The Valve,safety Relief, cataloged under National Stock Number 4820-01-159-5881, 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18 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-159-5881 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | OVAL WITH HOLES FIRST END |
| Flange Face Design | RAISED STRAIGHT FIRST END |
| Nominal Length | 3.750 INCHES FIRST END IN |
| Bolt Circle Nominal Diameter | 2.750 INCHES FIRST END IN |
| Connection Type | UNTHREADED INTERNAL TUBE SECOND END |
| Connection Type | FLANGE FIRST END |
| Style Designator | ANGLE |
| Bolt Hole Nominal Diameter | 0.525 INCHES FIRST END IN |
| Nominal Outside Diameter Tube Accommodated | 1.125 INCHES SECOND END IN |
| Bolt Hole Quantity | 2 FIRST END |
| Nominal Width | 2.298 INCHES FIRST END IN |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| Material | IRON BODY |
| Raised Face Nominal Diameter | 2.000 INCHES FIRST END IN |
| Valve Operation Method | AUTOMATIC |
| Raised Face Nominal Height | 0.125 INCHES FIRST END IN |
| Nominal Thickness | 1.188 INCHES FIRST END IN |
| 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 |
|---|---|
| 4931050063 | 3/9 Design control — primary reference Air Products & Chemicals, Inc |
NSN 4820-01-159-5881 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-159-5881: Flow Control Device: DISK; Flange Shape: OVAL WITH HOLES FIRST END; Flange Face Design: RAISED STRAIGHT FIRST END; Nominal Length: 3.750 INCHES FIRST END IN. 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.