The Valve,butterfly, cataloged under National Stock Number 4820-01-271-7890, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Dover Resources, Inc. Div Norriseal. Government technical data includes 13 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-271-7890 |
| Primary Part Number | 911-558 |
| Item Name | Valve,butterfly |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Dover Resources, Inc. Div Norriseal |
| Status | ACTIVE |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | ASTM B61 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | ASTM B164 CLASS A ASSN STD SINGLE MATERIAL RESPONSE STEM |
| Material Document and Classification | QQ-N-288 COMP A OR E FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-N-288 COMP A OR E FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Operating Pressure | 200.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Maximum Operating Temp | 400.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Mounting Facility | WAFER |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Material | COPPER ALLOY 922 BODY |
| Material | NICKEL ALLOY 400 STEM |
| Valve Operation Method | MANUAL |
| 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 |
|---|---|
| 911-558 | Dover Resources, Inc. Div Norriseal (USA) |
| 911D558 MDL 2.5D2030-645A-1FM | Dover Resources, Inc. Div Norriseal (USA) |
| Reference | Meaning |
|---|---|
| 911-558 | 5/9 Secondary reference U.S. Government activity |
| 2.5 D2030-645A-1FM | 5/2 Secondary reference U.S. Government activity |
| 911D558 MDL 2.5D2030-645A-1FM | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-01-271-7890 is a Valve,butterfly, manufactured by Dover Resources, Inc. Div Norriseal, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-271-7890 has 2 manufacturer part numbers on file: 911-558 (Dover Resources, Inc. Div Norriseal), 911D558 MDL 2.5D2030-645A-1FM (Dover Resources, Inc. Div Norriseal).
Key specifications for 911-558: Style Designator: STRAIGHT THRU; Material Document and Classification: ASTM B61 ASSN STD SINGLE MATERIAL RESPONSE BODY; Material Document and Classification: ASTM B164 CLASS A ASSN STD SINGLE MATERIAL RESPONSE STEM; Material Document and Classification: QQ-N-288 COMP A OR E FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE. 13 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.