Predictive maintenance application with digitalization in welding station: investigation of structural and mechanical properties

Total predictive maintenance (TPM) is a maintenance method that takes precautions against the problems encountered in enterprises and ensures a systematic approach in every area within the enterprise. Studies in this field aim to increase performance, prevent any malfunction with predictive maintenance, prevent problems that have occurred or will occur with systematization within the enterprise and prevent financial losses in the enterprise. The latest innovations in this field are to strengthen TPM studies with digital tracking tools. This thesis study includes the process of analyzing and reducing the failures, performance losses and electrode consumption in the capacitor discharge welding station in the enterprise with the help of a digital tool created as a sub-component of the Manufacturing Execution System (MES). In the first stage of the study, the identification process of the electrodes used in the station was carried out by laser marking and the cycles of the electrodes used were also determined. Then, the digital tracking system of the identified electrodes was realized by performing the identification of the relevant electrodes in the digital component created through the MES system. In addition, the electrodes were classified according to their visual defects and the reasons for change were added to the digital system in the light of this classification. The reasons for this change are spattering, deformation, arcing and the end of the life of the electrode in the absence of defects. In addition, 20 of the parts produced with different electrodes from the parts produced with the first batch of electrodes were subjected to some tests to check whether there was a deviation in the weld quality after the design change of the electrodes. 10 specimens were subjected to compression test and the remaining 10 specimens were subjected to Scanning Electron Microscope (SEM) analysis and visual weld quality was also examined in both tests. No deviations were encountered in the test results. The correlations between the causes of electrode failure and the mechanical adjustment requirements in the station were analyzed through the digital tracking system. As a result of this analysis, it was concluded that burring and deformation, which are among the reasons for electrode replacement, occur due to deviations in the position of the produced part and since this deviation recurs within a period of 6 months, it was added to autonomous maintenance. In addition, since the reason for the arcing of the arcing electrodes was a single case due to the incomplete calibration method performed at the station, the method was updated and trainings were assigned to the relevant personnel. Finally, it was observed that end-of-life electrodes were stably replaced as long as the station met the desired conditions, and for this reason, it was a parameter monitored within the scope of predictive maintenance. All these studies were carried out within the scope of TPM pillars. As a result of the study, an improvement of 4.7% was observed across the line. In addition, a gain of 0.4% was achieved in the scrap rates in the plant, which resulted in a decrease in the number of scrapped parts. Finally, a 3% reduction in consumables was observed, reducing electrode consumption and providing a financial return to the business. This study aims to draw attention to the fact that digitalization in TPM systems is an important innovation for enterprises and to encourage enterprises to carry out different future studies in this field. The improvements obtained in concepts such as machine performance and scrap rates, which are key performance indicators in the whole enterprise, provide a reference for the development of such systems.