The Valve,safety Relief, cataloged under National Stock Number 4820-01-299-8440, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Swagelok Co. Government technical data includes 8 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-299-8440 |
| Primary Part Number | SS-4R3A |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Swagelok Co |
| Status | ACTIVE |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | ANGLE |
| Operating Pressure | 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +3000.0 TO 4000.0 POUNDS PER SQUARE INCH LBS |
| Disk Loading Method | SPRING |
| Material | STEEL COMP 316 BODY |
| Opening Pressure Setting | 3300.0 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 |
|---|---|
| SS-4R3A PRIMARY | Swagelok Co (USA) |
| 2999C03H04 | Teco-Westinghouse Motor Company (USA) |
| Reference | Meaning |
|---|---|
| 1551AS830-1 | 5/1 Secondary reference Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| SS-4R3A | 5/9 Secondary reference Nupro Co |
| 1370J32 | D/9 Drawing number reference only Teco-Westinghouse Motor Company |
| 1551AS830 | D/9 Drawing number reference only Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
NSN 4820-01-299-8440 is a Valve,safety Relief, manufactured by Swagelok Co, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-299-8440 has 2 manufacturer part numbers on file: SS-4R3A (Swagelok Co), 2999C03H04 (Teco-Westinghouse Motor Company).
Key specifications for SS-4R3A: Connection Type: THREADED EXTERNAL TUBE ALL ENDS; Style Designator: ANGLE; Operating Pressure: 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS; Adjustable Pressure Range: +3000.0 TO 4000.0 POUNDS PER SQUARE INCH LBS. 8 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.