Measurement of cutting forces and optimization of machining parameters in cylindrical grinding

Abstract

Grinding is one of the most important manufacturing process for high precision parts. Grinding force has a direct influence on grinding wheel wear, grinding temperature, the surface quality of the workpiece and the design of machine tool component. Also, the cutting force is proportional to the specific energy in grinding and this influences the performance and surface integrity of the workpiece. Hence the measurement of forces in grinding process is very important. In surface grinding, forces are measured using the dynamometer placed on the grinding table. But in cylindrical grinding the force measurement is a difficult process compared to other machining and surface grinding process, since the workpiece and the wheel are in motion. Also, the available force measurement methods are more suitable for research laboratory than for industrial application. In all these methods the modifications are done either in the workpiece or in the machine setup. Therefore, in this research work, a strain gauge based force measurement setup has been developed and it can be implemented in the industrial work without any major difficulty The detailed investigation was conducted in ANSYS to analyze and identify the region of strain in the stationery tailstock in cylindrical grinding due to grinding forces. It is observed from the ANSYS results that the elastic deformation is more in the area of conical portion of the dead center and it increases with an increase in the load. Using this result, the location to place the strain gauge is identified and two wheatstone bridge circuits are constructed to measure the signals of the tangent and the normal component of grinding forces. The normal and tangential component of grinding forces are measured using the experimental setup. A hall effect sensor based current probe was used for measuring the grinding power of the spindle motor. The tangential component of grinding force is also derived from the measured grinding power.