Taguchi Optimization and Experimental Investigation of the Penetration Rate of Compact Polycrystalline Diamond Drilling Bits in Calcareous Rocks

Abstract

In the field of drilling there is increasing interest in topics such as degradation of drilling tools and estimation of penetration speed, as well as efforts to optimize geometrical parameters and drilling processes. The current study was based on an original experimental setup that estimates the actual operating conditions of drilling tools and proposed mathematical models with and without interactions. These models characterize the penetration speed of a widely used compact polycrystalline diamond (PDC) oil-drilling bit. The special focus of this study was on the cutter penetration bit, with the aim of investigating the influence of four operating variables weight on bit (WOB), bit rotational speed (RPM), cutting angle b, and compressive strength Cs on yield maximum penetration rate, using Taguchi’s design-of-experiment concepts. In the study, 27 experimental runs based on Taguchi’s L27 orthogonal array were performed with signal to-noise (S/N) ratio, analysis of variance (ANOVA), and regression analysis being used, with penetration rate as response variables. From the optimization and experimental analyses conducted, it was observed that WOB3 (160 kgf), RPM3 (152 rpm), b3 (45°), and Cs1 (640 kgf/cm2) had significant influence on penetration rate. The optimal values obtained during the study optimization using the Taguchi approach were validated by confirmation experiments.

Keywords

• ANOVA analysis
• Drilling bit
• Penetration rate
• Signal-to-noise
• Taguchi