The Valve,safety Relief, cataloged under National Stock Number 4820-00-535-1623, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 18 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-00-535-1623 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | PISTON |
| Renewable Seat Ring Type | PRESSED-IN |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Adjustable Pressure Range | +2500.0 TO 5000.0 POUNDS PER SQUARE INCH LBS |
| Features Provided | PRESSURE TIGHT OUTLET SIDE |
| Bonnet Type | INSIDE SPRING |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES SECOND END IN |
| Nominal Thread Size | 0.500 INCHES FIRST END IN |
| Disk Loading Method | SPRING |
| Bonnet Attachment Method | INTEGRAL |
| Material | STEEL STEM |
| Material | ALUMINUM ALLOY BODY |
| Material | ALUMINUM ALLOY AND STEEL SEAT |
| Thread Series Designator | NPT ALL ENDS |
| Valve Operation Method | MANUAL |
| 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 |
|---|---|
| S214A2500 | 5/9 Secondary reference U.S. Government activity |
| 75323-2 | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-00-535-1623 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-535-1623: Flow Control Device: PISTON; Renewable Seat Ring Type: PRESSED-IN; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Connection Type: THREADED INTERNAL PIPE ALL ENDS. 18 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.