A development partner par excellence — Krämer+Grebe sets new standards in the tool design for cylinder heads
Mannheim – Biedenkopf Wallau July 21, 2018. There is always a first time, just as recently happened in the history of the foundry Mannheim of the longtime client Daimler AG. In order to meet the highest quality criteria and at the same time produce very efficiently, for the first time a completely new tool concept was developed in cooperation with a development partner instead of building on a tried and tested one. The tool should serve the new cylinder head core production of the 10.7L to 15.6L heavy-duty engine platform (HDEP) engine generation. Together the partners have now created a double-beam core mould which not only sets new standards in design and quality but at the same time significantly reduces the total cost of ownership (TCO).
Since decades already the leading companies have been working together on prototype developments. And even though core mould tools are always regarded as a ‘matter of course’, they are very much essential for the manufacturing of innovative products with qualitative excellence. Especially when it comes to quality standards, compromises are not an option – it is only “The best or nothing” according to the in-house motto. In order to fulfil these challenges of toolmaking, the company was looking for a partner with whom it could independently develop an innovative tool concept that would meet all of the company’s own standards and the highest demands in subsequent production. As a long-standing trusted partner for the tool production of cylinder heads, among other things, eventually, the mould and toolmaker Krämer+Grebe fully convinced. Particularly due to their maximum flexibility, the use of the latest technologies, simulation and production methods, an extremely tight timeline and a highly demanding development loop, Krämer+Grebe was the perfect partner for a development project of this scale.
While in 2015 first considerations were made, a year later already, in late summer 2016, the go-ahead was given for the joint project to develop a completely new and more efficient tool concept. The starting point was the existing single-core cylinder head mould. From there special features of the new concept should include double engraving, ease of maintenance, functionality and robustness. By means of FEM calculations, in particular, the latter could be guaranteed. A specific focus during the tool design was also placed on stress reduction and minimisation of deflection, as well as the analysis of various load cases, such as shooting head and load carrier. The highlights of the entire development process were comprehensive core process simulations in several development loops, which made it possible to redefine bullet holes, ejection and venting at an early stage of the process. Overall, the tool concept is now optimised in such a way that it has an extremely positive effect on maintenance, lifetime and repairs. This is of great importance for the new concept, as it extends the production cycles, significantly reduces the amount of amine required as well as the original tool weight by 600kg.
An equally faithful process companion throughout the entire concept development and of high importance for the final construction was the decisive criterion of minimising the TCO. According to Katrin Grebe, managing director of Krämer+Grebe, an essential point within every development process, still a truly holistic and early focus is often considered too rarely. Therefore, among other things, also the philosophy of using standard parts in such developments is crucial for its success. This represents not only a considerable cost factor but also increases the ease of maintenance.
Due to the overall complexity and amount of demands towards the new tool concept, hence it is no surprise, that the cooperation between the two companies built on a maximum level of trust and continuous exchange of experience. As a result, for example, the tool was directly adapted to the “State of Art Technology” in order to achieve the best possible production performance.
On July 24, 2018, the innovative double girder core mould was officially handed over to the foundry in Mannheim and therewith completed to the fullest satisfaction of both companies. But what significance does this step actually have in retrospect for the companies and the industry? Together they not only created an innovative and efficient core mould for the HDEP cylinder heads, but have taken it a further and far-ahead step towards a technological future. All of this would of course not have been possible without the valuable exchange of experience with Krämer+Grebe. A partner that completely convinced throughout the process and was once again able to prove the unique performance they accomplish as a development partner. And eventually what counts the most is: only together we are strong. Thus it was possible for both parties to develop a tool concept that not only makes every foundry heart beat faster but above all sets new standards. We can therefore already be excited about future projects of this development partnership.
Three exciting and eventful trade fair days in Nuremberg have come to an end. When EUROGUSS wrapped up on 18 January 2018, its visitor numbers set a new record. Despite snow, rain, strong winds and the traffic chaos that came with it throughout large parts of Germany and Europe, 15,000 trade visitors still made their way to Nuremberg for the die-casting trade fair.
Once again, Krämer+Grebe was able to win visitors over with its visionary thinking and high level of quality. Not only were existing business relationships with customers and partners maintained and strengthened, but new national and international contacts were also established. EUROGUSS serves as a particularly excellent platform for personally getting to know one another. All told, the 2018 trade fair was another great success!
A key subject that Krämer+Grebe considers to be a high priority – and was therefore presented at the trade fair – is conformal cooling in tools, which is made possible by additive manufacturing. The simulations show that, for example, about 30% less time can be required for solidification. An informative showcase with sample parts and simulation results was very well received.
A complex cavity of the BMW I01 support structure also showed that Krämer+Grebe is well equipped for very heavy die-casting moulds with high requirements.
Market leader General Motors relies on the experience and know-how of the German toolmaker Krämer+Grebe as well as the foundry company Halberg Guss for the engine block production of the Sierra Duramax 2500HD.
Last month was once again time to shine for the stars of the car industry at the NAIAS 2018 in Detroit. While one would assume that by now the overall trend at a fair, as important as this one, represents the movement towards electric cars, the hype about full-size-trucks continues momentously. So, no surprise that the main producers Ford, Chevrolet and GMC showcased their innovative truck highlights and newcomers – with no electric super-truck yet to come. Instead they surprised with diesel engines like the GMC V8 Duramax being one of the engine highlights for truck lovers and convincing with 450 HP, 6.6 L and a towing capacity up to 10 t in form of the Sierra Duramax 2500HD.
Whereas this engine is of great interest by being the growling heart of the full-size pickup, only little people know more about it than just the performing hard facts. Still there is always a beginning to every story, and the production story of the V8 Duramax begins in Biedenkopf-Wallau, Germany, in the engineering department of Krämer+Grebe.
The high-tech toolmaker is renowned in the industry for their longtime know-how and the resulting high quality. “Besides already the fact that we’re talking about a powerful V8 engine, the main issues in the production of the casting tool for the V8 Duramax were: lightweight design, sand reduction, suitability for mass production & automation, process reliability and last but not least maintainability.” says Katrin Grebe, CEO at Krämer+Grebe. So for the V8 Duramax they made it their task and challenge to develop a core package concept for the most economic casting
process, while keeping the focus on designing it more cost efficient by reducing the amount of sand used in the process of core shooting. Especially as the costs of recycling contaminated sand are enormous and the high waste of a natural resource simply not sustainable. The goal was to reduce a significant amount of sand through realization of the shellthickness for the cores of approx. 15-25mm., which eventually led to the result of an incredible reduction of 40% around 70kg sand, compared to an American toolshop, for every single casted engine.
Mainly due to downscaling the use of sand and therefore the cost in production, Krämer+Grebe made it economically interesting for Halberg Guss and GM to manufacture the engines in Germany. This is where the story of the V8 Duramax continues: in fact at Halberg Guss, one of Krämer+Grebe long trusted partners and the market & technology leader when it comes to the production of engine blocks. According to Juergen Schwan Sales Director at the Saarland casting company: “it was the perfect mix of costs, quality and timing” that made both companies the perfect fit for the V8 Duramax project. With a developing time of 4-5 months only, Krämer+Grebe could easily outstand its competition, not to say by its quality and competence during prototyping and production. Same accounts for Halberg Guss and what they produce in precise coordination is the heart of the engine – a full cast part weighing 145kg – and produced with a capacity and logistics of some 100.000 pieces per year.
Until the finishing of the full-size pickup the story keeps going from the engine assembly at Duramax to the car assembly of GMC in Detroit, USA – where the engine blocks get their horse powers and the American dream of a car its face. And before the trend of electronic cars doesn’t rule the American market, the German casting companies will remain first choice in qualitative casting tools & engine block production.