Drill 16-in section through highly interbedded formation

An operator was drilling a development well in the Sabriyah field of northern Kuwait. The well plan included drilling the 16-in section from 1,230-ft [375-m] MD to 6,000-ft [1,829-m] MD, a total of 4,770 ft. The section would intersect carbonates interbedded with shale as well as the anyhydritic Rus Formation and dolomitic limestone Radhuma Formation, which are hard and typically generate stick/slip. Conventional TCI bits used to drill offset wells in the formations delivered insufficient ROP. The operator’s objective was to complete the entire section at a higher ROP than was achieved in offset wells.

Use StingBlade bit and Schlumberger mud motor to complete section

Smith Bits recommended an integrated drilling solution that included a high-performance mud motor and a six-blade StingBlade bit with 16-mm cutters. The mud motor would enable the high ROP required to decrease drilling time and reach TD faster than was possible using conventional technologies. The StingBlade bit was chosen because it leverages the superior impact and wear resistance of Stinger conical diamond elements, which are strategically positioned across the StingBlade bit face. The elements feature a unique 3D geometry and thicker diamond table compared with conventional PDC cutters, enabling the StingBlade bit to deliver improved footage and ROP while minimizing shock in challenging drilling applications that can cause impact damage to conventional bits.

Engineers used the DBOS drillbit optimization system to better understand the characteristics and hardness of the formation to be drilled. To simulate the dynamic behavior of the bit and BHA design in the formation, Smith Bits used the i-DRILL integrated dynamic system analysis service. Using these softwares, the engineers were able to recommend the optimal BHA configuration and perform a detailed drilling parameter sensitivity analysis using matching field conditions and operating parameters. A drilling parameter road map was prepared to provide the operator a matrix of optimal drilling parameters to help mitigate stick/slip and other downhole vibrations.

Completed the section 3.5 days faster versus AFE

The integrated drilling solution helped the operator drill the entire 16-in section in one run. ROP in the Rus and Radhuma Formations doubled, and overall on-bottom ROP was 24% faster compared with conventional bits in offset wells. As a result, the operator saved 3.5 days of drilling time versus AFE.