One application in the natural gas industry is the use of full-port ball valves under safety relief valves (SRV). Full-port must be used because pressure or flow restrictions directly under SRV’s can cause performance problems and violate ASME code guidelines. Good engineering practice further tells us inlet risers to the SRV must be kept as short as possible for reasons of thrust and allowing technicians to perform yearly testing at ground level. Pilot operated srv’s have an option called a “Field Test Connection” (FTC). FTC’s only verify that the pilot is functional but do not move or cycle the piston inside the main valve. A-T has the solution by allowing technicians to put test gas to the entire spring or pilot operated SRV.

A-T’s Series WB and TS3 (with special flange test port) ball valves shall be counted as the best and most complete SRV testing solution available. For small SRV installations the WB series is an excellent choice for NPT connections. The Series TS3 trunnion is the answer for larger SRV’s with flange connections. Request the flange test port modification that shall be installed closest to the SRV. The use of regular port ball valves, spool’s, and bleed rings are old technology and should be changed.

-Review by Gary Beckett, RM Headlee
SRV Block Test Paper from RM Headlee