Finite Element Analysis of Installation Failures in Engine Cylinder-Liners

A cylinder of an internal combustion engine subjects to excessive heat, fine abrasive contact and wear during the operation.  Therefore, usually an internal combustion or a reciprocating engine incorporates a replaceable internal liner for each cylinder in order to cope up with the wear-out caused due to friction between the piston rings and the interior of a cylinder.  The thickness of a cylinder liner depends upon the engine and the planned life time of a cylinder liner and some of the engines incorporate a thin-walled liner.  However, there exist concerns regarding the failures that occur during the installation of liners at the authorized and unauthorized service centers.  Manufacturing defects and the procedural defects of installation suspect the occurrence of failure during the installation and the cylinder liner manufacturing industry concerns about the delineation of the causes and the improvement of the reliability of products through the engineering analysis.  Analyzing the probable causes from the points of view of the design, manufacturing, and authorized and unauthorized installation procedures define the problem.  The problem involves the simulation of the process of press-fitting into the cylinder bore.  A choice of finite element analysis using commercially available software ANSYS helped in the analysis of the probable causes of failure.  Estimation of the probable loads experienced by the cylinder liners during the probable procedures existing in the installation of liners paved way to the definition of loads prevailing in the problem of relevance.  Prediction of the nature of contacts that experience in the current problem and the impact of application of the loads enabled the definition of constraints for the simulation procedures.  Reference material properties chosen in the conservative sense modeled the problem.  Choice of the two dimensional and three dimensional analyses as appropriate for the simulation of probable causes provided an economical and cost effective means of analysis.  The configuration of cylinder-liner chosen for the analysis was found fit from the points of view of the design, manufacturing and installation.  Evolution of the recommendations for manufacturing and installation of such thin liners concluded the study.  Observance of higher than critical stresses during the incorporation of manufacturing and installation abnormalities in the simulation provided foresights into avoiding nicks, blurs and improper fillets, and achieving the parallelism, stress relieving and alignment measures for the cylinder bore.  Recommendations of manufacturing and finishing processes including the detection of residual stresses and relieving, and machining process parameters found useful.