1. The Manufacture of Aluminium Alloy Wheels

2. Aluminium Alloy Wheels These are produced in a wide range of sizes and designs.

3. Some Examples

4. Production Flow Furnace Press 1 Press 2 Water bath X-ray station Machining and painting robot store A mix of new alloy and recycled wheel is introduced to the Furnace, and the Robot transfers charges to each Press and unloads each in turn to the Water Bath. The wheels are inspected before Machining and Painting.

5. Process Flow in More Detail

6. Some Problems with Product defectPorosityInclusionsOverfillShrinkageOthers Frequency24141289486410534 percentage47259810 Cumulative percentage47728290100 Need link to ‘porosity index’ which is used later

7. Some Possible Causes POROSITY mould type painting temperature lubrication cleaning mould strip manipulation cleaning manual work instructions method machine prime material pressure fill time cycle speed pressure time supplier % recycle type degassing quantity type deoxidant quantity temperature

8. What to Investigate? FACTORSPOSSIBLE LEVELS PressA Press APress BBoth painting mouldBType AType B (1)(2) mould temperature C620640660680700 injection pressureD8008509009501000 recyclingENo (0)Yes (1) degassingFNo (0)Yes (1)

9. Current Settings PressBoth Painting mouldType A Mould temperature640°C Mould pressure900 kg/cm 2 RecyclingYes (20%) DegassingYes With these conditions, the mean porosity index (average of ten tyres) is 3.65

10. 3.5 3.6 3.7 3.8 0102030405060 3.6538 3.7809 3.5267 Porosity Index with standard settings Rows C8

11. Best Settings (after DoE) PressBoth Painting mouldType B Mould temperature660°C Mould pressure1000 kg/cm 2 RecyclingYes (20%) DegassingNo With these conditions, the mean porosity index (average of ten tyres) is 2.46

12. 2.3 2.4 2.5 2.6 2.7 0102030405060 2.461 2.5987 2.3233 Porosity Index with best settings Rows C8