These valves are externally adjustable, and unlike shear relief valves, which use common nails to trigger the valve, Weir SPM's emergency relief valves utilize an internal spring, nitrogen, or rig air to activate opening and closing. Valves are available in 2",3" and 4" models. Operating pressures range from 1,000 psi to 20,000 psi. Standard service and sour gas models are available.
