FISHER-67CS, 67CSR, 67CFS, 67CFSR-Pressure Regulator Valve
Internal Relief (Types 67CR, 67CSR, 67CFR and 67CFSR) If for some reason, outside of normal operating conditions, the downstream pressure exceeds the setpoint of the regulator, the force created by the downstream pressure will lift the diaphragm until the diaphragm is lifted off