Increase efficiency of drilling reentry well
In a multiyear, multiwell drilling program in Kazakhstan, Karachaganak
Petroleum Operating (KPO) wanted to restore production in a nonproducing well.
To accomplish this, KPO needed to drill a 6-in sidetrack from a whipstock
installed at a near-vertical inclination and land well at 86°, which would
require a dogleg of 6°/30 m to 9°/30 m.
In the past, KPO used conventional RSS BHAs to achieve time and
tortuosity gains. However, for dogleg assurance reasons, the build section
could only be drilled with mud motors, which required multiple bit runs. KPO
wanted to drill the 6-in reentry well more efficiently than previously had been
possible to help restore production to nonproducing wells.
Use PowerDrive Archer 475 RSS to reliably build high DLS curve
Schlumberger recommended drilling the high dogleg-severity (DLS) curve
using the PowerDrive Archer 475 high build rate RSS, a highly reliable hybrid
steering system with a dogleg capability of 18°/30 m [18°/100 ft].
Using the IDEAS integrated drillbit design platform, Schlumberger also selected
an application-specific directional PDC bit from Smith Bits for use with the
PowerDrive Archer RSS to provide greater directional response, minimal
vibration, and high ROP.
Drilled reentry well in one run at record ROP
The PowerDrive Archer 475 RSS and PDC bit was run from the whipstock
window to TD, a total of 1,362 m. The well was placed precisely at the required
TVD using a hold-inclination-and-azimuth command in the lateral section.
This BHA enabled KPO to drill the reentry well in one run at a record
ROP of 8.6 m/h for the field and achieve the planned dogleg of 6°/30 m to
9°/30 m. The sidetrack was completed 8.5 days ahead of schedule, which was
based on past experience using conventional mud motors. The time saved with the
PowerDrive Archer RSS reduced operating cost by USD 2 million, and KPO plans to
use this method to restore production in other nonproducing wells in its