W.S.G. Isaac Newton

VDL ETG Almelo is a high-tech machine manufacturer, which involves both assembly and parts production of small series. Working there during my internship was an amazing experience, in which I learned a lot. Within the Parts Manufacturing department, the department where I was located, the main focus is on machining highly complicated mechanical components. As the variety of products is high, there is a wide range of cutting tooling available and the tools are used for a variety of products. The tool life of the cutting tool depends on its application, i.e. rough milling vs. final milling, milling through welds vs. solid material. A cutting tool is used in various products, the application for each product can be different and therefore the wear per unit of time usage is different per product. Currently, the tool life is defined in a worst-case situation. The time of usage is timed per cutting tool, once the predefined tool life is exceeded, the operator will be informed.

Currently, the determination of the tool life is an iterative process, in which the operator is visually assessing the state of the cutting tool, after which the tool life is shortened or extended for the next tool. This process is functioning, though optimization is possible. Not the full tool life is used, as the worst-case tool application is assumed.

My research involved an investigation of possibilities to monitor the condition of the mills during the operation process. Once the tool starts wearing, vibrations might occur, and the required power increases. These characteristics could be indicators that can trigger the replacement of the cutting tool once a threshold is exceeded.

During the assignment, I researched wear characteristics in machining. Also, suitable sensors that monitor wear characteristics (indirectly) in operational milling machines were reviewed. A test setup for monitoring the wear characteristics and selecting a measurable wear characteristic for future monitoring was built. Last, design considerations, test results, and recommendations were documented