The Valve,safety Relief, cataloged under National Stock Number 4820-00-852-5142, 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23 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-852-5142 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Nominal Pipe Size Accommodated | 0.250 INCHES ALL ENDS IN |
| Surface Treatment Document and Classification | MIL-A-8625,TY 2 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Operating Pressure | 50.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +10.0 TO 50.0 POUNDS PER SQUARE INCH LBS |
| Features Provided | VALVE STEM LOCK SHIELD AND BONNET PACKING |
| Bonnet Type | INSIDE SPRING |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Maximum Operating Temp | 225.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Bonnet Attachment Method | THREADED |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| Thread Quantity Per Inch | 18 ALL ENDS |
| Material | STEEL CORROSION RESISTING AND RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR FLOW CONTROL DEVICE |
| Material | ALUMINUM ALLOY SEAT |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | NPT 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 |
|---|---|
| 627B2 1-4 2 | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-00-852-5142 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 4820-01-195-8456. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-852-5142: Flow Control Device: POPPET; Nominal Pipe Size Accommodated: 0.250 INCHES ALL ENDS IN; Surface Treatment Document and Classification: MIL-A-8625,TY 2 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS. 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.