Sourcing stock thickening machines from China

Zero duty, with classification by function

Heading 8439 covers machinery for making cellulosic pulp and for making or finishing paper or paperboard, plus parts. For a stock thickener, confirm whether the shipment is pulp-making machinery, a paper-making assembly or separately supplied parts. The table gives relevant categories, rather than interchangeable codes for the same machine.

Read from the UK Trade Tariff on 3 October 2026, all listed lines carried 0% duty for goods from China, with no anti-dumping or countervailing measures or suspensions recorded. The selected lines have no attached import controls. A separate suction-roll shell line carries a supplementary-unit import entry; if those shells are included, ask your customs broker to confirm the reporting requirement.

Give your broker the process description, drawings and separate parts list to confirm the commodity code. The paper-pulp pressure screens guide covers related stock-preparation equipment within the wider heading. Zero duty does not remove import VAT; see UK import duty and VAT.

Specify the stock and the thickening duty

State the fibre source, furnish composition, inlet consistency, target outlet consistency and dry-fibre throughput. Describe temperature, contaminants and the expected variation in feed. Agree a trial using representative stock, recording inlet and outlet consistency, filtrate solids, fibre loss, wash-water use and power consumption together.

Specify the thickener type, such as drum or disc, filter surface, mesh or cloth, wetted materials, seals and cleaning arrangement. Confirm feed and discharge connections, filtrate collection, installation space and access for changing filter media. Identify included pumps, drives, controls and replacement media so competing quotations cover the same equipment.

Complete new machinery placed on the Great Britain market must have CE or UKCA marking, a declaration of conformity and English instructions. If supplied as partly completed machinery, it must instead have comprehensive assembly instructions and a declaration of incorporation. Agree who handles integration into the stock-preparation line and the whole-line conformity assessment before ordering.

Worked duty example

Illustrative example, not a quote: Illustrative shipment of a compact paper stock thickening machine under 8439 10 00 00, invoiced at £28,000 free on board, with £4,000 of freight and insurance to the UK. The customs value is £32,000. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £32,000, so it is £6,400. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Stock trial: check output consistency and filtrate solids against the agreed acceptance criteria using representative pulp, rather than relying on a water-only demonstration.

Filter assembly: check mesh or cloth identification, drum or disc alignment, seals, scraper clearances and access for cleaning; look for rubbing, leakage and uneven drainage.

Drives and safety: check motor and gearbox identities, vibration, bearing temperature, guards, emergency stops and access interlocks against the agreed design.

Arrival and documents: check filter surfaces and shafts for transport damage, reconcile loose parts with the packing list, and match the machine identity to its conformity documents, English instructions and drawings. Use the inspection guide to plan checks.

What goes wrong

A thickener may handle the quoted liquid flow but miss the required dry-fibre output. Filter media can blind on the buyer's furnish, while an unsuitable mesh or leaking seal lets fibre escape into the filtrate. Outlet consistency can also vary when the trial feed differs from the mill's stock.

Unspecified wash-water demand, discharge arrangements or replacement filter media can disrupt installation and maintenance. Write the stock conditions, sampling method and acceptance criteria into the order, retain trial records and confirm spare-part drawings before shipment.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For machinery and equipment, see machinery imports.