OPTIMIZATION OF PARAMETERS AFFECTING SURFACE ROUGHNESS AND HOLE DIAMETER IN BORING PROCESS

Abstract

Boring operation is performed on bucket Oriels of earth moving equipment. As in other machining operations, boring process is also influenced by multiple parameters like feed rate, depth of cut, type tool & coolant, speed of cutter, etc. The objective of the present work is to improve the quality of the surface finish (Ra) and the accuracy of bore diameter. The parameters considered for optimization of the boring process are speed and feed rate of the cutting tool, while the depth of cut maintained at a constant value of 1 mm. After the completion of the boring process, each individual Oriel is checked for surface roughness (Ra) and dimensional conformance. Experiments are carried out on 18 different samples (using full factorial). The response data in the form surface finish and diameter of the bore are obtained for each sample. The Analysis of Variance (ANOVA) is carried out to find the significant factors and their individual contribution on the response functions. The most optimal values for the given boring conditions of speed (1000 rpm), feed rate (100 mm/min) and depth of cut 1 mm expected to give a hole Dia 70.005 mm and surface roughness Ra 1.843 μm. The optimal values are further confirmed by carrying out nine confirmatory tests by three different operators. The results for all the three cases are closely following the optimal solution obtained by DOE process, indicating that the solution adopted is good for the given environment of boring operation.