Baker Hughes used its new 6 3/4-in. Navi-Drill Ultra Curve motor with a 4 ½-ft bit-to-bend length to drill the vertical, curve and lateral sections of three wells in the Eagle Ford basin of South Texas each in a single run. Eliminating the need to trip out of hole at the kickoff point for a new curve assembly saved the operator an average of three days of drilling time per well.
The operator wanted to see an improvement in drilling efficiency over what was being experienced in comparable wells. Previously drilled wells averaged 15 drilling days from spud to TD. In addition, the rate of penetration (ROP) in the curve section was severely impacted by additional sliding time and the need to trip out of hole to change motor assemblies.
The operator’s challenge was to drill the 8 ½-in. hole section, which consisted of vertical, curve (planned with an 8°/100 ft [30.5 m] buildup rate) and lateral sections averaging 9,200 ft (2,804 m) per well.
“The Navi-Drill Ultra Curve motor is able to maintain a constant tool face while drilling the curve, resulting in more consistent buildup rates and improved ROP while sliding,” Azar Azizov, Product Manager of Baker Hughes Drilling Motors, said. “The short bit-to-bend length of this motor allowed for increased ROP in the curve section by 48% due to a reduction in sliding time. In addition, ROP in the lateral section was increased by 15% due to higher rotational limits of the assembly.”
Navi-Drill Ultra is a trademark of Baker Hughes.