The Valve,safety Relief, cataloged under National Stock Number 4820-00-554-9937, 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23 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-554-9937 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | FLARED (TUBE) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL TUBE SECOND END |
| Style Designator | ANGLE |
| Nominal Outside Diameter Tube Accommodated | 0.375 INCHES FIRST END IN |
| Adjustable Pressure Range | +115.0 TO 250.0 POUNDS PER SQUARE INCH LBS |
| Features Provided | VALVE STEM LOCK SHIELD AND PRESSURE TIGHT OUTLET SIDE |
| Bonnet Type | INSIDE SPRING |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.562 INCHES FIRST END IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Bonnet Attachment Method | THREADED |
| Thread Class | 3A FIRST END A |
| Thread Quantity Per Inch | 18 FIRST END |
| Material | STEEL CORROSION RESISTING FLOW CONTROL DEVICE |
| Material | ALUMINUM ALLOY SEAT |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | UNF FIRST END |
| Valve Discharge Flow Rate | 2.0 GALLONS PER MINUTE |
| 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 |
|---|---|
| 624X4-6 | 5/9 Secondary reference U.S. Government activity |
| 10-1156-9 | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-00-554-9937 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-554-9937: Flow Control Device: DISK; Connection Style: FLARED (TUBE) FIRST END; Connection Type: THREADED EXTERNAL TUBE FIRST END; Connection Type: THREADED EXTERNAL TUBE SECOND 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.