Controlled Turning Process for the Production of Friction-Reduced Cylinder Liners with a Defined Free-Form Geometry

Abstract

Friction in the piston-cylinder system of combustion engines has a great influence on fuel consumption. To reduce the friction of combustion engines, free-form cylinder liners and microstructured cylinder liners have proven to be advantageous. However, the combination of both processes is not industrially realized today because of an increased manufacturing effort due to a higher number of process steps. To save resources in form of honing oil in the production, the free-form can be machined by a dry turning process instead of form honing. A combination with the microstructuring process in a single manufacturing step would furthermore reduce nonproductive time. This paper presents a piezo-actuated hybrid tool that can carry out both processes. The tool wear and the behavior during free-form fine machining of cylinder liners are investigated. A process control system is introduced that controls the cylinder liner geometry by adapting the process parameters during free-form turning.

Experimental Investigation of a Free-Form Honed Cylinder Liner for Heavy-Duty Engines

“…Subsequently, the liner was manufactured at the Institute of Production Engineering and Machine Tools (IFW) of Leibniz University Hannover with a novel milling process [17,20]. The aim of the study is to compare experimentally the friction forces for a reference liner, produced with a cylindrical form, and a liner produced with such a novel free-form honed liner design, which in the hot operation state is approximately cylindrical; also, the blow-by losses are determined [21][22][23][24]. In the following, at first the experimental setup is described with the test bench of the Floating-Liner single-cylinder engine.…”