An Analysis of Secondary Component Placement Using Shaped Polycrystalline Diamond Compact Cutters in Conjunction with a Fixed-Cutter Drill Bit Design

Abstract This paper examines the impact of using shaped polycrystalline diamond compact (PDC) cutters on the secondary element that tracks behind them on the same blade in a fixed-cutter (FC) drill bit. By conducting meticulous analysis and employing sophisticated modeling techniques, it is possible to strategically position the component to guarantee performance with minimal adverse effects on performance and stability. The analyses were undertaken using geometrical modeling of FC drill bits with a designated cutter configuration and secondary element positioned behind them. A representative field data analysis was conducted to ascertain an appropriate target depth-of-cut (DOC) value for the bottom-hole pattern simulation. The geometric model calculates the engagement area of the secondary elements and the impact of the shaped cutter configuration. This is combined with a drilling mechanic simulation to observe the effect on the behavior of the cutting structure. The simulation result was then compared to the field for correlation, and the analysis result was used as an input to optimize the secondary element placement for further validation in field trials. Shaped PDC cutter configurations are often used to replace legacy round cutters on an existing drill bit cutting structure to optimize the drilling performance of the bit. This alteration is frequently implemented without careful consideration of the existing secondary elements, which may prevent the realization of the full benefits of the shaped cutters. Interactions between primary and secondary cutting structures influence the secondary element engagement setup, resulting in varying drill bit performance behaviors. The modeling results indicate that PDC-shaped cutters expose the secondary element more at the same DOC than round PDC cutters. Additional comparative simulation agrees that secondary element engagement occurs earlier, which may adversely influence the performance of the drill bit. The research findings demonstrate that the precise placement of secondary elements is critical when configuring fixed-cutter drill bits with PDC-shaped cutters. Optimizing the secondary placement on a drill bit with PDC-shaped cutters enhanced the performance of the bit by achieving the desired engagement area at the target DOC for the intended application. Successful deployment of shaped PDC cutting structures nowadays requires understanding and optimizing the secondary elements placed behind them. This paper investigates one approach to evaluating and proposing optimal placement to enhance the cutting structure efficiency. This drill bit design optimization has the potential to enhance drilling efficiency and reduce drilling cost per foot, as well as reduce overall downhole vibrations, which can lead to reliability issues within the drill bit and bottomhole assembly.