The Valve,safety Relief, cataloged under National Stock Number 4820-00-274-1349, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 25 specifications, cited from the U.S. Government catalog. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 4 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-274-1349 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Nominal Pipe Size Accommodated | 0.250 INCHES FIRST END IN |
| Nominal Pipe Size Accommodated | 0.250 INCHES SECOND END IN |
| Connection Style | PLAIN,OPTIONAL END(PIPE) SECOND END |
| Connection Style | PLAIN (PIPE) FIRST END |
| Connection Type | THREADED INTERNAL PIPE SECOND END |
| Connection Type | THREADED EXTERNAL PIPE FIRST END |
| Style Designator | ANGLE |
| Features Provided | PRESSURE TIGHT OUTLET SIDE |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.250 INCHES FIRST END IN |
| Nominal Thread Size | 0.250 INCHES SECOND END IN |
| Disk Loading Method | SPRING |
| Thread Quantity Per Inch | 18 FIRST END |
| Thread Quantity Per Inch | 18 SECOND END |
| Material | COPPER ALLOY BODY |
| Material | NICKEL ALLOY SEAT |
| Material | COPPER ALLOY STEM |
| Material | COPPER ALLOY AND NICKEL ALLOY FLOW CONTROL DEVICE |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | NPT FIRST END |
| Opening Pressure Setting | 235.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Reference Number Differentiating Characteristics | AS DIFFERENTIATED IN REPLY TO PAC ADSV ACLG AND ACMN |
| 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 |
|---|---|
| 282-4900-801776PCV18 | 5/1 Secondary reference U.S. Government activity |
| 43835PC1T012 | 5/1 Secondary reference U.S. Government activity |
| 4824-934713PC1T012 | 3/1 Design control — primary reference U.S. Government activity |
| 4824-158796PC1-4-210 | 5/1 Secondary reference U.S. Government activity |
| 4824-158796PC1-4-235 | 5/1 Secondary reference U.S. Government activity |
NSN 4820-00-274-1349 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
4 possible matches (shared part number, not a government interchangeability claim): 4820-00-274-1510, 4820-00-287-4637, 4820-00-287-4642. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-274-1349: Flow Control Device: POPPET; Nominal Pipe Size Accommodated: 0.250 INCHES FIRST END IN; Nominal Pipe Size Accommodated: 0.250 INCHES SECOND END IN; Connection Style: PLAIN,OPTIONAL END(PIPE) SECOND END. 25 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.