Glass forming process characterization for low delamination propensity vials production

This thesis work presents the results of a six month internship carried out the Nuova Ompi division of Stevanato Group, a company specialized in the production of drug containment systems such as vials, syringes and cartridges. The project in which the work carried out in this thesis takes part has the objective of studying the glass vials forming process and its variables in order to avoid the undesired phenomenon of glass delamination. To this aim, the thesis involved two parallel analyses. The first one was devoted to the assessment of process setting transferability between different glass forming machines, in order to produce a given set of dimensional and chemical characteristics to the final vial. In this sense, the results have shown that gas flow and burner flame temperature represent two of the most important process parameters to tailor the vial features. On the other hand, the experiments carried out have led to the conclusion that the flows or temperature alone are not sufficient to univocally define the repeatability of the process. Ascertained that, the project focused on other theoretical critical parameters. A process mapping for the identification of the most critical process parameters was carried out, with a subsequent analysis of a subset of them to understand the relationship with the quality requirements of the final product. Tests were carried out on the parameters of the fume removal system installed on machine and on the type of burner configuration to obtain a good chemical resistance and dimensional conformity of the vial. These experimental campaigns of tests laid the foundation for setting up a Design of Experiment (DoE) that will be performed in the subsequent phases of the project only after making some improvements on process control instrumentation and on process repeatability and stability over time.