Motor stator rotor lamination

The most critical factor is the grade of electrical steel (silicon steel). You should specify whether you require non-oriented (NO) or grain-oriented (GO) steel. For high-efficiency motors, look for low core loss (W/kg) and high magnetic permeability. Common thickness ranges from 0.2mm to 0.5mm; thinner laminations significantly reduce eddy current losses but increase production costs.

For high-volume production, Progressive Die Stamping is the industry standard due to its high speed and consistency. For prototyping or small batches, Laser Cutting or Wire EDM are more cost-effective as they eliminate the need for expensive tooling. For medium volumes with complex geometries, Compound Die Stamping offers a balance between precision and cost.

Laminations must be insulated to prevent short circuits. Common methods include C5 organic/inorganic coatings. For assembly, you should choose between interlocking (dimples), welding, cleating, or back-lap bonding (gluing). Back-lap bonding is increasingly preferred for high-performance motors as it minimizes vibration, reduces noise, and avoids magnetic interference caused by welding or interlocking.

Suppliers should adhere to ISO 9001 or IATF 16949 (for automotive applications). Critical tolerances include concentricity, perpendicularity, and stack height. Ensure the supplier uses CMM (Coordinate Measuring Machines) and optical projectors for inspection. The burr height must be strictly controlled (typically <0.02mm) to prevent insulation breakdown and ensure a high stacking factor.

Electrical steel prices fluctuate based on global raw material markets. It is advisable to lock in material prices at the time of order or use a price adjustment formula based on recognized indices. On Made-in-China.com, you can identify Audited Suppliers who have stable long-term contracts with major steel mills like Baosteel or TISCO to ensure price stability.

Clearly define tooling ownership in the contract; the buyer should own the die if they pay the Mould Fee. Ensure the supplier provides a guaranteed tool life (e.g., 1 million strokes) and covers routine maintenance costs. Request that the supplier stores the dies in a climate-controlled environment to prevent rust during transit intervals.

Laminations are highly susceptible to oxidation and physical deformation. Requirements should include VCI (Volatile Corrosion Inhibitor) paper or bags, vacuum sealing, and heavy-duty wooden crates with internal bracing. Ensure the pallets are fumigated (ISPM 15 compliant) to avoid customs delays in the destination country.

Request a factory video audit focusing on their stamping press capacity (tonnage) and annealing furnaces. Check if they have in-house tool design and repair capabilities. Use the secured payment services on Made-in-China.com to ensure that funds are only released after the Third-Party Inspection (TPI) confirms the technical specifications are met.