Influence of Burnishing Axial Interference on Hole Surface Quality in Deep Hole Drilling of Inconel 718

The critical components in the oilfield and aerospace industries are made of Inconel 718 alloy. Thus far, the precision of high aspect hole making operation in these has been the bottleneck. This article explores the usability of single lip deep hole drilling tools for such high aspect drilling applications. The unique construction of this tool, with integrated cutting and burnishing elements aids in producing straight and true holes. However, the process is incapacitated by the high hot hardness and abrasive nature of 718 alloy, which leads to poor surface quality. Thus, the limitations in the current process indicate the breakdown in bearing pad functionality. This study is an attempt to explore the influence of bearing pad on hole wall deformation and drill head tilting and tipping, giving rise to axial interference. It was also observed that the resultant hole surface quality is dependent on axial interference.