ONGC’s concerns
ONGC wanted to increase ROP, improve cost efficiency, and avoid bit damage and NPT while drilling through interbedded weathered and basaltic formations.
What they tried first
The challenging application caused premature impact damage to conventional roller cone and PDC bits in the offset well. Junk recovery runs increased NPT, and unstable bit and BHA configurations caused high shock and vibration, increasing drilling time and costs. Drilling the section to TD required nine to 15 roller cone bits at an average ROP of 0.5 to 1 m/h and an average meterage between 60 and 100 m.
What Schlumberger recommended
Combined with two stabilizers in the BHA configuration, a new design of 16-mm hybrid AxeBlade bits with Stinger elements created for the application would improve stability compared to baseline configurations used in offset wells.
