When designing a large-sized cast product for a multi-spindled machine tool, such as a multi-turret type multi-tasking machine, we must first determine its thermal deformations by the finite element method (FEM) in order to ensure that the structure is designed with high thermal rigidity. Casting technology has progressed so much that we can now form more complicated internal structures and produce much thinner and lighter cast products. Moreover, since designing cast products has become much faster, higher-efficiency analytical techniques are also required. Such analytical techniques are operated by designers where analyses and design are executed interchangeably. In this study, we compared the experimental results to the analytical results in order to evaluate the employed analytical technique based on an actual analysis of a multi-tasking machine bed with a few different rib structures.

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