Other
Other refractory ceramic goods (for example, retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and slide gates), other than those of siliceous fossil meals or of similar siliceous earths: > Other > Other
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 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 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(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
Products classified under HTS 6903.90.00.50
Alumina Crucible
High-purity alumina ceramic crucible used for melting and holding metals or chemicals at high temperatures in laboratory furnaces. Classified under HTS 6903.90.00.50 as a refractory ceramic good designed for extreme heat resistance, fired after shaping from inorganic nonmetallic materials. Meets chapter requirements for refractory applications beyond basic bricks.
Zirconia Nozzle
Zirconium oxide ceramic nozzle for continuous casting in steel mills, resisting molten metal erosion. Falls under HTS 6903.90.00.50 as other refractory ceramic goods, fired after shaping for high-temperature industrial use. Excludes non-fired or low-temp processed items per chapter notes.
Silicon Carbide Thermocouple Tube
Hexagonal silicon carbide tube sheathing thermocouples in kilns and furnaces up to 1600°C. HTS 6903.90.00.50 covers this refractory ceramic tube, fired from nonmetallic carbides, excluding electrical insulators. Essential for industrial heat measurement protection.
Refractory Ceramic Slide Gate
High-alumina slide gate plates controlling molten steel flow in ladle casting. Classified in HTS 6903.90.00.50 as other refractory ceramic goods (slide gates specifically mentioned), fired after room-temp shaping from oxide materials.
Magnesium Oxide Crucible
MgO ceramic crucible for rare earth metal melting, offering superior corrosion resistance. HTS 6903.90.00.50 applies to this fired refractory oxide vessel, distinct from basic brick forms.
Ceramic Retort Tube
Fired mullite ceramic retort tube for gas purification processes at elevated temperatures. Specifically listed under HTS 6903.90.00.50 as refractory ceramic goods for chemical reactions.
Refractory Kiln Plug
Cordierite ceramic plug sealing peepholes in pottery kilns, withstands thermal cycling. HTS 6903.90.00.50 for other refractory plugs, fired from clay-silica mixes.
Silicon Nitride Rod
Dense silicon nitride ceramic rod for thermocouple supports in molten aluminum holding furnaces. Refractory good under HTS 6903.90.00.50, fired nitride material excluding electrical uses.
Cupel Refractory Dish
Bone ash cupel for precious metal assaying in cupellation furnaces, absorbing base metals. Explicitly named refractory ceramic under HTS 6903.90.00.50.
Muffle Furnace Liner
High-temperature ceramic muffle lining protecting furnace chambers from contamination. HTS 6903.90.00.50 covers refractory muffles, fired after shaping.
Ceramic Bushing Support
Recrystallized alumina supports holding heating element bushings in high-temp electric furnaces. Refractory ceramic goods (supports named) in HTS 6903.90.00.50.
Refractory Ceramic Pipe
Silicon carbide reaction-bonded pipe conveying corrosive gases in petrochemical plants. Listed refractory (pipes) under HTS 6903.90.00.50, excluding non-fired articles.
Kiln Furniture Shelf
Cordierite kiln shelf supporting ceramic ware during bisque and glaze firing cycles. HTS 6903.90.00.50 for refractory supports and kiln furniture.
Graphite Oxide Nozzle Insert
Carbon-graphite ceramic nozzle insert for non-ferrous metal die casting. Refractory goods including graphite-based under HTS 6903.90.00.50 per chapter notes.
Refractory Ceramic Stopper Rod
Alumina-carbon stopper rod controlling molten steel pour from ladles in steelmaking. HTS 6903.90.00.50 other refractory goods (rods), fired composite ceramic.