Preformed Calcium Silicate Exhaust Duct Insulation

Molded half-sections for insulating hot gas exhaust ducts in petrochemical plants, leveraging calcium silicate's high-temperature performance. HTS 6806.90.00.20 applies to these sound/heat-insulating molded mineral articles.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳ChinaFree+35.0%35%
🇲🇽MexicoFree+10.0%10%
🇨🇦CanadaFree+10.0%10%
🇩🇪GermanyFree+10.0%10%
🇯🇵JapanFree+10.0%10%

Alternative Classifications

This product could be classified differently depending on its characteristics or intended use.

6812Lower: 10% vs 35%

If with asbestos reinforcement

Asbestos articles of mineral materials excluded to 6812 per chapter notes.

7308.90Lower: 10% vs 35%

If integrated into metal duct assemblies

Assembled with steel, classifies as metal structures in Chapter 73, not pure mineral.

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

Document custom molding dimensions to distinguish from standard boards

Comply with US fire safety standards (UL listings) for easier entry

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Molded Calcium Silicate Pipe Insulation

Pre-formed insulation sections designed to fit around industrial pipes, made from molded calcium silicate for high-temperature resistance up to 1200°F. Classified under HTS 6806.90.00.20 as articles of heat-insulating mineral materials specifically composed of molded calcium silicate, excluding those in headings 6811, 6812, or chapter 69.

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Fire-rated panels molded from calcium silicate for use in building partitions and protective enclosures in industrial settings. HTS 6806.90.00.20 covers these as sound/heat-insulating articles, distinct from ceramic or asbestos products.