Fuel-saving potential of the commercial vehicle steel piston



Hanover, September 2012–Steel pistons have been used successfully in commercial vehicle for several years now. They became necessary because manufacturers wanted to fulfill the various stages of emissions legislation with measures inside the engine for as long as possible as power density increased. Consequently, peak cylinder pressures of over 220 bar can sometimes act on the piston, making the use of high-strength steel designs inevitable. New ways to make these pistons even more efficient are now being sought.

One significant untapped potential area in the engine crank mechanism is the reduction of the compression height of the piston. This allows longer connecting rods to be used, reducing friction losses by guiding the piston more efficiently. MAHLE expects fuel consumption savings of about one percent for commercial vehicles. For a commercial vehicle with consumption of about 30 liters/100 km and a service life of 150,000 km/year, this would correspond to savings of up to 360 liters of diesel fuel per vehicle per year. A piston of the typical commercial vehicle dimensions would also be about two kilograms lighter. If the connecting rod is also optimized, up to 30 percent weight savings can be achieved for the crank mechanism of a typical commercial vehicle engine.

A more compact piston that offers optimal cooling performance at the same time has previously been limited by production. MAHLE has now developed a new manufacturing method using a beam-based welding process that allows the necessary design flexibility. Initial principle studies have been very successful, and the beam-based joining method is now being developed into a mature process. This means that MAHLE will soon be able to provide its customers with the most innovative piston technology to meet anticipated future requirements.

The MAHLE Group is one of the 30 largest companies in the automotive supply industry worldwide. With its two business units Engine Systems and Components and Filtration and Engine Peripherals, MAHLE ranks among the top three systems suppliers worldwide for piston systems, cylinder components, as well as valve train, air management, and liquid management systems. MAHLE’s industrial activities are combined in the Industry business unit. These include the areas of large engines, industrial filtration, as well as cooling and air conditioning systems. The Aftermarket business unit serves the independent spare parts market with MAHLE products in OE quality. In 2011, the MAHLE Group generated sales of approximately EUR 6 billion; around 49,000 employees work at over 100 production plants and eight research and development centers.

Further queries:
Ruben Danisch
Corporate Communications/Public Relations
Pragstrasse 26–46
70376 Stuttgart
Phone: +49 (0) 711/501-12199
Fax: +49 (0) 711/501-13700