Kunkle 171S

All 316 stainless steel non-code liquid relief valve — body, trim and spring — for corrosive service where a carbon steel or cast iron body will not survive. Kunkle notes the 171S is also suitable for sanitary applications depending on requirements; confirm your specific finish and cleaning requirements at quote. 1 to 400 psig and −20°F to 550°F, FNPT 1/2″ through 2″, relieving 1 to 374 GPM at 25% accumulation. Available with either a pressure-tight hood (catalog standard) or a packed lift lever for manual testing. Non-code: no ASME stamp, no National Board certification. Maximum back pressure 50 psig, increasing set pressure one-to-one and reducing capacity.