Mechanical Technology January 2016

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Mechanical Technology — January 2016 33
⎪ Structural engineering materials ⎪
The world’s first thermoplastic oil tank for dry sump engines has
been developed by Hummel-Formen, a brand by ElringKlinger
AG at Lenningen, Germany. The reservoir, which weighs around
2.6 kg, is made from Ultramid® A3WG7, a BASF polyamide
66 with 35% glass fibre reinforcement, which is resistant to oil and
thermal aging.
The tank is 59% lighter than previous steel or aluminium welded
constructions and has an improved, multi-functional oil separation sys-
tem integrated into the tank. The complex component is used in the new
Mercedes-AMG GT, which has been available since spring 2015.
The oil reservoir is noted for its ingenious geometry. It comprises ten
different, injection-moulded polyamide parts, which are joined together with
13 further elements such as sensors, sieves, covers and screws to form
a single component – manufactured using vibration welding and various
snap-in mechanisms.
By optimally using the space available, a lot of different functions could
be integrated. The component deals with the ventilation of the crankcase
– including oil separation – makes possible the filling and changing of the
oil as well as controlling the oil level and its quality. It also slows down
and roughly filters the incoming oil.
“With the new oil tank made from BASF plastic, we are not simply re-
modelling previous aluminium welding designs,” says Thomas Wolf, head
of technical sales at Hummel-Formen. “We have optimised the structure
of the component in such a way that it is now lighter, quieter and more
compact. The refined internal structure, with various elements and func-
tions for integrated oil separation, would not have been possible if metal
had been used,” he adds.
The development work, from the 3D model through to the first functional
samples made with silicone moulds, took 12 weeks, while the production
of the first parts made with serial moulds took about a year.
The success of this engineering effort provides, among other things,
better driving dynamics for the Mercedes-AMG GT: the vehicle has a lower
centre of gravity, therefore sits better on the road and reaches higher speeds
around bends.
In contrast to pressure lubrication, which is normally used in car engines
and works with an oil pan, dry sump lubrication originates from motor rac-
ing: where the oil pan is replaced by a separate tank with a tall and narrow
design. The oil tank is configured so that the pressure oil pump is always
able to reliably suck in the oil even in extreme driving situations, such as
driving around bends at high speed or heavy braking. q
Thermoplastic oil tank for dry sumps
A dry sump tank with improved integrated oil separation has been developed and
manufactured by Hummel-Formen for the new Mercedes-AMG GT.