Process Evaluation of Semi-Finished Products in Tyre Building and Their Impact on the Final Product

This thesis, conducted under supervision of the R\&D department of Pirelli at the Settimo Torinese industrial plant, aims to determine the impact of specific process conditions on tyre static, dynamic behaviour and overall quality. Focusing on three major semi-finished components of the tyre; the zero-degree belt, the metallic belts or plies, and the tread; each component has a unique manufacturing method. The zero-degree belt undergoes a variability study based on an anomaly, while the metallic belt and tread are subject to a global study, with a dashboard created for quality visualization. This thesis explores the effects of various production and application conditions of zero-degree belts on tyre performance. The primary factors examined include the application diameter, the tension applied, and the belts' tensile properties. The objective is to comprehend how these variables influence the end product, with the aim of enhancing performance and quality control in tyre production. Subsequently, the focus shifts to the metallic belt cutting process, analyzing process data to identify optimization strategies and methods. The tread process data, which is a 'quadruplex' extrusion aggregate, undergoes a time series adjustment, allowing for an understanding of shrinkage and other process-related variability. The study employed a range of data sources, beginning with raw material test data, followed by process data, semi-finished product test data, and finally finished product test data. The traceability systems in place at the factory were crucial for linking the data to draw conclusions. Data processing was conducted using tools from Python libraries such as NumPy, Pandas, and Keras. Furthermore, visualization tools like Plotly were utilized to develop interactive dashboards for quality visualization. The study also integrated Six Sigma methodologies to guarantee process improvement and quality control.