Gas or fluid pipeline safety valve - has plug with annular elastic body supported on inside of control chamber

摘要

The safety stop valve is for pipes handling gas or fluid, the shut-off mechanism reacting to the pressure drop across it and having an auxiliary mechanism acting on the plug, controlled dependent on the volume of part of the medium passing through. This part flows via a branch passage into a control chamber, where it acts on a diaphragm. The latter divides the chamber into an intermediate one connected via the shut-off mechanism to the discharge, and a pressure chamber connected to the branch passage. The diaphragm has on the side towards the shut-off mechanism a control member bringing the latter into the shut position when a predetermined volume has flowed into the pressure chamber, and its inherent stiffness returns it to the starting position.