The operator needed to improve drilling efficiency and bit life in a geothermal well’s 17.5-in section, which traversed high-unconfined compressive strength (UCS) igneous and metamorphic rocks. Previous attempts using various PDC and roller cone bits from multiple suppliers resulted in slow progress, frequent bit changes, and unsatisfactory ROP due to severe shock, vibration, and cutter damage in the abrasive, fractured formations.
Despite ongoing efforts to enhance bit durability and performance, the operator continued to experience low ROP and extended drilling times, with single intervals often requiring several days to complete. The challenge was to find a solution that could withstand the harsh downhole environment and deliver an improvement in drilling performance.
The operator selected the 17.5-in StingBlade bit, featuring integrated Stinger elements, to address the limitations of conventional bit designs. The unique conical geometry of the Stinger element provided ultrahigh point loading, enabling rapid brittle-fracture initiation in hard rock and improving cutting efficiency. This design also enhanced impact tolerance, reduced vibration, and maintained cutter integrity under severe thermal-mechanical loads.
As a result, the StingBlade bit drilled the entire challenging section to TD in a single run, achieving the highest ROP in the field at 22.4 m/h. This represented a 139% increase in ROP compared to the closest offset well drilled with a competitor’s bit. The improved performance enabled the operator to potentially save 55 hours of drilling time, demonstrating the value of the StingBlade bit in hard-rock geothermal applications.
