The Valve,safety Relief, cataloged under National Stock Number 4820-01-550-7997, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 8 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-550-7997 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Material Document and Classification | MIL-B-24480 MIL SPEC SINGLE MATERIAL RESPONSE BODY |
| Operating Pressure | 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Maximum Operating Temp | 225.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Material | COPPER ALLOY BODY |
| 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 |
|---|---|
| 158 PL-5052/.156 5500PSI SET | 3/2 Design control — primary reference U.S. Government activity |
| PL-5052 | D/9 Drawing number reference only U.S. Government activity |
| A-10851 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-550-7997 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 4820-01-564-7796. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-550-7997: Connection Type: THREADED EXTERNAL PIPE ALL ENDS; Style Designator: ANGLE; Material Document and Classification: MIL-B-24480 MIL SPEC SINGLE MATERIAL RESPONSE BODY; Operating Pressure: 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS. 8 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.