The challenge
Keeping your taxis on the road
An Australian-made transmission found in most taxis had a reputation for not going the distance. The problem was at the heart of the unit – an aluminium alloy casting known as the ‘clutch cylinder’.
The unit would suffer a fatigue failure at about half its rated lifetime – the taxi would be off the road, and the transmission would need a rebuild.
Many casting companies had attempted to make a better version of the part without success and the transmission was getting a bad reputation.
Our response
Working with Nissan Casting Australia
We worked with Nissan Casting Australia to redesign the part and tooling to make it suited to their Low Pressure Die Casting (LPDC) process.
We used our knowledge of the LPDC process to propose various designs that were then analysed with the MAGMAsoft flow and solidification simulation program. With the predictions looking good, the investment was made in the new tooling and ancillary equipment.
We then worked as part of the in–plant team during the commissioning phase, collecting data and reconciling it with the simulation model – all with the aim of tuning the process to get the best result.
The results
A new casting process, a fundamental fix
The results for the LPDC version of the clutch cylinder casting have been excellent. Not only do the finished components meet the required fatigue life for the first time, but wastage of reject parts is also reduced.
Another benefit is that much less metal needs to be poured to produce the component, meaning less energy is consumed.
With an annual production in excess of 200,000 parts, the conversion to LPDC has made a substantial positive impact to the triple-bottom-line: for both the caster and the transmission maker.