ANALYSIS OF SURFACE ROUGHNESS IN DRILLING USING RESPONSE SURFACE METHODOLOGY

Abstract

Drilling is one of the elementary machining processes of making holes and it is used in manufacturing industry like watch manufacturing industry, Aerospace industry, Automobile industry, medical industries and semiconductors. In this study, an attempt has been made to minimize the surface roughness and torque in the drilling process on an EN-31 specimens of height (70mm), diameter (40mm) by application of the DOE (Design of Experiment) method integrated with RSM. Taking into account the drilling speed, feed rate and the drill diameter the machining controlled parameter thrust, torque and surface roughness, are optimized based on the RSM method. A Run order was developed by taking the three factors each having 3 levels using Statistical package. Based on the sequence, drilling was done by taking HSS drill bit of different size diameter. The resultant data are analyzed by RSM to find out a combination of optimal drilling conditions. In particular, it is found that high speed and low feed and small diameter is giving a better result having low surface roughness, torque and thrust.