ClassA Motor

Raw material

Aluminium Extruded Housing

Billet heating & extrusion → Stretching, cutting & ageing → CNC machining → Anodizing

✓ Expert reviewed All content on this page has been reviewed by a senior motor engineer.

Process flow

4 main process steps, with the equipment and instruments used at each step, their main suppliers, and the technical control points.

  1. 1

    Billet heating & extrusion

    6063 billets are heated and extruded through a die into the square housing profile, quenched at the press.

    ⚙ Aluminium Extrusion PressAutomated
    International
    UBE MachineryGuangzhou, SMS group
    Mainland China
    TYHI

    Technical control points:

    • ▪Billet and die temperature — Billet about 450–500 °C; die about 430–480 °CCheck: Pyrometers; every billet
    • ▪Exit temperature and press quench — Exit ≥ 500 °C, then fan / water quench for full T5 responseCheck: Pyrometer; continuous
    • ▪Profile dimensions and twist — Per GB/T 14846 / EN 755-9 and drawingCheck: Gauges; first length and periodic
  2. 2

    Stretching, cutting & ageing

    Profiles are stretched straight, cut to length and artificially aged to T5.

    ⚙ Ageing OvenAutomated
    International
    To be added
    Mainland China
    To be added
    ⚙ Hardness TesterTest instrumentSemi-automaticManual
    International
    To be added
    Mainland China
    To be added

    Technical control points:

    • ▪Straightness — Per GB/T 14846 / EN 755-9Check: Straightedge; sampling
    • ▪Ageing — About 185–205 °C for 2–6 hCheck: Oven recorder; every batch
    • ▪Hardness — 6063-T5 ≥ 8 HW (Webster)Check: Webster hardness tester; every batch
  3. 3

    CNC machining

    Spigot, bore, mounting holes and slots are machined.

    ⚙ CNC Machining CentreAutomated
    International
    MazakGuangzhou, OkumaGuangzhou, DMG MORI
    Mainland China
    MinjiaGuangzhou, Haitian Precision
    ⚙ CMM, Roundness & Runout GaugesTest instrumentSemi-automaticManual
    International
    MitutoyoDongguan, HexagonGuangzhou, MarpossShenzhen+1 more →
    Mainland China
    To be added

    Technical control points:

    • ▪Bore and spigot concentricity — ≤ 0.02–0.03 mm (affects air gap uniformity)Check: CMM; first article and SPC
    • ▪Hole positions — Per drawing, typically ±0.05 mmCheck: CMM / gauge; first article and periodic
    • ▪Burrs and chips — NoneCheck: Visual; 100%
  4. 4

    Anodizing

    Parts are anodized (and optionally dyed) for corrosion protection and appearance.

    ⚙ Anodizing LineAutomatedSemi-automatic
    International
    To be added
    Mainland China
    To be added

    Technical control points:

    • ▪Film thickness — 8–15 µm (e.g. AA10)Check: Eddy-current gauge (ISO 2360); every batch
    • ▪Colour consistency — ΔE ≤ 1.5 versus master sampleCheck: Colorimeter; every batch
    • ▪Sealing quality — Passes dye-spot / admittance test (ISO 2143 / ISO 2931)Check: Seal test; every batch

Incoming inspection & approval tests

  • Dimensions and geometric tolerances (bearing seat, spigot)CMM measurement
  • Internal porosity of castingsX-ray inspection
  • Anodizing thickness and salt sprayISO 2360, ISO 9227
  • Material compositionSpectrometer analysis

Buyer FAQ

Extruded or die-cast housing?
Extruded housings (6063-T5) are dense, cheap to tool and come in any length, which suits square-flange servo, stepper and BLDC motors. Die-cast housings allow integrated feet, bosses and complex shapes but need costly dies and porosity control.
Which dimensions are critical?
Bore diameter and roundness (the stator fit), concentricity of both spigots with the bore, and end-face perpendicularity. These set the air gap and bearing alignment.
How is the stator fixed in an aluminium housing?
Usually by heat-shrinking (housing heated to about 150–250 °C) or press-fitting, sometimes with adhesive. Check the interference at both minimum and maximum operating temperature, because aluminium expands about twice as much as steel.