The Seat,valve, cataloged under National Stock Number 4820-00-594-1998, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Westinghouse Electric Corp. Government technical data includes 15 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-594-1998 |
| Primary Part Number | 1JC8956-6 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Westinghouse Electric Corp |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 1.245 INCHES MINIMUM AND 1.255 INCHES MAXIMUM IN |
| Flange Diameter | 3.042 INCHES MINIMUM AND 3.052 INCHES MAXIMUM IN |
| Body Outside Diameter | 2.562 INCHES MINIMUM AND 2.563 INCHES MAXIMUM IN |
| Seal Accommodation Type | GROOVED |
| Taper Minor Diameter | 0.995 INCHES MINIMUM AND 1.005 INCHES MAXIMUM IN |
| Style Designator | PLAIN FLANGED |
| Material Document and Classification | MIL-R-17131,TYPE MIL-RCOCR-A MIL SPEC SINGLE MATERIAL RESPONSE FACE |
| Material Document and Classification | QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Taper Major Diameter | 1.344 INCHES NOMINAL IN |
| Body Inside Diameter | 1.344 INCHES NOMINAL IN |
| Seat Radius | 0.308 INCHES MINIMUM AND 0.318 INCHES MAXIMUM IN |
| Under Flange Height | 0.938 INCHES NOMINAL IN |
| Material | STEEL BODY |
| Material | COBALT ALLOY FACE |
| Seating Surface Shape | RADIAL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | N |
| Part Number | Manufacturer |
|---|---|
| 1JC8956-6 | Westinghouse Electric Corp (USA) |
| 1JH4864PC43 | Westinghouse Electric Corp (USA) |
| Reference | Meaning |
|---|---|
| 1JC8956-6 | 3/2 Design control — primary reference U.S. Government activity |
| 1JC8956-6 | 5/9 Secondary reference U.S. Government activity |
NSN 4820-00-594-1998 is a Seat,valve, manufactured by Westinghouse Electric Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-594-1998 has 2 manufacturer part numbers on file: 1JC8956-6 (Westinghouse Electric Corp), 1JH4864PC43 (Westinghouse Electric Corp).
Key specifications for 1JC8956-6: Flange Seat to Disk End Height: 1.245 INCHES MINIMUM AND 1.255 INCHES MAXIMUM IN; Flange Diameter: 3.042 INCHES MINIMUM AND 3.052 INCHES MAXIMUM IN; Body Outside Diameter: 2.562 INCHES MINIMUM AND 2.563 INCHES MAXIMUM IN; Seal Accommodation Type: GROOVED. 15 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.