PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21978Gear,bevel

Todd Combustion Inc · NSN 3020-01-018-1822 · FSC 3020 · No Item Name Available
Verified by PartsTable
NSN 3020-01-018-1822 — this item is cataloged by the U.S. Government under National Stock Number 3020-01-018-1822. Primary manufacturer part number: 21978.
Features
  • Gear,bevel — FSC 3020
  • Mounting Hole Nominal Thread Size: 0.250 INCHES AXIALLY THROUGH BODY FIRST END IN
  • Mounting Hole Type and Quantity: 3 THREADED AXIALLY THROUGH BODY FIRST END
  • Teeth Quantity: 60
  • Pitch Diameter: 6.0000 INCHES NOMINAL IN
  • Nominal Outside Diameter: 6.060 INCHES IN
  • Teeth Type: STRAIGHT
  • Pitch Angle: 15.0000 DEGREES
Applications
  • Power transmission and speed reduction
  • Rotary motion transfer
  • Torque multiplication
  • Applications requiring Steel Overall construction
General Description

The Gear,bevel, cataloged under National Stock Number 3020-01-018-1822, is classified within Federal Supply Class 3020 (No Item Name Available) of the Mechanical Power Transmission Equipment group. The primary manufacturer of record is Todd Combustion Inc. Government technical data includes 21 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 9 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 8 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.

Technical Specifications
ParameterValue
NSN3020-01-018-1822
Primary Part Number21978
Item NameGear,bevel
FSC / FSG3020 / 30 — No Item Name Available
ManufacturerTodd Combustion Inc
StatusCANCELLED
Mounting Hole Nominal Thread Size0.250 INCHES AXIALLY THROUGH BODY FIRST END IN
Mounting Hole Type and Quantity3 THREADED AXIALLY THROUGH BODY FIRST END
Teeth Quantity60
Pitch Diameter6.0000 INCHES NOMINAL IN
Nominal Outside Diameter6.060 INCHES IN
Teeth TypeSTRAIGHT
Pitch Angle15.0000 DEGREES
Mounting Hole Thread Series DesignatorUNIFIED NATIONAL COARSE (UNC) AXIALLY THROUGH BODY FIRST END
MaterialSTEEL OVERALL
Hub Style DesignatorPLAIN SECOND END
Style DesignatorPERIPHERAL FACE, BACK HUB PROTRUDING
Bore Nominal Diameter4.015 INCHES BOTH ENDS IN
Bore StylePLAIN BOTH ENDS
Bolt Hole Circle Nominal Diameter5.158 INCHES AXIALLY THROUGH BODY FIRST END IN
Hub Nominal Diameter4.473 INCHES SECOND END IN
Nominal Distance Between Body Face and Protruding Hub End0.250 INCHES SECOND END IN
Face Nominal Width0.517 INCHES IN
Nominal Overall Length2.000 INCHES IN
Pressure Angle20.0000 DEGREES
Attachment MethodMOUNTING HOLE
Body StylePLAIN, WITH LIGHTENING HOLES
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 8
1650-00-123-027211-661-7-1 INTERCHANGEABLE
Boot,deicer
Goodrich Corporation
4820-00-139-5425 INTERCHANGEABLE
Valve Assembly
5330-00-154-090311800 INTERCHANGEABLE
Seal,plain Encased
Skf Usa Inc. Dba Skf Aerospace Sealing Solutions
5110-00-348-4778GH343 INTERCHANGEABLE
Reamer,hand
Sioux Tools Inc
2805-00-360-792100119136 INTERCHANGEABLE
Guide,valve Stem
Am General Llc
5831-00-565-8621G343 INTERCHANGEABLE
Panelaudio Selector
Gables Engineering, Inc. Dba Gables Engineering Inc Div Coral Gables
3610-00-773-5663 INTERCHANGEABLE
Box,roller,left
4530-01-018-241110576 INTERCHANGEABLE
Quadrant,operating Spur Gear
Todd Combustion Inc
Cross-Reference Index
Part NumberManufacturer
N49704PC18 Todd Combustion Inc (USA)
21978 PRIMARY Todd Combustion Inc (USA)
DD936-S5501-1499308 Naval Ship Systems Command (USA)
N46640PC18 Todd Combustion Inc (USA)
N49677PC18 Todd Combustion Inc (USA)
DD936-S5501-1499308PC18 Naval Ship Systems Command (USA)
ND40069PC18 Todd Combustion Inc (USA)
G3-4-3 PRIMARY Todd Combustion Inc (USA)
DD936-S5501-149 Naval Ship Systems Command (USA)
Related Parts
1650-00-123-0272INTERCHANGEABLE
BOOT,DEICER
11-661-7-1
4820-00-139-5425INTERCHANGEABLE
VALVE ASSEMBLY
5330-00-154-0903INTERCHANGEABLE
SEAL,PLAIN ENCASED
11800
5110-00-348-4778INTERCHANGEABLE
REAMER,HAND
GH343
2805-00-360-7921INTERCHANGEABLE
GUIDE,VALVE STEM
00119136
5831-00-565-8621INTERCHANGEABLE
PANELAUDIO SELECTOR
G343
3610-00-773-5663INTERCHANGEABLE
BOX,ROLLER,LEFT
4530-01-018-2411INTERCHANGEABLE
QUADRANT,OPERATING SPUR GEAR
10576

Frequently Asked Questions

What is NSN 3020-01-018-1822?

NSN 3020-01-018-1822 is a Gear,bevel, manufactured by Todd Combustion Inc, classified under FSC 3020 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 3020-01-018-1822?

NSN 3020-01-018-1822 has 9 cross-referenced part numbers: N49704PC18 (Todd Combustion Inc), 21978 (Todd Combustion Inc), DD936-S5501-1499308 (Naval Ship Systems Command), N46640PC18 (Todd Combustion Inc), N49677PC18 (Todd Combustion Inc) and 4 more.

What NSN replaces 3020-01-018-1822?

There are 8 known substitutes for 3020-01-018-1822: 1650-00-123-0272, 4820-00-139-5425, 5330-00-154-0903 and 5 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 21978?

Key specifications for 21978: Mounting Hole Nominal Thread Size: 0.250 INCHES AXIALLY THROUGH BODY FIRST END IN; Mounting Hole Type and Quantity: 3 THREADED AXIALLY THROUGH BODY FIRST END; Teeth Quantity: 60; Pitch Diameter: 6.0000 INCHES NOMINAL IN. 21 total characteristics are documented in the Federal Logistics Information System.

Is NSN 3020-01-018-1822 still in active supply?

NSN 3020-01-018-1822 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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