SKU: KUN-40R-1_2
The Kunkle 40R is an all stainless steel sentinel relief valve for non-code steam service on steam equipment, including steam turbines. IMPORTANT: sentinel valves are intended as audible warning devices, NOT for pressure relief. A 40R warns that a system has gone over pressure; it does not protect the equipment, and it must not be used in place of a code safety or relief valve. The 40R discharges from the top to give a visible warning of system overpressure. It uses a precision lapped beveled seat, and a pivot between the spring and disc corrects misalignment and compensates for spring side thrust. This 1/2″ male NPT variant is set between 1 and 400 psig (0.07 to 27.6 barg) over a temperature range of -60°F to 850°F (-51°C to 454°C). This is a non-code valve: it carries no ASME stamp and no National Board certification. Every valve is tested and inspected for pressure setting and leakage before shipping. Specify your required set pressure when requesting a quote – set pressures are ordered from 5 to 400 psig.
| Body Material | Stainless steel throughout – nozzle SA479-316, yoke and regulator ring A743-CF8 |
| Trim Material | Nozzle SA479-316; yoke, regulator ring and disc A743-CF8; lock screw ring SS 18-8; stem and spring steps A582-303; spring SA313-302 (302 SST); compression screw SA479-316; pressure screw A479-316; jam nut 18-8; hood aluminium SB85 A380.0; lift nut, hood set screw and drive screw A108 |
| Inlet Size | 1/2" male NPT |
| Outlet Configuration | Top discharge |
| Set Pressure | 1 to 400 PSIG (0.07 to 27.6 barg) |
| Temperature Range | -60°F to 850°F (-51°C to 454°C) |
| Service Media | Steam |
| ASME Certification | Non-code — no ASME stamp and no National Board certification. Sentinel (warning) service only, not a pressure relief device. |
| National Board Certified | No |
| Seat Type | Precision lapped beveled seat – A743-CF8 disc on SA479-316 stainless steel nozzle |
| Weight | 1 lb (0.45 kg) |
| Overall Height | 5.25 in (133 mm) |
Need a quote or have a technical question?
Call (324) 888-1524 or submit a quote request online. Requests received before 3 PM ET are typically quoted the same business day.
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