Fused Silica Capillary Tubes
Thin-walled, unworked capillary tubes of fused silica used primarily in gas chromatography and analytical instruments. These tubes maintain optical clarity and purity essential for precise measurements. HTS 7002.31.00.00 covers them as unworked tubes of fused quartz or other fused silica.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If fused silica content <60% SiO2 or contains alkaline oxides
Lower purity fused products may classify as laboratory glassware rather than pure fused silica tubes.
If for tubes of glass other than fused quartz/silica
Standard borosilicate capillary tubes fall under other unworked glass tubes.
If sold as complete chromatography columns with stationary phase
Assembled analytical columns are valves/appliances, not raw tubing.
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
• Include dimensional specs and SiO2 purity certificates; capillaries under 1mm ID often scrutinized for microsphere confusion
• Declare as unworked even if coiled for shipping—uncoiling doesn't constitute working per chapter notes
Related Products under HTS 7002.31.00.00
Fused Quartz Semiconductor Processing Tubes
Long, unworked tubes of fused quartz used in semiconductor diffusion furnaces and CVD reactors. Their extreme purity prevents contamination during wafer processing at high temperatures. Falls under 7002.31.00.00 for unworked fused silica tubes.
Fused Quartz Optical Fiber Drawing Tubes
Precision unworked tubes of fused silica used in optical fiber preform collapse and drawing towers. Their clarity and low impurity levels are critical for single-mode fiber production. HTS 7002.31.00.00 applies to these unworked fused quartz tubes.
Fused Quartz Solar Simulator Tubes
Unworked fused silica tubes serving as test chambers for photovoltaic cell evaluation under concentrated solar simulation. High solar transmission (down to 200nm) maintained through purity. HTS 7002.31.00.00 for unworked tubes of fused quartz.
Synthetic Fused Quartz Process Gas Tubes
Unworked synthetic fused silica tubes for delivering process gases in semiconductor and solar cell manufacturing. Flame-polished ends acceptable if pre-annealing per chapter notes. HTS 7002.31.00.00 covers these unworked tubes.
Fused Quartz Tubing for Laboratory Reactors
Unworked tubes made from fused quartz or fused silica, supplied in straight lengths without further processing beyond forming and annealing. These tubes are essential components in laboratory equipment like reactors and distillation apparatus due to their high thermal resistance and chemical inertness. Classified under HTS 7002.31.00.00 as unworked tubes of fused quartz or other fused silica.
Fused Silica Thermocouple Protection Tubes
Unworked protective tubes for thermocouples in high-temperature environments like glass melting tanks. Made from pure fused quartz to withstand molten glass contact without devitrification. Classified in 7002.31.00.00 as unworked tubes of fused silica.