The Valve,safety Relief, cataloged under National Stock Number 4820-01-222-7812, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 24 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-222-7812 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Connection Style | PLAIN (TUBE) FIRST END |
| Connection Style | FLARE(TUBE) SECOND END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED INTERNAL TUBE SECOND END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Material Document and Classification | QQ-A-25/6 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES SECOND END IN |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.438 INCHES ALL ENDS IN |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Media for Which Designed | ACETYLENE SECOND RESPONSE |
| Media for Which Designed | HYDROGEN FOURTH RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Media for Which Designed | REFRIGERANT 12 THIRD RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Class | 3B SECOND END |
| Thread Quantity Per Inch | 18 ALL ENDS |
| Material | ALUMINUM ALLOY 2024 BODY |
| Thread Series Designator | UNS ALL ENDS |
| Opening Pressure Setting | 14.0 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 |
|---|---|
| 807622-1 | 5/2 Secondary reference U.S. Government activity |
| 559A-4DB-14 | 3/2 Design control — primary reference U.S. Government activity |
| 807622 | 7/1 Vendor item drawing reference U.S. Government activity |
NSN 4820-01-222-7812 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-222-7812: Flow Control Device: DISK; Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED; Connection Style: PLAIN (TUBE) FIRST END; Connection Style: FLARE(TUBE) SECOND END. 24 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.