Estimation of Wear Depth as an Approach to Predict Tool Service Life in Cold Forming Process

Abstract

Wear phenomenon is considered as a predominant parameter in the forming processes causing the shorten tool life which in turn increases the production costs. In this study, wear depth of tool components for multi-stages of metal shell of spark plug (MSSP) manufacturing was analyzed using Archard's model with FE simulation software. The 3D geometry models were built using SolidWorks software then the models files were exported to Simufact forming software to do the settings of preprocess and FE analysis. The cylinder compression test and ring compression test were executed to get the flow stress and frictional factor respectively. Product parts dimensions, forging loads, effective stress, relative sliding velocity and contact pressure were solved and discussed. Subsequently to verify the analysis acceptance, the actual product parts measurements which obtained by coordinate measuring machine (CMM), were compared with the simulation results. It was found that the deviations of actual MSSP geometry dimensions less than (4%). Also verification is performed to forging loads at each stage which gives a good agreement between actual and FE simulation results. Finally, the wear depth of tool components were calculated for each stage using the FE software. Based on the results of wear depth from simulation and tolerance rages of actual product parts, tool service lives were predicted to find the productivities for each tool component. The results of FE simulation were compared with the CMM measurements for known productivities tool components from actual production line, which gives a good accuracy and acceptable agreement