The Valve,safety Relief, cataloged under National Stock Number 4820-01-559-5509, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Navy, United States Department of the Dba Naval Surface Warfare Center Div Naval Surface Warfare Center Crane Division. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-559-5509 |
| Primary Part Number | 802027213967-1 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Navy, United States Department of the Dba Naval Surface Warfare Center Div Naval Surface Warfare Center Crane Division |
| Status | ACTIVE |
| Connection Type | THREADED INTERNAL PIPE SECOND END |
| Connection Type | THREADED EXTERNAL PIPE FIRST END |
| Style Designator | STRAIGHT THRU |
| Valve Size | 0.250 INCHES IN |
| Material | STEEL COMP 316 BODY |
| Opening Pressure Setting | 50.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL B — Remove Demilitarization Key Points |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 802027213967-1 | Navy, United States Department of the Dba Naval Surface Warfare Center Div Naval Surface Warfare Center Crane Division (USA) |
| Reference | Meaning |
|---|---|
| 520T1-2MP-50 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-559-5509 is a Valve,safety Relief, manufactured by Navy, United States Department of the Dba Naval Surface Warfare Center Div Naval Surface Warfare Center Crane Division, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-559-5509 has 1 manufacturer part number on file: 802027213967-1 (Navy, United States Department of the Dba Naval Surface Warfare Center Div Naval Surface Warfare Center Crane Division).
Key specifications for 802027213967-1: Connection Type: THREADED INTERNAL PIPE SECOND END; Connection Type: THREADED EXTERNAL PIPE FIRST END; Style Designator: STRAIGHT THRU; Valve Size: 0.250 INCHES IN. 7 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 4820-01-559-5509 has DEMIL Code B. 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.