General safety pneumatic valve and pilot operated safety what is the difference between the working medium of pneumatic valve? Suitable for medium pilot operated safety pneumatic valve?

general safety pneumatic valve and pilot operated safety what is the difference between the working medium of pneumatic valve?
general security pneumatic valve is called spring loaded safety valves, relying on the preset spring pressure pressure pneumatic valve core, ACTS on the sealing surface sealing, beyond the pressure of the spring, when the work abnormal pressure pneumatic valve core movement, the pressure release. Pilot operated pressure pneumatic valve, pneumatic valve above the catheter guided ventilation pressure before and after the valve core, make the balance, when the front pressure is greater than the back pressure pneumatic valve core, the conduction of stress wave, will control chamber of piston top to former channel, pneumatic valve after pressure is less than before the pneumatic valve, pneumatic valve core movement, the leakage of water hammer wave, protect the security of the pipeline, the side pressure below normal, protect the piston seat back, will pressure before and after the conduction of balance, reply to protect normal pneumatic valve, protection value by working chamber top wire adjustment.
what medium pilot operated safety pneumatic valve is suitable for use?
used in the gas industry is more, long distance pipeline of natural gas industry and distribution station, city gate station with more, almost all use, mainly because the guide type safety sensitive pneumatic valve and discharge ability to use it.