In the existing production process, the problem of chatter marks occurs on the machined surface of aluminum castings, which represents incompatibilitiy with the design of the product. The chatter marks appears due to vibration during the machining process, which increases the wear of the tool, since the tools used are not resistant to vibrations.
The purpose of the work was to analyze the existing state of the production process using the SPC method, and then use the DOE method to determine the most optimal machining parameters for which the vibrations are the smallest. Sampling for the SPC analysis was direct from the existing production process. The results obtained on the basis of a regular measurement protocol were used for analysis. With this method, the process was recognized as stable, however, chatter marks were still present. With the help of the DOE method, using relatively small number of experiments we found the most appropriate parameters for eliminating vibrations. Three parameters were considered, namely, the number of revolutions of the machining tool, the feed rate and the clamping pressure, which regulates the clamping force of the workpiece to the clamping device. It was found that the pressure is the most influential and the feed rate has no influence on the quality of the treated surface.
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