The Gear,helical, cataloged under National Stock Number 3020-00-391-4091, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. The manufacturer of record is Hatch & Kirk, Inc.. Government technical data includes 21 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-391-4091 |
| Primary Part Number | 3271930 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Hatch & Kirk, Inc. |
| Status | ACTIVE |
| Bore Nominal Diameter | 1.956 INCHES BOTH ENDS IN |
| Helix Angle | 25.8167 DEGREES |
| Hub Nominal Diameter | 2.997 INCHES FIRST END IN |
| Hub Nominal Diameter | 2.997 INCHES SECOND END IN |
| Teeth Quantity | 58 |
| Body Style | WEBBED, SOLID |
| Tooth Direction | LEFT |
| Bore Style | STRAIGHT SPLINE BOTH ENDS |
| Nominal Distance Between Body Face and Protruding Hub End | 0.813 INCHES BOTH ENDS IN |
| Teeth Type | SINGLE HELIX |
| Hardness Rating | 10.0 ROCKWELL C MINIMUM AND 13.0 ROCKWELL C MAXIMUM OVERALL |
| Style Designator | PROTRUDING HUBS |
| Material Document and Classification | MIL-S-890,CLASS B MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 7.2500 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Hub Style Designator | PLAIN BOTH ENDS |
| Spline Quantity | 6 BOTH ENDS |
| Nominal Outside Diameter | 7.499 INCHES IN |
| Pressure Angle | 14.5000 DEGREES |
| Material | STEEL OVERALL |
| Face Nominal Width | 1.750 INCHES IN |
| 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 |
|---|---|
| 3271930 PRIMARY | Hatch & Kirk, Inc. (USA) |
| Reference | Meaning |
|---|---|
| 3271930 | 5/9 Secondary reference General Motors Corp Electro-Motive Div |
NSN 3020-00-391-4091 is a Gear,helical, manufactured by Hatch & Kirk, Inc., classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-391-4091 has 1 manufacturer part number on file: 3271930 (Hatch & Kirk, Inc.).
Key specifications for 3271930: Bore Nominal Diameter: 1.956 INCHES BOTH ENDS IN; Helix Angle: 25.8167 DEGREES; Hub Nominal Diameter: 2.997 INCHES FIRST END IN; Hub Nominal Diameter: 2.997 INCHES SECOND END IN. 21 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.