ConformTM automation with gap sensing and control

The paper presents the results of an investigation into the automation of the Conform^TM extrusion process. For the Conform^TM extrusion process to run efficiently and achieve high product quality, it is critical to maintain a wheel-tooling gap within close tolerances of a pre-defined value. An active high temperature gap sensing system is discussed that is implemented on copper Conform^TM machines. The results from gap measurement tests, using a capacitive sensing system, are presented. The operator sets a desired gap using an LVDT-based feedback PID controller with a hydraulic actuation system. The benefits of the sensing system and the need for an automatic gap control system and associated benefits are also discussed. A microcontroller based feedback system is being developed, at present, for providing automatic control to maintain a required gap, specified by the operator. By providing gap sensing and semi-automatic control, less flash (waste) is produced. This will be improved further with automatic gap control. The research is carried out in collaboration with Holton Machinery Ltd, a leading manufacturer of Conform^TM extrusion machinery.