Gas pressure reducing valve is a diaphragm-operated valve designed for chlorine, sulfur dioxide and ammonia gas service. It includes a pressure-reducing chamber for generating a gas pressure that acts on one surface of a diaphragm, a valve body that can sit on a valve seat having in its central part a valve hole communicating with the pressure-reducing chamber, and a spring biasing the diaphragm in a direction that detaches the valve body from the valve seat.

Gas pressure regulating valves are ideal valve for low-pressure gas regulation. The self-contained low-pressure gas regulator is for use on tank blanketing, gas meter inlet pressure regulating, gas burners and other low-pressure air and gas applications. It increases the outlet pressure are sensed through the aspirator causing the large elastomer diaphragm to rise, which moves the plug toward the seat. As outlet pressure decreases, the diaphragm moves down and moves the plug away from the seat to increase flow.