Hydraulically expandable reamer
Enlarge boreholes while drilling with cutter block deployment and ball-drop activation.
The State Oil Company of the Azerbaijan Republic (SOCAR) was drilling a J-profile well in the Bulla Deniz field offshore Azerbaijan. The target formation consists of lithology that historically has slowed ROP to 1 m/h [3.1 ft/h] while drilling from 4,800-m [15,748-ft] MD to TD. Another challenge included operating in a high mud weight of 2.10–2.13 g/cm3 [17.5–17.8 lbm/galUS].
SOCAR also faced a complex well plan, which involved simultaneously drilling the 14 3/4-in section while enlarging it to 17 1/2-in from 2,800-m [9,186-ft] MD to 5,000-m [16,404-ft] MD. During this long section, the operator required turning the well trajectory to a projected 320° closure azimuth, building from 11° to 25°, and dropping to 19° while turning azimuth from 300° to 340°.
SOCAR and Schlumberger worked as a team to deploy a solution that would help efficiently achieve the drilling objectives while overcoming formation, BHA, and well-plan challenges.
Schlumberger deployed a customized BHA that would achieve the challenging well profile with high directional performance. The BHA included the PowerDrive X6 RSS and Rhino XS reamer to provide the directional drilling and underreaming capabilities. To perform high-quality logging while drilling, Schlumberger also ran the arcVISION and TeleScope services to acquire and transmit resistivity data for real-time interpretation and steering.
The integrated drilling BHA successfully steered the trajectory as required by following the proposal plan with 1–2 m [3.2–6.6 ft] center to center. The PowerDrive X6 RSS operated reliably for 668 cumulative pumping hours, setting a record for the longest total operating time achieved by the system. Additionally, the TeleScope and arcVISION services ran for 380 and 413 cumulative pumping hours, respectively, demonstrating their reliability.
As a result, SOCAR successfully achieved the challenging well profile and completed the directional drilling, logging, and underreaming operations without NPT, stuck pipe, or tool failures attributed to Schlumberger technology. The drilling objectives were met in 39 days, 79 days sooner than the 118-day AFE for the section.
Challenge: Drill complex J-type well profile without incurring NPT, stuck pipe, or tool failure.
Solution: Deploy an integrated drilling BHA that included