Improve well-construction performance, efficiency, and coordination while reducing wellbore instability.
Published: 09/27/2017
Published: 09/27/2017
With unstable, swelling shale and high concentrations of hydrogen sulfide and carbon dioxide, the Bayandyskoye field presents a challenging drilling environment to operators. LUKOIL recently reamed and cased one well in 20 days. However, with a focus on continuous improvement, the operator sought to reduce well construction time even further by implementing new technologies that could streamline operations.
To improve operational efficiency and address wellbore stability issues, Schlumberger recommended the Direct XCD drillable alloy casing bit—a PDC bit specially made for drilling and casing challenging vertical wells to TD in one run—modeled in the IDEAS integrated dynamic design and analysis platform. The bit drills on standard casing that is rotated at the surface, enabling casing-while-drilling operations.
Drilling with casing reduces annulus size and plasters cuttings into the borehole wall, producing a stronger borehole for cementing. Multilobe torque rings increase torque capacity while protecting threads from debris, eliminating the need for additional downhole equipment.
Using the Direct XCD bit, LUKOIL reamed and cased to 2,671-m [8,763-ft] TD in just 4 days—reducing well construction time by 16 days and setting a new field record. Once the bit reached TD, it served as the casing shoe, enabling LUKOIL to drill through the bit and eliminating the need for a dedicated drillout run.
Challenge: Improve well construction time and cost efficiency while drilling in an unstable shale formation.
Solution: Run the Direct XCD drillable alloy casing bit as part of a casing drilling strategy.
Results: