Case Hardening of Drilling Bit Using Taguchi Method

Abstract

Rapid wear of drilling bits in oil exploration companies occur due to friction with the sand in mud layers, this wear causes the drilling bits to consume in large quantities and leads to frequent breakdowns of drilling processes. Exploration companies are continuously suffering of these annual losses. This investigation was conducted to improve the mechanical properties of the drilling bit, it subjected to packed carburization treatment. The experimental studies were conducted under various quenching media, carburizing and tempering temperatures. The settings of carburization parameters were determined by using the Taguchi experimental design method to minimize the number of experiments. The level of importance of the carburization parameters on hardness is determined by using analysis of variance (ANOVA). The optimum combination of carburization parameter was obtained by using the analysis of signal-to-noise (S/N) ratio. The confirmation tests indicated that it is possible to increase hardness significantly by using carburization process. Based on the carburization result from Taguchi method the optimum surface hardness value calculated is 44.17HR.