Wheel-tooling gap measurement system for Conform™ extrusion machinery based on a capacitive sensor

Conform™ extrusion is a very versatile manufacturing process enabling the production of a wide range of extruded profiles. It is critical to maintain a precise predefined wheel-tooling gap for the efficient running of the Conform extrusion process and to maintain high product quality. However, this is a challenging task due to the hostile environment, high operating temperatures, and required accuracy. An accurate high-temperature gap measurement system for Conform extrusion machinery, using a capacitive sensing system, is developed in this study. The sensor is implemented in a copper Conform extrusion machine, and experimental results are presented, providing for the first time a detailed view of Conform Extrusion gap behavior during production. It is shown that the proposed gap-sensing and control system results in a number of advantages, including reduced machine setup times, reduced flash (waste) rates, and on-line monitoring and control of gap size. The research is carried out in collaboration with Holton Machinery Ltd., a leading manufacturer of Conform Extrusion machinery.