Sourcing ceramic thermocouple tubes from China
Ceramic thermocouple protection tubes classified under heading 6909 carry 4% UK duty from China across the relevant lines. Workplace supply duties include safe-use information and necessary testing. Confirm whether a refractory tube belongs under another heading. Cambridge China Bridge sources ceramic thermocouple protection tubes.
Duty on technical ceramic protection tubes
Read from the UK Trade Tariff on 1 October 2026, heading 6909 covers ceramic wares for laboratory, chemical and other technical uses, alongside certain agricultural and packing containers. This guide concerns protection tubes classified as technical ceramics. Refractory ceramic tubes are covered in our crucibles and kiln furniture guide, so confirm the heading before ordering.
The supplied tariff snapshot shows 4% duty from China on the relevant tube lines, with no anti-dumping or countervailing measure recorded. Listed suspensions concern specified products, including alumina balls and ceramic-carbon cartridges, rather than ordinary protection tubes. Confirm the commodity code using composition, hardness and intended use. The table repeats the residual code for different tube shapes. See the wider technical ceramics guide.
The tariff attaches an import waste control, plus waste export and cultural-object export controls. Waste shipment controls apply only when the material is waste. For used or discarded tubes from China, ask your customs broker to confirm the applicable import requirements before shipment. Ask the broker to check the export flags if you later export goods.
| Goods | Commodity code | Duty | Anti-dumping or countervailing duty on China |
|---|---|---|---|
| Porcelain thermocouple protection tubes | 6909 11 00 00 | 4% | None |
| Technical ceramic protection tubes with Mohs hardness equivalent to 9 or more | 6909 12 00 00 | 4% | None |
| Other technical ceramic protection tubes with a closed end | 6909 19 00 90 | 4% | None |
Specify the tube, bore and operating conditions
Specify ceramic composition and purity, density, porosity, overall length, outside diameter, bore diameter, wall thickness and straightness. State whether the tube is open-ended or closed-ended, including the tip shape, mounting details and clearance around the thermocouple assembly. Agree dimensional tolerances on a drawing rather than accepting a catalogue description.
Describe the operating temperature, heating and cooling pattern, atmosphere, process chemicals and any contact with molten material. Request batch material results and trial samples under your actual operating conditions. Workplace supply duties include safe-use information and necessary testing or examination. Obtain installation, heating and handling instructions that match the supplied material.
Worked duty example
Illustrative example, not a quote: 1,000 closed-end technical ceramic thermocouple protection tubes; illustrative only under 6909 19 00 90, invoiced at £16,000 free on board, with £1,500 of freight and insurance to the UK. The customs value is £17,500. Duty at 4% is £700. Import VAT at 20% is charged on the customs value plus duty, £18,200, so it is £3,640. Import taxes total £4,340; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £700 of duty. The import duty and VAT guide explains each step.
Inspection checklist
Material: match batch identification and composition, density and porosity results to the agreed grade; investigate substitutions.
Fit: measure the bore, outside diameter, length, wall thickness and straightness against the drawing; trial the intended thermocouple assembly.
Body and tip: inspect for cracks, chips, blocked bores and damaged closed ends; agree a suitable leak test where gas tightness matters.
Packing: check tubes are individually separated, cushioned and supported along their length; record damage and batch details on arrival. Use our quality inspection guide to prepare the inspection brief.
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What goes wrong
A nominally correct bore can narrow locally or become obstructed, preventing insertion of the sensor assembly. Bowed tubes may bind in the mounting. Thin or cracked closed ends can expose the sensor to the process, while a material substitution can shorten service life.
Rapid heating or cooling can crack a tube that survived a room-temperature inspection. Trial the material with the intended mounting and heating pattern before approving repeat orders. Long tubes can also break in transit when packing protects the ends but leaves the middle unsupported.
Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For own-brand ranges, see sourcing for brands.
Frequently asked questions
What is the UK import duty on ceramic thermocouple protection tubes from China?
For tubes correctly classified in the relevant heading 6909 lines, the supplied tariff snapshot shows 4% duty from China, with no anti-dumping or countervailing measure recorded.
Are all ceramic thermocouple protection tubes classified under 6909?
Do not assume so. The reference guide includes refractory tubes under heading 6903. Give your broker the material composition, properties and intended use before confirming the code.
What should I specify for a closed-end protection tube?
Specify the ceramic grade, bore, outside diameter, length, wall thickness, straightness and tip shape. Describe the operating atmosphere and heating pattern, and agree testing where gas tightness matters.
How do I check tubes before accepting a shipment?
Check batch material records, dimensions, bore clearance, straightness, cracks and tip damage. Inspect the packing and trial samples under your operating conditions before approving repeat supply.