Parts
Steam or other vapor generating boilers (other than central heating hot water boilers capable also of producing low pressure steam); super-heated water boilers; parts thereof: > Parts
Duty Rate (from China)
Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
Except as provided in headings 9903.88.05, 9903.88.06, 9903.88.07, 9903.88.08, 9903.88.10, 9903.88.11, 9903.88.14, 9903.88.19, 9903.88.50, 9903.88.52, 9903.88.58, 9903.88.60, 9903.88.62, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(a) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(b) [to this subchapter]
Products classified under HTS 8402.90.00
Tube Sheet for Boiler Headers
Forged tube sheets with drilled holes secure boiler tubes in headers for steam/water separation. Critical pressure boundary part under HTS 8402.90.00. High-strength carbon or alloy steel.
Boiler Expansion Joint
Expansion joints accommodate thermal growth between boiler pressure parts and structural steel during steam generation cycles. HTS 8402.90.00 covers these flexible connections. Refractory-lined slip or bellows type.
Boiler Manway Door Assembly
Manway doors provide access for boiler tube inspection and maintenance in steam generating pressure vessels. HTS 8402.90.00 boiler access component. Includes gasket, bolts, and davit assembly.
Boiler Feedwater Pump Impeller
Specialized impellers for multistage feedwater pumps deliver high-pressure water to steam boilers. While pumps may be 8413, boiler-specific impellers fall under HTS 8402.90.00. High-efficiency stainless steel design.
Deaerator Tray Stack
Tray stacks in deaerators remove dissolved oxygen from boiler feedwater, preventing corrosion in steam generating systems. HTS 8402.90.00 covers these water treatment internals. Stainless steel construction.
Boiler Firetube Replacement
A firetube is a critical heat exchanger tube used in fire-tube boilers to transfer heat from combustion gases to water, generating steam. It is classified under HTS 8402.90.00 as a dedicated part of steam generating boilers. These tubes are made from high-temperature resistant alloys to withstand boiler operating conditions.
Boiler Waterside Economizer
A waterside economizer preheats boiler feedwater using residual flue gas heat, improving overall efficiency of steam generating boilers. Recognized as a boiler part under HTS 8402.90.00 due to its integral role in vapor generation process. Typically constructed from finned tubes for optimal heat transfer.
Steam Drum Assembly
The steam drum separates steam from water in boiler circulation systems, essential for dry steam production in vapor generating boilers. Classified under HTS 8402.90.00 as a core pressure vessel component. Features internal baffles, dry pipes, and blowdown connections.
Burner Windbox Assembly
The windbox distributes combustion air to boiler burners, optimizing fuel-air mixture for efficient steam generation. HTS 8402.90.00 covers it as specialized boiler combustion system part. Includes dampers, supports, and refractory lining.
Boiler Superheater Tube Bundle
Superheater tube bundles increase steam temperature above saturation point, improving turbine efficiency in power generation boilers. Dedicated boiler part under HTS 8402.90.00. High-alloy construction resists creep at elevated temperatures.
Mud Drum for Water Tube Boiler
Mud drums collect sediment and sludge from boiler bottom circulation, preventing tube fouling in water-tube steam generators. HTS 8402.90.00 part for vapor generating boilers. Includes cleanout doors and blowdown valves.
Boiler Refractory Lining Kit
Refractory lining kits protect boiler pressure parts from combustion flame and hot gases in steam generating units. Specialized boiler insulation under HTS 8402.90.00. High-alumina castable mixes with anchor systems.
Downcomer Pipe Assembly
Downcomer pipes circulate unheated water from steam drum to boiler lower headers in natural circulation systems. HTS 8402.90.00 covers these dedicated circulation components. Heavy wall seamless construction.
Boiler Safety Valve
Safety valves automatically relieve excess boiler pressure to prevent explosion, mandatory for steam generating boilers. Classified under HTS 8402.90.00 as safety devices integral to boiler operation. ASME Section I certified.
Steam Generating Boiler Grate
Boiler grates support solid fuel bed and admit combustion air in traveling grate steam boilers. HTS 8402.90.00 part for fuel burning equipment. Heat-resistant cast iron or alloy construction.