The Valve,safety Relief, cataloged under National Stock Number 4820-01-421-0122, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 23 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-01-421-0122 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Connection Style | GASKET SEAL(BOSS) SECOND END |
| Connection Style | FLARED (TUBE) FIRST END |
| Minimum Operating Temp | -65.0 FAHRENHEIT DEGF |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED INTERNAL BOSS SECOND END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Material Document and Classification | QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OR ASTM A479 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OR ASTM A479 ASSN STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.563 INCHES ALL ENDS IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Maximum Operating Temp | 160.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | PASSIVATE LOCATION NOT OTHERWISE SPECIFIED |
| Media for Which Designed | WATER, FRESH SINGLE RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Class | 3B SECOND END |
| Material | STEEL COMP 316 BODY |
| Material | STEEL COMP 316 FLOW CONTROL DEVICE |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) ALL ENDS |
| 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 |
|---|---|
| RV05-203-06 | 3/2 Design control — primary reference U.S. Government activity |
| 7D0150 | D/9 Drawing number reference only U.S. Government activity |
| 7D0150-06 | 5/2 Secondary reference U.S. Government activity |
NSN 4820-01-421-0122 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-421-0122: Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED; Connection Style: GASKET SEAL(BOSS) SECOND END; Connection Style: FLARED (TUBE) FIRST END; Minimum Operating Temp: -65.0 FAHRENHEIT DEGF. 23 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.