Kunkle 71S Liquid Relief Valve — 2″ FNPT (Cast Iron, Non-Code Liquid)

Photo shows the carbon steel Model 171. The 71S is the same design with a cast iron body.

The Kunkle 71S is a cast iron non-code liquid relief valve for overpressure relief, pressure regulation, by-pass relief and the protection of pumps, tanks, lines and hydraulic systems carrying acid, caustic, ammonia and other corrosive liquids. This 2″ FNPT variant relieves 19 to 296 GPM across a 1–250 PSI set pressure range at 25% accumulation. Construction is a cast iron (A126) body with a lapped stainless steel seat and disc (A743-CF8M), an A351-CF8M stainless nozzle and a 316 stainless spring; temperature range -20°F to 406°F. These are NON-CODE valves: no ASME stamp and no National Board certification. Maximum back pressure is 50 psig — back pressure increases set pressure on a one-to-one basis and reduces capacity. Capacities shown are at 25% accumulation; multiply by 0.9, 0.8 or 0.6 for 20%, 15% or 10%. Set pressures are ordered from 5 to 250 psig. Specify your required set pressure when requesting a quote.

↓ Kunkle 71S/171/171P/171S Datasheet (PDF)