Sourcing motor parts, stators and rotors from China

A flat 2%

Read from the UK Trade Tariff on 27 September 2026, the parts of heading 8503 that we checked, including non-magnetic retaining rings, steel laminations and stator and rotor cores, and other parts of cast iron, cast steel or other materials, carried 2% duty on goods from China, with no anti-dumping measure. A few named parts for aircraft or particular vehicle motors have their own codes. Rotors with one or two magnetic rings on the inner side have 0% suspensions to 31 December 2028 on both the cast and the other line, and from 1 April 2026 laminations, cores and other parts used to make rotors for offshore wind turbines are 0% under authorised-use supervision. Several other listed parts are also 0% under suspensions to 31 December 2028: stators for brushless electric power steering motors (8503 00 98 33), small ferrite or neodymium rotors with a body 15 to 37 mm in diameter (8503 00 98 37), direct-drive washing machine stators of 206.6 mm internal diameter (8503 00 98 55) and small stacked stator bodies (8503 00 98 75). Within 8503 00 98 99 the suspension also covers listed parts such as steel motor housings of 35 to 65 mm inner diameter, stamped collectors up to 16 mm and stacked rotor bodies of 18 to 35 mm diameter, so check your dimensions against the tariff text.

Complete motors are in heading 8501, covered in the electric motors guide; carbon brushes are in 8545 and permanent magnets on their own in 8505. Confirm the commodity code.

Standards to write into the drawing

Parts sold to a motor maker do not carry UKCA marking of their own; the finished motor or machine carries UKCA or CE marking where required for the GB market. What the part needs is a drawing that names the standards. Non-oriented electrical steel for laminations is specified by grade under EN 10106, which fixes the maximum core loss for each grade and thickness, and rotor balance is specified as a balance grade under ISO 21940-11. Name the steel grade, lamination thickness, insulation coating, stacking method and balance grade on the drawing, and ask for the steel mill certificate.

Worked duty example

Illustrative example, not a quote: 5,000 stacked stator cores under 8503 00 20 90, invoiced at £20,000 free on board, with £1,500 of freight and insurance to the UK. The customs value is £21,500. Duty at 2% is £430. Import VAT at 20% is charged on the customs value plus duty, £21,930, so it is £4,386. Import taxes total £4,816; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £430 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Electrical steel: the mill certificate matched to the grade ordered under BS EN 10106, specific core loss and polarisation checked by the Epstein frame method of IEC 60404-2 on strip or by a ring test on sample stacks, and the interlaminar insulation coating checked by the surface insulation resistance method of IEC 60404-11.

Geometry: burr height measured on sampled laminations, stack height and compaction force checked, skew angle measured on skewed cores, bore roundness and concentricity measured on a coordinate measuring machine, and slot dimensions checked with gauges against the drawing.

Rotors and castings: rotors balanced to the grade specified under ISO 21940-11, magnet flux checked with a fluxmeter against the sample, bonded magnets pull-tested after a heat cycle, housings and end shields sectioned or X-rayed at the bearing seats for porosity, and laminations oiled or wrapped so they arrive free of rust.

What goes wrong

Motor parts fail on steel, burrs and balance. A cheaper electrical steel grade than the drawing raises core losses and heat, burrs left from stamping short adjacent laminations, and welded or cleated stacks distort so the bore is out of round. Rotors out of balance cause noise and bearing wear, magnets bonded with the wrong adhesive loosen when hot, and cast housings have porosity at the bearing seats.

Ask for the mill certificate and a core loss test on sample stacks, check burr height and stack height, measure bore roundness and concentricity, check balance on a sample of rotors against the specified grade, and pull-test bonded magnets after a heat cycle. Section a housing casting to check for porosity before bulk.

Cambridge China Bridge sources laminations, stator and rotor cores and motor housings, with drawings, steel grades and inspection agreed before tooling. See how our sourcing service works.

Related guides: Sourcing gearboxes and drive parts from China. For motor control equipment, see our motor control centres guide. For lubricants, see our guide to sourcing lubricants and motor oils. For terminal boxes, see our motor terminal box sourcing guide. For brush holders, see our motor brush holder sourcing guide.