When operating in the Chinarevskoe field, Zhaikmunai LLP has traditionally used conventional-motor BHAs. Initially, A962M motors were used to drill the 11⅝-in sections at an ROP of 14 m/h. However, due to the inability to fish the A962M motors, they were replaced with A825M motors, which lowered average ROP to 10 m/h. Drilling parameters were altered to maintain verticality with packed BHAs, which lowered ROP and increased overall well construction time.
SLB drilled the entire section in a single run using the PowerV™ vertical drilling RSS PDC cutter, which drilled shoe-to-shoe in one run, increasing ROP by 57%, and saved 5 days off planned 10-day drill time, saving USD 210,000 per well.
SLB worked to develop an integrated drilling solution for Zhaikmunai that included PowerV RSS and a customized PDC bit.
When drilling, the PowerV RSS actively steers downward, regardless of the azimuth of any inclination present. Using a closed loop inclination mode, the vertical RSS senses if the hole inclination is building and automatically determines the direction required to steer back to vertical. Once vertical, any deviation tendency is corrected automatically downhole, thereby maintaining without any operator interaction from surface.
The first well drilled with the PowerV RSS achieved ROP of 22 m/h, the fastest hole section drilled in the field. This represents a 57% increase in ROP compared with conventional motor assemblies, which achieve an average ROP of 14 m/h. Because of these results, Zhaikmunai replaced its conventional BHA design with the PowerV RSS for the 11⅝-in sections of the entire project.
