ASME Specified

• Protect fired and unfired hot water vessels against overpressure conditions Feature a unique fail safe disc

Bell & Gossett cast iron ASME safety relief valve Model 4100 is designed to protect fired and unfired hot water vessels against overpressure conditions. Bell & Gossett diaphragm operated cast iron ASME safety relief valves are engineered in accordance with the requirements of section IV of the ASME boiler and pressure vessel code for heating boilers and their capacities are certified by the national board of boiler and pressure vessel inspectors. The effective area of the EPDM diaphragm is approximately 5X greater than some conventional "pop-type" relief valves. The diaphragms "oversized" effective area generates a greater operating force which helps to overcome the effects of fouling. Bell & Gossett ASME safety relief valves feature a unique fail safe disc with sufficient area to permit the valves to maintain their safety relief function in the event of a diaphragm rupture. The low differential between opening and closing pressures prevent conditions under which system water might flash into steam and cause hammering. Under normal operating conditions thermal expansion opens the valve allowing water to discharge at a low rate of flow. Under emergency conditions the valve will discharge its certified capacity. Bell & Gossett iron body ASME safety relief valves are available in a wide range of pressure settings, to closely match the Btu/hr output rating of hot water heating boilers and the Btu/hr load of heat exchangers and other pressure vessels handling water at a maximum pressure of 125 psi (8.6 bar) and maximum temperature of 250 deg F (121 deg C).