Achieving more with less

Saving resources has top priority.

When you think of the dimensions of a LEXION 780 combine harvester – 11 meters long, 4 meters high and weighing 18 tons – your first thought usually isn’t weight optimisation. But just like any self-propelled machine, it all comes down to resource conservation, especially with combine harvesters weighing many tonnes. After all, every kilogramme that has to be moved ultimately has an impact on fuel consumption and the pressure exerted on the ground. Here, every kilogramme that can be saved, counts.

What’s more, weight-optimised structures also save resources in their production because less material is needed. It doesn’t take long until an intelligently constructed component pays off. Together with CLAAS, Pentas has developed a process for constructing fuel tanks with significantly reduced wall thickness without losing the necessary stability.

Despite their lightweight construction, components made using the rotational moulding process meet all requirements, standards and legal regulations.


Every gram counts.

Even with machines weighing 18 tons.

Zelfs bij 18 ton machinegewicht.

Trimming the tank: Using a range of measures to reduce wall thickness, it was possible to lower the weight in some tanks by up to 20% without any significant loss in stability.


Through thick and thin.

In our efforts to reduce material, safety always has top priority.

The fuel tanks of a CLAAS combine harvester can hold more than 1000 liters. Bearing in mind that it only takes one drop of diesel to contaminate several hundred liters of water, a full tank of fuel doesn’t just carry a lot of weight, it also carries a lot of responsibility. This is why in every effort to reduce weight, safety must come first. When it comes to product development for fuel tanks, it requires a partner with experience in construction and production. And that’s exactly what CLAAS has found in PENTAS.


A quarter less weight.

After 36 months of intensive development work followed by successful TÜV certification, in July 2018 PENTAS introduced a new tank system for CLAAS combine harvesters. The system, which consists of an approximately 950-litre main tank and a 200-litre additional tank, is 25 percent lighter than its predecessor. Even with this optimisation, the new tank system still fully meets all requirements it is subject to in terms of service life, stability, and safety. This new construction has succeeded in reducing the weight of the tank system as well as the associated product costs at the same time.


For the new system, engineers from PENTAS worked together with CLAAS to come up with a topology optimisation. In real terms, this means that certain parts of the tank where the most pressure builds up have higher wall thickness than other areas of the tank.


The construction drawings for the tank, adapted to the respective requirements and spatial conditions of a machine, were done using FEM calculation (Finite Element Analysis). This computer simulation shows all critical areas in a tank, which arise due to a variety of conditions, and serves as the basis for the topology optimisation.

Finite Element Analysis of a tank with low wall thickness. The red areas show the critical sections where wall thickness should not be reduced.


The topology optimisation that results from the the FEM is then used in the tool design for the new tank. This ensures that the only the critical sections of the component are given thicker walls. This results in a considerable material and weight savings without having to comprimise stability or safety.


Simulation of the new component with additional reinforcements.


Cross section of the different wall thicknesses.


The new tank system with reinforcements.