Robust Design of a Large Industrial Natural Gas Engine Piston

Dresser Waukesha has developed a more robust piston capable of operating under abuse conditions beyond those typically seen for large industrial natural gas engines. The results of the modeling and experimental work used to develop and validate the new robust piston will be presented in this paper. Simulation tools were first used to gain a comprehensive understanding of the causes of piston scuffing when operated under abuse conditions. With this understanding, an improved design was developed and the design changes were compared to the original piston. The performance of the new design was then simulated and compared to the original design. To investigate the robustness of the new design, the effect of reducing the major diameter clearance beyond the print specification was studied. Wear loads were predicted to be insensitive to size variations and were predicted to be acceptable even to the limit of a cold piston/liner interference fit. The predicted robustness of the new design was confirmed with experimental testing.