The Valve,safety Relief, cataloged under National Stock Number 4820-00-083-1256, 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18 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-083-1256 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | GASKET SEAL(BOSS) FIRST END |
| Style Designator | STRAIGHT THRU |
| Bonnet Type | PACKING RETAINING |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 1.062 INCHES FIRST END IN |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE LOCATION NOT OTHERWISE SPECIFIED |
| Thread Class | 3B FIRST END |
| Thread Quantity Per Inch | 12 FIRST END |
| Material | STEEL CORROSION RESISTING FLOW CONTROL DEVICE |
| Material | STEEL CORROSION RESISTING SEAT |
| Material | ALUMINUM ALLOY BODY |
| Material | STEEL CORROSION RESISTING STEM |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) FIRST END |
| Opening Pressure Setting | 3560.00 POUNDS PER SQUARE INCH LBS |
| Valve Discharge Flow Rate | 32.0 GALLONS PER MINUTE |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | N |
| Reference | Meaning |
|---|---|
| 128SCH136-7 | 7/9 Vendor item drawing reference Northrop Grumman Systems Corporation |
| A90122 | 3/2 Design control — primary reference U.S. Government activity |
| 128SCH136-7 | C/1 Advisory reference — outside the item-of-supply concept Northrop Grumman Systems Corporation |
NSN 4820-00-083-1256 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-083-1256: Flow Control Device: POPPET; Connection Style: GASKET SEAL(BOSS) FIRST END; Style Designator: STRAIGHT THRU; Bonnet Type: PACKING RETAINING. 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.
NSN 4820-00-083-1256 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
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.