Insulating Clay Refractory Blocks from Germany
Lightweight clay refractory blocks with insulating properties for boiler and incinerator construction, fired from shaped clay mixtures. HTS 6902.90.50.10 covers these as clay-based refractory blocks other than siliceous types. They minimize heat loss in high-temperature applications.
Duty Rate — Germany → United States
10%
Rate breakdown
9903.05.3910%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.97, articles the product of a member state of the European Union, with an ad valorem (or ad valorem equivalent) rate of duty under column 1 less than 10 percent, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include thermal conductivity test results (<0.5 W/mK typical) to substantiate refractory insulation claims
• Ensure packing lists specify 'fired clay refractory' to avoid scrutiny as unfinished goods
• Check for chrome content; if >10%, may require additional hazardous material declarations