From a purely mechanical standpoint, the task of the camshaft is to convert the rotary motion of the crankshaft into an oscillating motion of the cam follower by means of the cam profile. The shape of the cam profile defines the valve lift and is thus a fundamental adjustment parameter in the design of the gas exchange and thus of the combustion process.
MAHLE supplies customers worldwide with cast camshafts, steel camshafts that are forged or machined from solid material, as well as assembled camshafts. Blanks as well as ready-to-assemble components are manufactured in large-scale production runs. The great product diversity allows MAHLE to offer the right solution for every application. Manufacturing occurs exclusively in modern, fully automated production plants. This is how MAHLE guarantees consistently high quality.
For the production of cast camshafts, chilled cast iron is predominantly used. Cast camshafts with inductively hardened cam lobes meet the high requirements for rolling contact. In order to reduce weight, the shafts can be cast as hollow cylinders or profiles.
Casting production takes place in ultramodern, fully automated production facilities. A wide range of standard materials is available, as well as specialty materials for specific customer requirements. Modern machining centers and fully automated CBN grinders guarantee consistently high quality.
Advances in reducing friction and weight in the valve train have a direct influence on the efficiency of the entire engine, and thus on fuel consumption and CO2 emissions as well. The assembled camshaft from MAHLE has achieved a weight advantage of about 30 percent in its first series application in commercial vehicles.
In this case, MAHLE uses a special production process: using a thermal shrink-fit method, parts such as cam lobes, pulse-generator wheels, and drive input and output elements are joined to precision steel pipes with a high degree of torsional stiffness and flexural strength. The purely elastic transverse press fit guarantees a consistently high interference fit of the joined components over the entire service life. After all, the service life required of a commercial vehicle engine amounts to two million kilometers.