New at MAHLE: solid-metal, machined, and composite commercial vehicle camshafts
Stuttgart, September 2008—MAHLE provides casted, composite, and forged camshafts for passenger car engines, either as raw parts or ready-to-assemble. For commercial vehicles, MAHLE is already producing cast camshafts. The commercial vehicle portfolio is now being expanded to include composite camshafts and steel camshafts manufactured from solid metal.
The MAHLE composite camshaft allows, for one thing, a reduction in weight of up to 50 percent; for another, it enables the integration of additional functions such as camshaft oil separation or counterbalance shafts. It consists of a precision steel tube onto which the cams and parts are attached with a thermal shrink fit. This transverse press fit provides high durability—as do the carefully selected materials. For commercial vehicles, MAHLE exclusively uses cam lobes made of inductively hardened ball bearing steel 100Cr6, which allows contact stresses of about 2,000 MPa.
The selection of different materials for the composite camshaft allows targeted applications. Components that are subject to lower loads are made of less expensive materials. For example, the trigger wheel is often a power metal or sheet metal part, the axial bearing rings are made of low-alloy steel, and the drive wheel is a forged part, while the cam lobes are made of high-alloy steel.
A further advantage of the composite camshaft from MAHLE is the ability to integrate additional functions into the camshaft tube. For example, the swirl generator of a blow-by separator, which combines high separation rates with a reduced freezing hazard and low space requirement. MAHLE has also already created an integrated counterbalance shaft for a V6 engine for commercial vehicles. It is based on the patented MAHLE CamInCam® technology.
For a year now, MAHLE has also provided its customers with steel camshafts manufactured from bar stock. These are used mainly in commercial vehicle, stationary, and large engines. For commercial vehicle engines, they are used primarily as a central camshaft with tunnel bearings, which is still a low-cost solution for the highest requirements for bending and torsional stiffness.
Large engines have similarly high requirements. In addition, a service life of up to 60,000 operating hours must be guaranteed there. For large engines, segmented camshafts are used. Each segment contains the cam for at least one cylinder and is screwed end-to-end to the adjacent elements. The product range currently includes camshafts with an overall length of up to 2.15 m, and diameters up to 35 cm.
MAHLE is thus a complete provider of camshafts for motorcycles, passenger cars, commercial vehicles, and stationary engines, and is the only supplier that covers the entire spectrum of camshafts for all types of combustion engines.
The MAHLE Group is one of the 30 largest companies in the automotive supply industry worldwide. As a leading manufacturer of components and systems for the combustion engine and related products, MAHLE ranks among the top 3 systems suppliers for piston systems, cylinder components, valve train systems, air management systems, and liquid management systems. MAHLE employs around 48,000 people at 110 production plants and eight research and development centers. In 2007, MAHLE achieved sales of over EUR 5 billion (USD 7.5 billion).