Design and Application of Composite Piston for High Power Diesel Engine

The objective of the development of composite pistons is to meet an explosive increase in a worldwide energy demand and to cut down overall product cost. This paper present the design features and the field testing results of the composite piston that requires high durability and wear resistance due to high power output over P_max of 210-220 bar.

The forged steel crown and the nodular cast iron skirt were optimized using the advanced CAE technique. The parametric study of shaking-cooled oil gallery and passage was done in order to assure the optimum ring performance and prevent hot corrosion. The cooling performance was verified through visual inspection and the temperature measurement. Reliability for fastening influences the maintenance cost, and so we were trying to get rid of probability of bolt loosening using statistical techniques like hypothesis testing, etc. Surface profile of the skirt with a good wear resistance was defined by a mathematical relationship and was adjusted by a prototype testing. Finally, the results of on-going field testing will be summarized briefly.