The Gear,helical, cataloged under National Stock Number 3020-00-138-2019, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. Government technical data includes 18 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-138-2019 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Status | ACTIVE |
| Keyway Nominal Width | 0.250 INCHES BOTH ENDS IN |
| Bore Nominal Diameter | 1.813 INCHES BOTH ENDS IN |
| Helix Angle | 11.7165 DEGREES |
| Teeth Quantity | 76 |
| Body Style | WEBBED, SOLID |
| Tooth Direction | LEFT |
| Bore Style | W/ KEYWAY BOTH ENDS |
| Teeth Type | SINGLE HELIX |
| Hardness Rating | 44.0 ROCKWELL C MINIMUM AND 48.0 ROCKWELL C MAXIMUM OVERALL |
| Style Designator | FLUSH HUB |
| Material Document and Classification | AISI/SAE 4142 H ASSN STD SINGLE MATERIAL RESPONSE AND FED STD 66 FED STD SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 4.8511 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Nominal Outside Diameter | 4.911 INCHES IN |
| Nominal Distance From Bore Center to Keyway Bottom | 1.032 INCHES BOTH ENDS IN |
| Pressure Angle | 20.0000 DEGREES |
| Material | STEEL COMP 4142H 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 |
| Reference | Meaning |
|---|---|
| A116297 | 3/9 Design control — primary reference Emerson Electric Co U S Electrical Motors Div |
NSN 3020-00-138-2019 is a Gear,helical, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
Key specifications for 3020-00-138-2019: Keyway Nominal Width: 0.250 INCHES BOTH ENDS IN; Bore Nominal Diameter: 1.813 INCHES BOTH ENDS IN; Helix Angle: 11.7165 DEGREES; Teeth Quantity: 76. 18 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.