Kunkle 267P Relief Valve — 0.110 in² Orifice, Steam ASME Section VIII

The Kunkle 267P is an extra heavy relief valve for the protection of pumps, compressors, pressure vessels and systems handling corrosive fluids or vapors at high pressure and temperature. It is also suitable for sentinel (warning) service on steam equipment. The 267 is the Model 266 with a high-temperature tungsten alloy spring. Construction is all 316 stainless steel – SS A351-CF8M housing and bonnet, with a top guided design, seats lapped to optical flatness and a ball pivot between disc and spring that corrects misalignment and compensates for spring side thrust. It is supplied as the 267P with a pressure-tight packed lift lever, which ASME requires for steam code service. This variant is configured for Steam ASME Section VIII service with a 0.110 in² (0.710 cm²) orifice, relieving 79 to 10,036 lb/h (4 to 2,000 psig) over a set pressure range of 4 to 2,000 PSIG (0.28 to 137.9 barg). Temperature range is -320°F to 750°F (-195°C to 399°C). Code service applies at set pressures of 15 psig and above; below 15 psig the valve is supplied non-code and carries no ASME stamp. IMPORTANT: the full pressure rating applies to FEMALE NPT inlets. Male NPT inlets derate with size and temperature – a 1/2″ male inlet is limited to 1,950 psig at 100°F and 1,055 psig at 750°F, and a 3/4″ male inlet to 1,770 psig at 750°F. Specify your inlet size, inlet type and service temperature when requesting a quote. Maximum back pressure is 400 psig (27.6 barg); back pressure raises the set pressure on a one-to-one basis and reduces capacity, and back pressure above 10% of set pressure is not recommended. Due to the capacity of these valves, thrust calculations should be reviewed and the valve supported accordingly. Inlet sizes 1/2″, 3/4″ and 1″, NPT or BSPT, male or female – specify when requesting a quote.

↓ Kunkle 264/265/266/267 Datasheet (PDF)