The Valve,safety Relief, cataloged under National Stock Number 4820-01-261-0163, 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23 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-261-0163 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | GASKET SEAL(BOSS) SECOND END |
| Connection Style | FLARED (TUBE) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED INTERNAL BOSS SECOND END |
| Style Designator | STRAIGHT THRU |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.438 INCHES ALL ENDS IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Media for Which Designed | ALCOHOL, ETHYL SECOND RESPONSE |
| Media for Which Designed | AMMONIA, GASEOUS THIRD RESPONSE |
| Media for Which Designed | REFRIGERANT 12 FIFTH RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Media for Which Designed | AMMONIA, LIQUID FOURTH RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Class | 3B SECOND END |
| Material | ALUMINUM BODY |
| Material | RUBBER SYNTHETIC SEAT |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) FIRST END |
| Thread Series Designator | UNF SECOND END |
| Opening Pressure Setting | 1500.0 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 |
|---|---|
| 332-2246-060 | 7/1 Vendor item drawing reference Rockwell Collins, Inc. Dba Collins Aerospace Government Systems Div Collins Aerospace - Government Systems |
| 332-2246 | D/9 Drawing number reference only Rockwell Collins, Inc. Dba Collins Aerospace Government Systems Div Collins Aerospace - Government Systems |
| 332-2246-060 | 5/2 Secondary reference U.S. Government activity |
| 5177A-4TB-1500 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-261-0163 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-261-0163: Flow Control Device: POPPET; Connection Style: GASKET SEAL(BOSS) SECOND END; Connection Style: FLARED (TUBE) FIRST END; Connection Type: THREADED EXTERNAL TUBE FIRST END. 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.