S3L2 Diesel Used Engine Blocks For Excavator E303 Water Cooling

Specification

Description

Cylinder Block Bolting concept

The connection between block and head can be done either conventionally or by the through-bolt technique. In case of conventional bolting, the cylinder head and grey iron bearings are bolted directly to the block resulting in high stresses in the vicinity of the thread and the bolt head. This bolting concept reaches its limits in case of high loaded direct injection diesel engines.

In order to prevent high tensile stresses in the engine block, the main bearings and the cylinder head can be connected directly by long bolts which penetrate the whole block and head, thus setting them under compressive stress only (through-bolt concept). The drawback of this solution is a more complicated assembly because bearing caps and cylinder head are not any more independent of each other, i.e. the final assembly of bearings and heads has to be carried out at the same time. This problem can be solved by screwing in the through-bolts so that head and bearing caps can be mounted separately while maintaining the load-bearing benefit of the through-bolt.

Open deck concepts

The interface between block and head, the joint face, must reliably seal the combustion chamber. But it also has to provide space for oil and water channels while maintaining at the same time sufficient stiffness against the combustion pressure and the forces coming from the head-block assembly. There are two basic design solutions: the open deck and the closed deck concept. The differentiation between these cylinder block concepts is most important as it determines the applicable casting process.

Open deck:

In the open deck concept, the water jacket is completely open towards the joint face. This design has the disadvantage of relatively low stiffness, but on the other hand, it is the only way to realize the water jacket in the high-pressure-die-casting process with a permanent and retractable steel-core. The weaker structure may lead to higher bore distortions and it must be compensated by increased wall thicknesses or an appropriate cylinder liner concept.

For engines with a high specific power density, the open deck concept can only be applied with difficulties or its application is impossible.