Top Drive Gearbox Module
The gearbox module within an offshore top drive system transmits power to rotate the drill string on oil/gas platforms (HTS 8431.43.40.00). Designed for harsh marine environments and high-torque requirements of 8430.41/8430.49 boring rigs. A key power transmission part solely for offshore drilling.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If classified as general reduction gearboxes
Plain gearboxes/gearmotors are in 8483; those principally configured for offshore top drives stay in 8431.43.40.
If when part of complete top drive drilling machine
Complete top drive units classify as finished boring machinery in 8430.41, not replacement part gearboxes.
Not sure which classification is right?
Our AI classifier can analyze your specific product and recommend the correct HTS code with confidence.
Import Tips & Compliance
• Specify torque rating (e.g
• 60,000 ft-lbs) and API 7G certification; provide gear ratio/mounting flange drawings matching platform top drives; exclude general gearboxes under 8483
Related Products under HTS 8431.43.40.00
BOP Stack Assembly for Offshore Platforms
A blowout preventer (BOP) stack assembly is a critical safety component designed specifically for offshore oil and natural gas drilling platforms under HTS 8431.43.40.00. It consists of multiple ram and annular preventers mounted on a manifold to seal the wellbore during drilling operations on floating or fixed platforms. Classified here as a part solely for boring machinery of subheading 8430.41 or 8430.49 used offshore.
Offshore Drilling Riser Joint
A marine riser joint connects sections of the riser string used in offshore drilling platforms to convey drilling fluid and guide tools between the rig and subsea wellhead (HTS 8431.43.40.00). These high-pressure, corrosion-resistant pipes are engineered for deepwater environments on platforms using 8430.41/8430.49 boring machinery. Essential for maintaining well control during offshore operations.
Subsea Wellhead Connector
A high-pressure subsea wellhead connector mates the offshore platform's blowout preventer stack to the subsea wellhead in oil and gas drilling operations (HTS 8431.43.40.00). Designed for extreme deepwater pressures and remote operation via ROVs on 8430.41/8430.49 platforms. Classified as a principal part for offshore boring machinery.
Offshore Derrick Crown Block
The crown block is the fixed sheave assembly at the top of an offshore drilling derrick/platform, guiding the drilling line for hoisting operations (HTS 8431.43.40.00). Built to withstand extreme loads on floating production platforms using 8430.41/8430.49 boring equipment. A principal mechanical part for offshore oil/gas drilling rigs.
Platform Tensioner Cylinder Assembly
Hydraulic tensioner cylinders maintain constant tension on offshore drilling risers to compensate for vessel heave motion on floating platforms (HTS 8431.43.40.00). Integral to 8430.41/8430.49 boring machinery for deepwater operations. Classified as parts solely for offshore oil and gas production platforms.
Mud Pump Fluid End Section
The fluid end section of high-pressure mud pumps circulates drilling fluid through offshore platform systems for 8430.41/8430.49 boring machinery (HTS 8431.43.40.00). Contains pistons, valves, and liners exposed to abrasive drilling mud at 5,000+ psi. Exclusive to offshore oil/gas drilling platforms.