Modelling and Evaluating the Heat Transfer of Molten Thermoplastic Fabrics in Automated Handling Processes

Abstract

Modern manufacturing processes for lightweight parts and products have to face new challenges regarding the changed material properties. For instance, one of the upcoming new lightweight materials, which focusses on a large scale production, is the so called organo-sheet. An Organo-sheet is a continuous fiber reinforced thermoplastic which has to be processed above melting temperature. At this temperature, the organo-sheet loses its stiffness and changes into a limp state. In this state, it is possible to form the flat organo-sheet into three dimensional shapes. However, the heat transfer to the environment, such as the air, the forming-tool or the robot gripper, causes a fast cooling. To identify the thermal properties, this paper focuses on the analysis and characterisation of common robot grippers for handling heated organo-sheets in fully automated manufacturing processes. The paper presents the results of handling experiments using conventional suction-, needle- and clampgripper as well as a heated needlegripper. In addition, a heat transfer modelling approach is introduced.