What is the difference between a safety valve and a relief valve?
Control Devices offers two standard types of pressure relief devices for air. A safety relief valve, or pop-off valve, is set to a predetermined pressure using a spring force to counteract the air pressure force. When the force created from the air pressure becomes greater than the spring force, the valve pops fully open and vents air to the atmosphere. Safety relief valves are sized in such a manner that the valve will always have a greater flow capacity than the source creating the air pressure (i.e. an air compressor). The valve will remain open until a reseat pressure is reached. This reseat pressure varies with valve type and is usually between 35% to 75% of the set pressure. Control Devices has eight series of valves that are manufactured in accordance with Section VIII of the ASME Boiler and Pressure Vessel Code. We also manufacture a wide range of non-code valves. See our Products section for information on the valve types. A relief valve is set to a predetermined pressure with
