Cleaning Challenges of New Energy Motor Housings

1. Complex structure with numerous enclosed dead zones hard to reachThe housing is equipped with spiral water cooling jackets, narrow water channels, intersecting oil passages, deep blind holes, threaded holes and bearing shoulders. The flow channels are narrow and interconnected. Ordinary spraying and air blowing only clean outer surfaces and can hardly reach interlayers and the root of intersecting holes, where aluminum chips and burrs tend to get trapped, forming high-risk blind cleaning areas.

2. Diverse contaminants with strongly adherent micro debrisContaminants include die-casting release agent film, high-viscosity cutting fluid, micron-scale aluminum powder, root burrs and die-casting dross. Fine aluminum chips easily lodge in thread roots and gaps. Even after being loosened by soaking or ultrasonic cleaning, debris may re-adhere to cavity walls. Degreasing alone cannot remove chips and burrs.

3. Sensitive aluminum alloy material with low process toleranceAluminum is soft and chemically active. Excessive pressure or improper nozzle distance may scratch bearing shoulders and sealing mating surfaces. Improper pH of cleaning agents or residual moisture may cause oxidation discoloration and pitting corrosion. Hard cutting tools for deburring will generate secondary debris, threatening insulation and cleanliness.

4. Stringent OEM cleanliness standards with traceability requirementsIt follows particle classification control per VDA19 / ISO16232. Contaminants must be inspected by particle extraction, weighing and endoscopy instead of visual check only. Stable consistency is required for mass production. Cleaning parameter logs must be saved to meet automotive quality traceability requirements. Manual cleaning suffers from poor consistency and high omission rate.

5. Difficult drying and high risk of residual water in deep cavitiesIt is hard to remove residual water from water jackets and deep blind holes by conventional hot air drying. Remaining moisture may lead to aluminum corrosion, watermarks and poor insulation during subsequent assembly. Ordinary air knives cannot fully drain trapped water in interlayers and hole bottoms.

6. Demands on production tact time, product changeover and automation compatibilityMultiple types of motor housings share the same production line with different cavity and hole layouts, leading to tedious fixture commissioning. The equipment needs to support robotic loading/unloading and integrate into automated lines between CNC machining and leak testing. It must finish deburring, cleaning, rinsing and drying within required tact time while balancing throughput and yield.

7. Difficult control of circulating water filtrationContinuous generation of aluminum chips easily clogs filters. Insufficient filtration capacity will cause secondary contamination by recirculating dirty water, resulting in unstable cleanliness.