The Gear,spur, cataloged under National Stock Number 3020-01-139-2435, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. Government technical data includes 22 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 3020-01-139-2435 |
| Item Name | Gear,spur |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Status | ACTIVE |
| Bore Nominal Diameter | 4.000 INCHES BOTH ENDS4.000 INCHES BOTH ENDS IN |
| Hub Nominal Diameter | 4.906 INCHES FIRST END4.906 INCHES FIRST END IN |
| Teeth Quantity | 4242 |
| Body Style | WEBBED, SOLIDWEBBED, SOLID |
| Bore Style | INVOLUTE SPLINE BOTH ENDSINVOLUTE SPLINE BOTH ENDS |
| Mounting Hole Type and Quantity | 6 THREADED AXIALLY THROUGH BODY FIRST END6 THREADED AXIALLY THROUGH BODY FIRST END |
| Nominal Distance Between Body Face and Protruding Hub End | 0.370 INCHES FIRST END0.370 INCHES FIRST END IN |
| Hardness Rating | 42.0 ROCKWELL C MINIMUM AND 42.0 ROCKWELL C MINIMUM AND 28.0 ROCKWELL C MAXIMUM TEETH28.0 ROCKWELL C MAXIMUM TEETH |
| Style Designator | ONE PROTRUDING HUB, ONE FLUSH HUBONE PROTRUDING HUB, ONE FLUSH HUB |
| Pitch Diameter | 8.4894 INCHES NOMINAL8.4894 INCHES NOMINAL IN |
| Tooth Form | STANDARDSTANDARD |
| Hub Style Designator | PLAIN FIRST ENDPLAIN FIRST END |
| Spline Quantity | 64 BOTH ENDS64 BOTH ENDS |
| Mounting Hole Nominal Thread Size | 0.312 INCHES AXIALLY THROUGH BODY FIRST END0.312 INCHES AXIALLY THROUGH BODY FIRST END IN |
| Nominal Outside Diameter | 8.793 INCHES8.793 INCHES IN |
| Pressure Angle | 25.0000 DEGREES25.0000 DEGREES |
| Material | STEEL OVERALL |
| Bolt Hole Circle Nominal Diameter | 4.875 INCHES AXIALLY THROUGH BODY FIRST END4.875 INCHES AXIALLY THROUGH BODY FIRST END IN |
| Mounting Hole Thread Series Designator | UNF AXIALLY THROUGH BODY FIRST ENDUNF AXIALLY THROUGH BODY FIRST END |
| Spline Pitch Diameter | 4.0000 INCHES NOMINAL BOTH ENDS4.0000 INCHES NOMINAL BOTH ENDS IN |
| Attachment Method | MOUNTING HOLEMOUNTING HOLE |
| Face Nominal Width | 1.130 INCHES1.130 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 |
|---|---|
| 2600453 | 3/2 Design control — primary reference U.S. Government activity |
NSN 3020-01-139-2435 is a Gear,spur, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
Key specifications for 3020-01-139-2435: Bore Nominal Diameter: 4.000 INCHES BOTH ENDS4.000 INCHES BOTH ENDS IN; Hub Nominal Diameter: 4.906 INCHES FIRST END4.906 INCHES FIRST END IN; Teeth Quantity: 4242; Body Style: WEBBED, SOLIDWEBBED, SOLID. 22 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.