The Seat,valve, cataloged under National Stock Number 4820-01-220-2050, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Siemens Energy, Inc.. Government technical data includes 3 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-220-2050 |
| Primary Part Number | 51693-7 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Siemens Energy, Inc. |
| Status | ACTIVE |
| Body Outside Diameter | 3.250 INCHES NOMINAL IN |
| Material Document and Classification | MIL-B-16541 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Material | COPPER ALLOY 922 OVERALL |
| 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 |
|---|---|
| 51693-7 PRIMARY | Siemens Energy, Inc. (USA) |
| Reference | Meaning |
|---|---|
| F-3,105,162 PIECE 7 | 5/2 Secondary reference U.S. Government activity |
| F-3,105,162 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-220-2050 is a Seat,valve, manufactured by Siemens Energy, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-220-2050 has 1 manufacturer part number on file: 51693-7 (Siemens Energy, Inc.).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-220-2172, 4820-01-220-2301. Verify interchangeability with system specifications before substitution.
Key specifications for 51693-7: Overall Height: 0.565 INCHES NOMINAL IN; Body Outside Diameter: 3.250 INCHES NOMINAL IN; Material Document and Classification: MIL-B-16541 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL; Material: COPPER ALLOY 922 OVERALL. 3 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.