Adaptronic form honing - manufacturing methods for compensating cylinder bore distortions: Presentation held at WGP Jahreskongress 2012, Berlin, 27. - 28. June 2012

Abstract

Cylinder bore finishing requirements are defined by quality features such as roundness and cylindricity as well as by the manifestation of the surface profile. Honing is a proven manufacturing method s to achieve this. Undesirable distortions of the cylinder shape occur under operating conditions in a reciprocating internal combustion engine. These negatively affect the tribological system of piston, piston ring, and cylinder bore. As a result, efficiency deteriorates and oil consumption rises. The cylinder crank cases are finished in a defined tensioned state to compensate for distortions. This results in a highly complex manufacturing process and is only suited for compensating static distortions. Further increasing machining requirements resulting from strategies such as lightweight construction, downsizing, and friction reduction are pushing conventional honing methods to their technological limits. Adaptronic form honing constitutes a production engineering approach to manufacturing a free form in the cylinder bore. The objective is to keep inverse distortion geometries in store as macro shapes. These will then represent ideal cylinder shapes under the influence of distortion mechanisms in a defined engine operating range. Tool and process development and the analysis of machining results with respect to productivity, shape accuracy, and surface topography are presented and viewed as potential options for optimizing the tribological system of piston, piston ring, and cylinder bore. Other options such as shortening the process chain will be derived