressure relief valves. Emergency function: used as standby line, the advantage is when the main valve malfunction, or need maintenance, can open the bypass valve flow, and shall not affect the normal production. Whether the valve to the specific requirements of the need to install the bypass valve and set: ( For reference only) 2. More than 5 mpa, DN400; 4. Level 0 mpa, DN250 above; 6. More than 4 mpa, DN200; More than 10 mpa, 6; DN100 ~ DN200 valves, the by-pass pipe and by-pass valve is 3/4 '; DN250 to 24 ') of the valve and the by-pass pipe and by-pass valve for DN25; DN600 above the valve and the by-pass pipe and by-pass valve DN40.