THE INFLUENCE OF THE THERMAL REGIME ON THE GUIDEWAYS OF THE MAIN ACTUATION OF A GANTRY TYPE CNC MACHINE

CNC Gantry Type Machine Tools with great distance between slides (gantry milling machines, plasma and laser gantry cutting machines, vertical lathe machines, etc) are used extensively in the manufacturing of large and long components. Because this type of Machine Tool it is used to machine large parts at high speeds, significant heat will be produce at the cutting tool level and transmitted thru the tool holder to the ram or spindled and then to the ream case guideways. Heat it’s also generated when using a ball screw actuation for the main axis because of the friction forces at the ball screw level. Due to material expansion, the heat generated during the machining process can influence the precision of the Machine Tool. In this paper, finite element analysis (FEA) was used to analyze the influence of the temperature on the rigidity of the Machine Tool guideways. The results of the studies performed will provide the machine tool builder with important information regarding the points that need to be address in order to help in improving thermal compensation.