Development of twin wheel creep-feed grinding machine using continuous dressing for machining of aircraft rotary wing

Abstract

The purpose of this study is to develop a twin wheel creep-feed grinding machine using continuous dressing to machine precise axisymmetric turbine blades that have been difficult to machine using a conventional creep-feed machine. In order to develop such a machine, 3D-modeling and machine simulations were performed and a twin wheel creep-feed grinding machine was manufactured. Furthermore, the axisymmetric precision of the machined workpieces through practical machining was evaluated and the quality of the continuous dressing effect of the developed machine was established. In addition, experimental considerations for a proper dresser-to-wheel speed ratio and proper feed rate of the dresser were carried out. As a result, a twin wheel creep-feed grinding machine with continuous dressing is developed through machine simulation, manufacturing and performance evaluation. Optimum condition for the dresser feed rate is 0.3 μm/rev. In cases of large dressor-to-wheel speed ratio, grinding efficiency can be enhanced, but the surface roughness shows a conflicting trend. Developed twin wheel creep-feed grinding machine has satisfactory appraisal with regard to surface roughness, flatness, and parallelism. Satisfactory surface roughness below 0.1 μm can be obtained for the blade of aircraft. However, in order to perform precise machining, it is necessary to improve the structure of the twin wheel creep-feed grinding machine.

Keywords

creep-feed grinding / twin wheel / surface roughness / grinding force / continuous dressing / flatness / parallelism