The Valve,safety Relief, cataloged under National Stock Number 4820-01-471-6589, 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12 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-471-6589 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Connection Style | PLAIN (PIPE) ALL ENDS |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Features Provided | BONNET PACKING AND PRESSURE TIGHT OUTLET SIDE |
| Bonnet Type | INSIDE SPRING |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 1.750 INCHES FIRST END IN |
| Nominal Thread Size | 2.313 INCHES SECOND END IN |
| Bonnet Attachment Method | THREADED |
| Material | NICKEL ALLOY BODY |
| Material | NICKEL ALLOY 625 SEAT |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 960.0 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 |
|---|---|
| PLC-12494-960 PSI | 3/2 Design control — primary reference U.S. Government activity |
| PLC-12494 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-471-6589 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-471-6589: Connection Style: PLAIN (PIPE) ALL ENDS; Connection Type: THREADED EXTERNAL TUBE ALL ENDS; Features Provided: BONNET PACKING AND PRESSURE TIGHT OUTLET SIDE; Bonnet Type: INSIDE SPRING. 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.