Sourcing pressure transmitters from China

Duty and mercury controls

Read from the UK Trade Tariff on 17 October 2026, the selected lines carried 0% duty for goods from China, with no recorded anti-dumping or countervailing duty and no suspension. Heading 9026 covers instruments measuring variables of liquids or gases. Electronic pressure transmitters fall within its electronic pressure-instrument line; the table also shows related liquid-level instruments, non-electronic pressure instruments and parts.

The pressure-instrument lines carry mercury import controls; the electronic and other pressure lines also carry mercury export controls. Unless an exemption applies, measuring devices containing mercury cannot be imported from China into Great Britain or sold there. Ask the factory to identify any mercury in the sensing assembly, particularly for melt-pressure models, and have your customs broker confirm the control and any claimed exemption before shipment.

Confirm the commodity code using the instrument's measuring function and construction. A transmitter sold for hydrostatic liquid-level measurement needs separate classification consideration. See the wider flow-meter and pressure-gauge guide for the rest of the heading.

Specify the pressure reference and process connection

State whether the transmitter measures gauge, absolute or differential pressure. Agree the measuring range, accuracy, allowable overload, operating temperature and compatible process fluid. Specify wetted materials, diaphragm construction, connection thread and sealing method. For differential models, identify the pressure ports and installation orientation.

Agree the output signal, supply requirements, wiring, connector and cable-entry arrangement. Request calibration results tied to each serial number, covering the working range with rising and falling pressure. Specify how zero and span adjustments will be controlled after calibration.

Electronic equipment liable to generate electromagnetic disturbance falls within the electromagnetic compatibility rules, subject to exceptions. Request model-specific conformity evidence. For transmitters intended for potentially explosive atmospheres, confirm the applicable equipment regulations with the relevant authority; check the declaration, equipment group and category, protection marking and any required certificate against the actual model.

Worked duty example

Illustrative example, not a quote: Illustrative batch of industrial electronic pressure transmitters under 9026 20 20 00, invoiced at £10,000 free on board, with £900 of freight and insurance to the UK. The customs value is £10,900. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £10,900, so it is £2,180. 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

Calibration: compare output with a calibrated pressure reference across the agreed range, in rising and falling pressure, and match the results to serial numbers.

Connections: gauge the ordered threads, inspect sealing faces and diaphragms, and check for leakage using the agreed test procedure.

Electrical operation: check connector pin assignments, polarity, output scaling and zero adjustment with the intended supply and receiving equipment.

Documents and identity: during inspection, match model labels, calibration records and hazardous-area documents; check the factory's mercury-content statement against the ordered construction.

What goes wrong

A gauge-pressure model supplied against an absolute-pressure specification gives misleading readings. Incorrect output scaling or connector wiring can make a sound sensor appear faulty. Threads that look similar may fail to seal, while a diaphragm or seal unsuitable for the process fluid can leak or deteriorate.

Calibration paperwork can describe a different range or serial number, and hazardous-area certificates can cover a different model. Approve a sample with the intended controller and pipe connection, then use the same acceptance checks for the shipment.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For components and parts, see sourcing for manufacturers.