Sourcing motor parts, stators and rotors from China

A flat 2%

Read from the UK Trade Tariff on 25 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.

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 does. 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.

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.