The Valve,safety Relief, cataloged under National Stock Number 4820-01-425-6825, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-425-6825 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Connection Style | PLAIN (PIPE) SECOND END |
| Connection Type | THREADED EXTERNAL PIPE SECOND END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Style Designator | ANGLE |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.625 INCHES FIRST END IN |
| Nominal Thread Size | 0.500 INCHES SECOND END IN |
| Thread Class | 3A FIRST END A |
| Material | COPPER ALLOY BODY |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | UNF FIRST END |
| Opening Pressure Setting | 275.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| 9168377-2 | C/1 Advisory reference — outside the item-of-supply concept Drs Environmental Systems Inc |
| 527-275PSI | 3/9 Design control — primary reference Henry Technologies, Inc. |
| 9168377-2 | 5/9 Secondary reference U.S. Government activity |
| 9168377 | 5/9 Secondary reference U.S. Government activity |
NSN 4820-01-425-6825 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-425-6825: Connection Style: PLAIN (PIPE) SECOND END; Connection Type: THREADED EXTERNAL PIPE SECOND END; Connection Type: THREADED EXTERNAL TUBE FIRST END; Style Designator: ANGLE. 14 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.