The Valve,safety Relief, cataloged under National Stock Number 4820-00-349-8951, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 26 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-349-8951 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPETPOPPET |
| Nominal Pipe Size Accommodated | 1.500 INCHES FIRST END1.500 INCHES FIRST END IN |
| Nominal Pipe Size Accommodated | 1.500 INCHES SECOND END1.500 INCHES SECOND END IN |
| Connection Style | PLAIN,OPTIONAL END(PIPE) FIRST ENDPLAIN,OPTIONAL END(PIPE) FIRST END |
| Connection Style | PLAIN (PIPE) SECOND ENDPLAIN (PIPE) SECOND END |
| Connection Type | THREADED EXTERNAL PIPE SECOND ENDTHREADED EXTERNAL PIPE SECOND END |
| Connection Type | THREADED INTERNAL PIPE FIRST ENDTHREADED INTERNAL PIPE FIRST END |
| Style Designator | ANGLE |
| Operating Pressure | 250.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +2.0 TO 250.0 POUNDS PER SQUARE INCH+2.0 TO 250.0 POUNDS PER SQUARE INCH LBS |
| Thread Direction | RIGHT-HAND SECOND ENDRIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST ENDRIGHT-HAND FIRST END |
| Nominal Thread Size | 1.500 INCHES FIRST END1.500 INCHES FIRST END IN |
| Nominal Thread Size | 1.500 INCHES SECOND END1.500 INCHES SECOND END IN |
| Maximum Operating Temp | 450.0 FAHRENHEIT SINGLE RESPONSE450.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Media for Which Designed | STEAM SECOND RESPONSE |
| Media for Which Designed | STEAM SECOND RESPONSEAIR FIRST RESPONSE |
| Thread Quantity Per Inch | 11-1/2 FIRST END11-1/2 FIRST END |
| Thread Quantity Per Inch | 11-1/2 SECOND END11-1/2 SECOND END |
| Material | STEEL STEM |
| Material | COPPER ALLOY SEATCOPPER ALLOY BODY |
| Material | STEEL STEMCOPPER ALLOY SEAT |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | NPT SECOND ENDNPT FIRST END |
| Opening Pressure Setting | 50.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATICAUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 4712N15-1 1-2 50PSI | 3/9 Design control — primary reference Mcmaster-Carr Supply Co |
NSN 4820-00-349-8951 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-349-8951: Flow Control Device: POPPETPOPPET; Nominal Pipe Size Accommodated: 1.500 INCHES FIRST END1.500 INCHES FIRST END IN; Nominal Pipe Size Accommodated: 1.500 INCHES SECOND END1.500 INCHES SECOND END IN; Connection Style: PLAIN,OPTIONAL END(PIPE) FIRST ENDPLAIN,OPTIONAL END(PIPE) FIRST END. 26 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.