The Valve,safety Relief, cataloged under National Stock Number 4820-00-786-2339, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Triumph Thermal Systems, Llc. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-786-2339 |
| Primary Part Number | U528289 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Triumph Thermal Systems, Llc |
| Status | ACTIVE |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 1.250 INCHES FIRST END IN |
| Features Provided | VALVE STEM LOCK SHIELD AND PRESSURE TIGHT OUTLET SIDE |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 1.500 INCHES FIRST END IN |
| Disk Loading Method | SPRING |
| Surface Treatment | NICKEL LOCATION NOT OTHERWISE SPECIFIED |
| Thread Class | 3A FIRST END A |
| Test Data Document | 78943-U528289 DRAWING (THIS IS THE BASIC GOVERNING DRAWING, SUCH AS A CONTRACTOR DRAWING, ORIGINAL EQUIPMENT MANUFACTURER DRAWING, ETC.; EXCLUDES ANY SPECIFICATION, STANDARD OR OTHER DOCUMENT THAT MAY BE REFERENCED IN A BASIC GOVERNING DRAWING) |
| Thread Quantity Per Inch | 18 FIRST END |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY SEAT |
| Thread Series Designator | UNEF FIRST END |
| Opening Pressure Setting | 5.0 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 |
| Part Number | Manufacturer |
|---|---|
| U528289 PRIMARY | Triumph Thermal Systems, Llc (USA) |
| Reference | Meaning |
|---|---|
| VD10972N | 5/9 Secondary reference U.S. Government activity |
NSN 4820-00-786-2339 is a Valve,safety Relief, manufactured by Triumph Thermal Systems, Llc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-786-2339 has 1 manufacturer part number on file: U528289 (Triumph Thermal Systems, Llc).
Key specifications for U528289: Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) FIRST END; Connection Type: THREADED EXTERNAL TUBE FIRST END; Style Designator: STRAIGHT THRU; Nominal Outside Diameter Tube Accommodated: 1.250 INCHES FIRST END IN. 17 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.