Kunkle 6221 Safety Relief Valve — 3/4″ NPT, E Orifice (Steam ASME Section VIII, Teflon PFA Seat)
SKU: KUN-6221-ET-L-3_4
The Kunkle 6221 is an oversized-outlet, full-nozzle bronze safety relief valve with a Teflon (PFA) disc insert, for steam service only. This 3/4″ NPT inlet variant — E orifice, 0.216 in² — is available across a 3–250 PSI set pressure range for Steam ASME Section VIII service, carrying ASME Sections VIII and XIII (UV stamp), National Board Certified. The PFA disc provides tight, leak-free shutoff for steam applications. Body: bronze (BRZ B584-C84400); oversized side outlet (1-1/4″) with dual control rings for precise blowdown adjustment. Specify your required set pressure when requesting a quote.
Specifications
| Body Material | Bronze (BRZ B584-C84400) |
| Trim Material | Brass (BRS B283-C48500), Teflon (PFA) disc insert |
| Inlet Size | 3/4" NPT |
| Outlet Size | 1-1/4" NPT |
| Outlet Configuration | Oversized side outlet |
| Orifice Designation | E |
| Orifice Area | 0.216 in² |
| Set Pressure | 3–250 PSI |
| Temperature Range | Per PFA seat — contact for rating |
| Capacity — Steam VIII | 155–2829 |
| Flow Coefficient | 0.878 |
| Service Media | Steam |
| ASME Certification | ASME Sections VIII and XIII (UV stamp), National Board Certified |
| National Board Certified | Yes |
| Seat Type | Teflon (PFA) |
| Weight | 2-3/4 lb |
| Overall Height | 7-1/2 in |
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.
Get a Quote