The Seat,valve, cataloged under National Stock Number 4820-01-142-1636, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 9 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-142-1636 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Thread Length | 0.563 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | PLAIN THREADED |
| Body Inside Diameter | 3.938 INCHES NOMINAL IN |
| Nominal Thread Size | 4.812 INCHES SINGLE THREADED PORTION IN |
| Thread Class | 3A SINGLE THREADED PORTION A |
| Thread Quantity Per Inch | 12 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 |
|---|---|
| 803-2177917 | D/9 Drawing number reference only U.S. Government activity |
| 803-2177917-04-02 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-142-1636 is a Seat,valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-142-1636: Overall Height: 0.688 INCHES NOMINAL IN; Thread Length: 0.563 INCHES NOMINAL SINGLE THREADED PORTION IN; Style Designator: PLAIN THREADED; Body Inside Diameter: 3.938 INCHES NOMINAL IN. 9 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.