Least life analysis of diesel locomotive crankshaft

Abstract

An analysis of the diesel locomotive crankshaft failure is presented in this paper. The crankshaft of diesel locomotives is badly affected by the peak firing pressure and cooling water temperature. The main aim of this study work was to investigate the finite element analysis on a forged steel crankshaft of diesel locomotive using ANSYS software and to suggest some novel simulation strategy that is based on the size and design consideration of the crankshaft fillet radius. The investigation included the following testing techniques and experimental process: selection of the crankshaft for investigation, visual examination, non-destructive testing of the crankshaft, failure analysis, 3D modeling of the crankshaft and finite element analysis. In this paper, a novel approach was developed in which the main crankshaft under static structural condition was analyzed by varying its fillet radius. The crankshaft was impersonated into CAM software SOLIDWORKS and after 3D modeling, its finite element analysis was performed in ANSYS software. The crankshaft was subjected to peak firing pressure and its least fatigue life was analyzed by varying the fillet radius of the crankshaft in the step of 0.5″. The analysis result shows the significant improvement in the least life cycles of the locomotive crankshaft and it was found to be 1205.9 cycles with 5/8″ fillet radius as compared to 571.54 cycles with original fillet radius size of 3/8″. The total heat flow producing thermal and surface cracks on the crankpin and main journal bearing was found to be low in the crankshaft resulting in a substantial improvement in the overall age of the locomotive crankshaft.