The operator faced significant challenges drilling a 16-in section in a Middle East offshore field characterized by highly variable lithologies, including shale, marl, chalky limestone, dolomite, competent carbonate, and evaporite-bearing intervals. The section required building inclination from vertical to 35° within a high-risk anticollision zone, while contending with rapid formation changes that caused variable loading, torque fluctuations, shock, vibration, and potential cutter damage.
Previous attempts using conventional PDC bits were hampered by circulation losses, cutting-structure damage, and inconsistent steerability, resulting in inefficient drilling and increased operational risk.
To overcome these obstacles, the operator needed a drill bit that could deliver high durability, dynamic stability, precise directional control, and consistent drilling efficiency across the entire heterogeneous formation sequence. The goal was to drill the interval in a single run, reduce drilling time, and improve overall well construction performance.
SLB deployed the 16-in Spyder hybrid drill bit, engineered to merge the strengths of fixed-cutter and two-cone technologies. The bit's hybrid architecture uses PDC cutters for efficient shearing in softer and medium-strength formations, while strategically positioned TCI roller cones engage harder and interbedded lithologies through crushing and impact-resistant cutting mechanisms. This complementary approach minimized cutter exposure to impact loading and abrasive wear, enhancing durability and maintaining consistent performance throughout the interval.
The Spyder hybrid bit delivered excellent dynamic stability by mitigating torque oscillations, stick-slip, lateral vibration, and whirl—even during abrupt formation changes. Its advanced directional characteristics enabled precise trajectory control and reliable toolface response during build sections, allowing efficient navigation through collision-sensitive areas while maintaining high drilling efficiency.
As a result, the Spyder hybrid bit drilled the entire 5,220-ft interval in a single run, achieving an average ROP of 77 ft/h and building inclination from vertical to 35° with a steerable motor. The operation eliminated the need for a conventional two-BHA approach, saving significant rig cost.
Compared to average offset wells, the Spyder hybrid bit achieved a 65% increase in ROP and reduced drilling time by 45 h. When benchmarked against the best PDC offset, it delivered 16% higher ROP, 48% lower torque, reduced shock and vibration, and superior toolface control, demonstrating the value of hybrid bit technology for challenging directional drilling applications.
