The Seat,valve, cataloged under National Stock Number 4820-00-678-4345, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-00-678-4345 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.498 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN |
| Flange Diameter | 2.626 INCHES MINIMUM AND 2.631 INCHES MAXIMUM IN |
| Body Outside Diameter | 2.122 INCHES MINIMUM AND 2.123 INCHES MAXIMUM IN |
| Taper Minor Diameter | 1.125 INCHES MINIMUM AND 1.128 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,CLASS 410 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Taper Major Diameter | 1.448 INCHES MINIMUM AND 1.454 INCHES MAXIMUM IN |
| Body Inside Diameter | 1.448 INCHES MINIMUM AND 1.454 INCHES MAXIMUM IN |
| Seat Radius | 0.337 INCHES NOMINAL IN |
| Under Flange Height | 1.414 INCHES MINIMUM AND 1.924 INCHES MAXIMUM 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 | X |
| Reference | Meaning |
|---|---|
| B3291860REVAPC1 | 5/2 Secondary reference U.S. Government activity |
| 7027E58AXPC31 | 5/9 Secondary reference General Electric Company |
| 101B354BF1 | 3/9 Design control — primary reference General Electric Co Naval and Drive Turbine Systems Dept |
NSN 4820-00-678-4345 is a Seat,valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-678-4345: Flange Seat to Disk End Height: 0.498 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN; Flange Diameter: 2.626 INCHES MINIMUM AND 2.631 INCHES MAXIMUM IN; Body Outside Diameter: 2.122 INCHES MINIMUM AND 2.123 INCHES MAXIMUM IN; Taper Minor Diameter: 1.125 INCHES MINIMUM AND 1.128 INCHES MAXIMUM IN. 14 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.