Improved Dynamic Characteristics for Machine Tools Structure Using Filler Materials

Simplified filler approach has been developed to enhance structural stability of existing cast iron columns and beds. The motivation for this research was to develop a machine tool structural material having characteristics such as, improved dynamic stability, ease in production, cost-effectiveness, and sustainability. A methodology has been developed to predict dynamic behaviour of prototype column structure using simplified reduced odd-scale model. A combination of formulae based similitude model, FE based structural analysis and statistics based Taguchi design analysis has been used to achieve enhanced structural dynamic performance of a VMC column. Similitude principles have been developed to correlate simplified odd-scale column model with existing complex prototype column through FE based 1: 5 scaled column structure. Prototype column has been replaced by simplified odd-scale column for filler optimization experiments using Taguchi design and scaling factors. Simplified odd-scale column models were filled with a number of combinational designs of unique composite filler material. VMC column structural stability in terms of excitation decay time, dynamic stress and displacement has been analyzed for present hollow cast iron structures as well as filled structures. Present methodology combination reduces efforts to develop dynamically improved machine tool structures through simplified odd-scale models, avoiding complexity involved in implementation of traditional scaling approach. As a result, dynamic characteristics have been improved by 20-30 times with introduction of composite filler material as compared to unfilled structures. This composite filler technology has been applied for patent. (C) 2017 The Authors. Published by Elsevier B.V.