V2403T C2.4 Diesel Used Engine Blocks For Excavator E307 Water Cooling

V2403 C2.4 Diesel Used Engine Blocks For Excavator E307 Water Cooling

Specification

Description

Cylinder Block Design

Alloys commonly used for engine block include the alloys EN AC-46200 (AlSi8Cu3) and EN AC45000 (AlSi6Cu4) which are similar to the American standard alloys A380.2 and A319, respectively. These hypoeutectic Al-Si alloys are generally produced from recycled aluminium and are mostly applied for engine blocks produced with gravity casting processes.

The relatively high Cu content enables them to retain their strength at elevated temperatures and makes them easily machinable. The as-cast (F) condition and the T4 and T5 heat treatments are commonly used.

Almost all high pressure die cast engine blocks are produced with the very common secondary alloy EN AC-46000 (AlSi9Cu3(Fe)). Except for a moderate annealing for the reduction of residual stresses, no further heat treatment can be applied in general.

Engine blocks cast from the alloys EN AC-42100 (AlSi7Mg0.3) and EN AC-42000 (AlSi7Mg) achieve very high strength and elongation values at room temperature when a T6 heat treatment is applied. Attention has to be paid to residual stresses resulting from quenching during T6 treatment. The higher resistance to cracking in the plastic regime offered by these alloys enables them to survive the much harsher thermal fatigue loading conditions encountered in this application.

There is some sacrifice in machinability (mainly burring) and added cost in heat treatment since a T6 or T7 temper is usually required. Due to limited contents of impurity elements such as Fe, Mn, Cu, and Ni, there is also an additional cost compared to the secondary alloys mentioned above.

Blocks from hypereutectic AlSi alloys (AlSi17Cu4Mg) are usually produced with low pressure die casting and are subsequently T6 treated. Also this alloy is generally more expensive compared to the standard secondary foundry alloys.

Applicable casting processes
For the production of engine blocks, a multitude of casting technologies are applied. From an economic aspect, for mass produced engines, highly automated casting methods using sand moulds (“core package processes”), where the cycle time is not limited by the solidification conditions, are competing with die casting methods where the cycle time is limited.