Optimization of the incoming inspection of camshafts using simulation modeling

According to research, up to 35% of camshafts are rejected as unrepairable, of which 50% are due to wear of cams (2/3) and bearing journals (1/3). The remaining defects are distributed relatively evenly. These statistics are collected based on the processing of a large data set and may not correspond to a particular enterprise, so it is not possible to make a universal model. Notations can graphically represent the process and provide its simulation modelling to identify vulnerabilities. A typical example of notations of BPMN. In order to increase the productivity of the camshaft fault inspection, the authors have made two models in the BPMN notation: uniform distribution of probability of defect detection by operations and non-uniform distribution of probability, according to statistics. Simulation modelling of the fault inspection of 100 camshafts of the YaMZ-236 engine built in the BPMN notation was carried out in the Business Studio software. In the real process, the parameters of 100 shafts were controlled in the conditions of the specialized repair enterprise AB-Engineering by universal and specialized measuring instruments. After comparing the real process and its model, closer results were obtained with non-uniform distribution, which was taken into account during the optimization. The input inspection procedure was optimized based on the percentage of rejected products and the operation duration. The time spent on fault inspection after optimization was reduced in 1.35 times, the discrepancy between the model and the real process data did not exceed 5%, which indicates a correct approach to modelling processes associated with a high degree of uncertainty.