The Seat,valve, cataloged under National Stock Number 4820-00-394-7429, 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14 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-394-7429 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.250 INCHES NOMINAL IN |
| Flange Diameter | 4.500 INCHES NOMINAL IN |
| Thread Length | 0.562 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Body Stepped Inside Diameter | 3.500 INCHES NOMINAL FIRST STEP IN |
| Body Stepped Inside Diameter | 3.625 INCHES NOMINAL SECOND STEP IN |
| Style Designator | THREADED FLANGED |
| Body Inside Diameter | 3.625 INCHES NOMINAL IN |
| Nominal Thread Size | 4.125 INCHES SINGLE THREADED PORTION IN |
| Under Flange Height | 0.562 INCHES NOMINAL IN |
| Thread Class | 2A SINGLE THREADED PORTION A |
| Thread Quantity Per Inch | 14 SINGLE THREADED PORTION |
| Material | NICKEL ALLOY OVERALL |
| Thread Series Designator | UNS SINGLE THREADED PORTION |
| Seating Surface Shape | FLAT |
| 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 |
|---|---|
| P943A | 3/9 Design control — primary reference Atlas Valve Co |
NSN 4820-00-394-7429 is a Seat,valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-394-7429: Flange Seat to Disk End Height: 0.250 INCHES NOMINAL IN; Flange Diameter: 4.500 INCHES NOMINAL IN; Thread Length: 0.562 INCHES NOMINAL SINGLE THREADED PORTION IN; Body Stepped Inside Diameter: 3.500 INCHES NOMINAL FIRST STEP 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.