Plastic Fantastic

DuPont has developed the first oil pan module for serial vehicle manufacture which will be used on Daimler’s 4 cylinder diesel engines, initially on the Mercedes C Class.

The company highlighted the engineering polymer breakthrough, for its Zytel 70G35 HSLR nylon, at this week’s Fakuma show. The 6 litre capacity oil pan comprises a die cast aluminium upper shell and multi functional lower shell made from the nylon.

The component, moulded by automotive supplier Bruss, offers a 1.1 kg weight saving over an entirely aluminium design and offers scope for further functional integration in future.

The pan involves a sophisticated sandwich design with a second injection moulded part welded onto the pan’s flat section. This design helps to calm the oil churned by the crankshaft while high ribs in the sump, which act as baffles, also help to achieve this calming.

The project involved close cooperation between DuPont and the moulder with finite element analysis techniques used to refine positioning of the ribbing, improving the stiffness of the critical flat section of the plan.

Flow studies carried out by DuPont showed the impact of wall thickness, gate number and positioning and weld line formation and warpage behaviour.

In fact, DuPont noted, the high flow rate of the Zytel enables one single gate to fill the mould cavity completely, resulting in reduced tooling costs and simplified process control.

Tests at DuPont’s technical centre at Geneva involved the combined engine and transmission “being dropped forcefully by a fork lift truck”. Real life tests at Bruss also confirmed the performance of the polymer-based component.