Around the world millions of passenger cars are on the road every day. But the regulations in other countries to govern the quality of fuel are seldom as strict as in Germany. In order to ensure that products “Made in Germany” can also withstand the most difficult operating conditions, Lukas Bock, design engineer and project manager at MANN+HUMMEL, has developed a new and revolutionary version of the conventional pressure regulation valve. The magic word is RobustPlus, a material free of elastomers which is able to withstand even the highest loads. In an interview the engineer reveals details of the development process at MANN+HUMMEL.

Mr. Bock, why was it necessary to develop a pressure regulation valve with the RobustPlus membrane?

Lukas Bock: “The important point here is that our existing pressure regulation valve was manufactured using an elastomer membrane. But there were problems with this material on the Chinese market due to chemical degradation of the elastomer. The aggressive nature of the fuel used unfortunately caused the material to harden and develop cracks. The consequences were, for example, an engine oil leak or an uneven engine idle. The problem, however, only occurred with certain gasoline engines. The question of whether the membrane would even fail depended on the type of engine and operating conditions.”

Are there other countries where the fuel quality is worse than in Europe?

Lukas Bock: “The market where our invention is most needed is of course Asia. The fuels used there as already mentioned are partly of an inferior quality, which is also due to substandard mixtures. But this is also true for South America and partly also for the USA. These are all countries where the quality of fuel can fluctuate. ”

engineer and project manager at MANN+HUMMEL

Lukas Bock, design engineer and project manager at MANN+HUMMEL

This is a good enough reason to develop a stable and robust pressure regulation valve. What exactly are the advantages of the new version with RobustPlus?

Lukas Bock: “Now there are no more problems with material degradation caused by chemicals. We have performed numerous tests in our laboratories. The result is that the new version of the pressure regulation valve is also able to withstand undiluted acids and nothing happens to the diaphragm. Our vision was to develop a pressure regulation valve which is completely free of elastomers. The solution we found uses a fully fluorinated polymer. The material is not a form of rubber, but rather a thermoplastic substance. It convinces with its resistance to chemicals and mechanical durability.”

The durability of RobustPlus has been verified by extensive tests. But please could you say something more about the development and test phase of the new pressure regulation valve.

Lukas Bock: “The actual project started at the end of 2014 and ran until the end of 2016. During the development phase we changed the design of the membrane a number of times to arrive at the best possible version. The development was concluded with a B sample design. We arranged for the manufacture of injection molding tools and then tested these. At the end of 2016 the product passed all of our tests, even under test conditions which were excessively severe. The test results were partly above the requirements by a factor of ten.”

That sounds really impressive! Have any automobile producers shown interest in the product?

Lukas Bock: “We used the past year to introduce this new product to different customers and also to supply some manufacturers with A-samples. In September 2017 we presented the new pressure regulation valve with RobustPlus for the first time at the Frankfurt motor show. At the end of the year, we were able to win the first mass production order.”

Can you also imagine using RobustPlus for other MANN+HUMMEL products?

Lukas Bock: “Naturally! Up to now we are the only manufacturer able to offer the material in this form. We are therefore working on the possibility of also transferring the advantages of RobustPlus over to other products. For the time being RobustPlus represents the newly developed pressure regulation valve. But it would of course make sense to exploit the durability of this material in other products.”

Mr. Bock, thank you for the interview!