Valve trains for commercial vehicles

In order to further optimize the efficiency of the combustion engine in commercial vehicles, MAHLE has developed a new valve train system that supports variable valve timing. MAHLE has integrated functions such as engine braking, exhaust gas temperature management, and reduced compression ratio to lower the combustion temperature and pressure level in the valve train.

Valve train systems and their components

Valves, valve seat inserts, and valve guides

MAHLE manufactures intake and exhaust valves in forged and hot-extruded versions in a multitude of materials for gasoline and diesel engines of every size. Depending on stress levels, the valves can be reinforced around the seat, hardened, nitrided, or chrome-plated. The engineers especially focus on the corrosion and high-temperature fatigue behavior of the valves. After all, exhaust valves in commercial vehicle engines must withstand more than one billion opening and closing operations at temperatures of up to 800°C.

Additional components in this assembly include the valve stem seal, the valve spring, and the top and bottom valve spring retainer.

Cam followers

The term “cam follower” is a generic term for the various elements that are moved directly by the cam lobe. They follow the cam lift and transmit the motion to the downstream valve components. Cam followers include tappets, buckets, and levers in a wide range of designs.

Camshafts

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.