The Valve,safety Relief, cataloged under National Stock Number 4820-00-855-3437, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 12 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-00-855-3437 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Connection Type | THREADED EXTERNAL BOSS FIRST END |
| Style Designator | ANGLE |
| Features Provided | PRESSURE TIGHT OUTLET SIDE |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.625 INCHES FIRST END IN |
| Disk Loading Method | SPRING |
| Thread Quantity Per Inch | 18 FIRST END |
| Material | STEEL CORROSION RESISTING SEAT |
| Material | STEEL CORROSION RESISTING BODY |
| Material | STEEL CORROSION RESISTING STEM |
| Thread Series Designator | UNF FIRST END |
| Opening Pressure Setting | 3000.0 POUNDS PER SQUARE INCH LBS |
| 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 |
|---|---|
| 3053973-4 | 3/9 Design control — primary reference Allied-Signal Inc Dba Allied-Signal Aerospace Co Electrodynamics Div |
NSN 4820-00-855-3437 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-855-3437: Connection Type: THREADED EXTERNAL BOSS FIRST END; Style Designator: ANGLE; Features Provided: PRESSURE TIGHT OUTLET SIDE; Thread Direction: RIGHT-HAND FIRST END. 12 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.