The Gear,helical, cataloged under National Stock Number 3020-00-239-5532, 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 Siemens Energy, Inc.. Government technical data includes 22 specifications, cited from the U.S. Government catalog. The record lists 5 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 11 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-239-5532 |
| Primary Part Number | G-9818 PIECE 121 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Siemens Energy, Inc. |
| Status | ACTIVE |
| Keyway Nominal Width | 0.1865 INCHES BOTH ENDS IN |
| Bore Nominal Diameter | 1.005 INCHES BOTH ENDS IN |
| Helix Angle | 44.6967 DEGREES |
| Hub Nominal Diameter | 1.750 INCHES SECOND END IN |
| Hub Nominal Diameter | 1.750 INCHES FIRST END IN |
| Teeth Quantity | 31 |
| Body Style | PLAIN, SOLID |
| Tooth Direction | RIGHT |
| Bore Style | W/ KEYWAY BOTH ENDS |
| Nominal Distance Between Body Face and Protruding Hub End | 0.375 INCHES FIRST END IN |
| Nominal Distance Between Body Face and Protruding Hub End | 0.094 INCHES SECOND END IN |
| Teeth Type | SINGLE HELIX |
| Style Designator | PROTRUDING HUBS |
| Material Document and Classification | MIL-S-890,CLASS AN MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 2.3189 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Hub Style Designator | PLAIN BOTH ENDS |
| Nominal Outside Diameter | 2.4189 INCHES IN |
| Nominal Distance From Bore Center to Keyway Bottom | 0.593 INCHES BOTH ENDS IN |
| Pressure Angle | 15.0000 DEGREES |
| Material | STEEL OVERALL |
| Face Nominal Width | 0.500 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 |
|---|---|
| G7908PC132 | Siemens Energy, Inc. (USA) |
| G7804PC132 | Siemens Energy, Inc. (USA) |
| G7902PC132 | Siemens Energy, Inc. (USA) |
| G7798PC132 | Siemens Energy, Inc. (USA) |
| G-9818 PIECE 121 PRIMARY | Siemens Energy, Inc. (USA) |
| Reference | Meaning |
|---|---|
| W416CSX4 | 5/9 Secondary reference Imo Industries Inc Delroyd Worm Gear Div |
| W416CSX4 | 5/9 Secondary reference Siemens Energy, Inc. |
| G9987PC132 | 5/9 Secondary reference Siemens Energy, Inc. |
| G9760PC132 | 5/9 Secondary reference Imo Industries Inc Delroyd Worm Gear Div |
| W416CS4 | C/1 Advisory reference — outside the item-of-supply concept Siemens Energy, Inc. |
| G9981PC132 | 5/9 Secondary reference Imo Industries Inc Delroyd Worm Gear Div |
| G9987PC132 | 5/9 Secondary reference Imo Industries Inc Delroyd Worm Gear Div |
| G9981PC132 | 5/9 Secondary reference Siemens Energy, Inc. |
| G9754PC132 | 5/9 Secondary reference Imo Industries Inc Delroyd Worm Gear Div |
| G9760PC132 | 5/9 Secondary reference Siemens Energy, Inc. |
| G9754PC132 | 5/9 Secondary reference Siemens Energy, Inc. |
NSN 3020-00-239-5532 is a Gear,helical, manufactured by Siemens Energy, Inc., classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-239-5532 has 5 manufacturer part numbers on file: G7908PC132 (Siemens Energy, Inc.), G7804PC132 (Siemens Energy, Inc.), G7902PC132 (Siemens Energy, Inc.), G7798PC132 (Siemens Energy, Inc.), G-9818 PIECE 121 (Siemens Energy, Inc.).
Key specifications for G-9818 PIECE 121: Keyway Nominal Width: 0.1865 INCHES BOTH ENDS IN; Bore Nominal Diameter: 1.005 INCHES BOTH ENDS IN; Helix Angle: 44.6967 DEGREES; Hub Nominal Diameter: 1.750 INCHES SECOND END IN. 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.