Design and development of epoxy Granite base for dynamic performance Enhancement of machining center

Abstract

Machine tool sector plays an important role in the manufacturing of a variety of products. The major expectations from modern machine tools are high productivity, high precision and reliability. High static stiffness and high damping together with light weight construction are the primary requirements for the design and development of precision machine tools. Vibration is an undesirable effect in machine tools which results in poor quality of finished components, reduction in tool life and unpleasant noise. The dynamic behaviour of machine tools can be enhanced by minimizing the intensity of the sources of vibration and by improving the damping and static stiffness of the structures. Even though vibration affects all the components of a machine tool, it is highly desirable to minimize the amplitudes of vibration in the primary structures, viz., base, column, spindle head and X-Y tables. The base, being one of the main structural parts of a Vertical Machining Centre (VMC), is taken up for the present investigation. Even though active and passive dampers could improve the system dynamics, the use of such dampers has its limitations due to design complexity and cost. Moreover, a variety of dampers is required for machining of different components in a wide range of frequency. Hence, it has prompted researchers to search alternate materials with favourable damping property for building the structural components. Cast Iron (CI) and steel are the conventional materials that are widely used in machine structures. Though the above materials exhibit good mechanical properties, hey lack in damping property which is one of the primary requirements for realizing precision components. newline