The Gear,helical, cataloged under National Stock Number 3020-00-251-0872, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. Government technical data includes 21 specifications, cited from the U.S. Government catalog. 14 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-251-0872 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Status | ACTIVE |
| Keyway Nominal Width | 0.875 INCHES FIRST END IN |
| Bore Nominal Diameter | 3.4975 INCHES FIRST END IN |
| Helix Angle | 23.0000 DEGREES |
| Hub Nominal Diameter | 5.000 INCHES FIRST END IN |
| Hub Nominal Diameter | 5.000 INCHES SECOND END IN |
| Teeth Quantity | 73 |
| Body Style | SPOKED |
| Tooth Direction | LEFT |
| Bore Style | W/ KEYWAY BOTH ENDS |
| Nominal Distance Between Body Face and Protruding Hub End | 0.125 INCHES FIRST END IN |
| Teeth Type | SINGLE HELIX |
| Style Designator | ONE PROTRUDING HUB, ONE FLUSH HUB |
| Material Document and Classification | MIL-S-15083,GRADE B MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 12.1670 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Hub Style Designator | PLAIN BOTH ENDS |
| Nominal Outside Diameter | 12.4320 INCHES IN |
| Nominal Distance From Bore Center to Keyway Bottom | 0.518 INCHES FIRST END IN |
| Pressure Angle | 20.0000 DEGREES |
| Material | STEEL OVERALL |
| Face Nominal Width | 1.250 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 |
| Reference | Meaning |
|---|---|
| N1262APC6 | 5/9 Secondary reference U.S. Government activity |
| N8350PC6 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| N8352ALTAPC6 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| C2531 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
| N12925ALTAPC6 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| N12262APC6 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| C2531-1 | 5/9 Secondary reference U.S. Government activity |
| C2531-1 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| N8350PC6 | 5/9 Secondary reference U.S. Government activity |
| C2531-2 | 5/9 Secondary reference U.S. Government activity |
| N16268ALTCPC6 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| 2531 | 5/9 Secondary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
| N16268ALTCPC6 | 5/9 Secondary reference U.S. Government activity |
| C2531 | 3/9 Design control — primary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
NSN 3020-00-251-0872 is a Gear,helical, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 1610-01-551-1919. Verify interchangeability with system specifications before substitution.
Key specifications for 3020-00-251-0872: Keyway Nominal Width: 0.875 INCHES FIRST END IN; Bore Nominal Diameter: 3.4975 INCHES FIRST END IN; Helix Angle: 23.0000 DEGREES; Hub Nominal Diameter: 5.000 INCHES FIRST 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.