The Valve,safety Relief, cataloged under National Stock Number 4820-00-001-0037, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 26 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-001-0037 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Nominal Pipe Size Accommodated | 0.375 INCHES FIRST END IN |
| Surface Treatment Document and Classification | MIL-A-8625,TY 1 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED |
| Connection Style | PLAIN (PIPE) FIRST END |
| Style Designator | STRAIGHT THRU W/BAFFLE |
| Material Document and Classification | QQ-A-225/6,ALLOY2024,T4 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-A-225/6,ALLOY2024,T4 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Material Document and Classification | QQ-A-225/6,ALLOY2024,T4 FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Operating Pressure | 200.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Bonnet Type | INSIDE SCREW |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.375 INCHES FIRST END IN |
| Maximum Operating Temp | 280.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Bonnet Attachment Method | THREADED |
| Media for Which Designed | FUEL/OIL, HYDROCARBON THIRD RESPONSE |
| Media for Which Designed | HELIUM SECOND RESPONSE |
| Media for Which Designed | HYDROGEN FOURTH RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Material | ALUMINUM ALLOY 2024 BODY |
| Material | ALUMINUM ALLOY 2024 AND RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR FLOW CONTROL DEVICE |
| Material | ALUMINUM ALLOY 2024 SEAT |
| Thread Series Designator | NPT FIRST END |
| Opening Pressure Setting | 2.0 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 |
|---|---|
| D559A3M2 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-00-001-0037 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-001-0037: Flow Control Device: POPPET; Nominal Pipe Size Accommodated: 0.375 INCHES FIRST END IN; Surface Treatment Document and Classification: MIL-A-8625,TY 1 MIL SPEC SINGLE TREATMENT RESPONSE LOCATION NOT OTHERWISE SPECIFIED; Connection Style: PLAIN (PIPE) FIRST END. 26 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.