Security function and working principle of pneumatic valve

security pneumatic valve in the system of security protection. E. , when the system pressure exceeds safety pneumatic valve open, statins are part of the gas system to the atmosphere, make the system pressure shall not exceed the allowable values, thus ensuring the system is not an accident because the pressure was too high. Safety pneumatic valve is also called the overflow valve. Graphic form for safety several typical structures of pneumatic valve. The figure for a pneumatic piston type safety valve, pneumatic valve core is a tablet. Air pressure in A piston, when pressure exceeds set by spring force TVC, the piston is A top drive, part of the compressed air from the pneumatic valve mouth namely atmosphere; When air pressure is lower than the TVC, spring driving the piston down, close the pneumatic valve.

figure b and c respectively, pneumatic ball valve type pneumatic valve diaphragm type safety, working principle and the piston is exactly the same. These three pneumatic valve is spring safety control, adjust the spring pre-tightening force, can change some size, so called direct acting safety pneumatic valve.


figure d pneumatic for pilot operated safety valves, to provide control small straight moving pneumatic valve pressure acting on the diaphragm, diaphragm on hard core is pneumatic valve core, pressure in the pneumatic seat. When air pressure is greater than A security, pneumatic valve core is open, the compressed air output from the left side of the hole into the atmosphere. Pneumatic diaphragm type safety valves and pilot operated safety characteristics better, pneumatic valve pressure; But the biggest open force is small, the poor flow characteristic. Practical application, should according to the actual need to choose the type of security pneumatic valve, and choose the size according to maximum displacement.