Innovative 3D-geometry design reduces WOB for same depth of cut.
An operator in the Williston Basin needed to drill a lower 8 3/4-in section as fast as possible through hard limestone interbedded with anhydrites and sand. Concerns centered on selecting the right bit to achieve high ROP while maintaining durability for the entire interval.
The AxeBlade ridged diamond element bit is an innovative leap in PDC bit performance, and from its success, Smith Bits engineers continue developing effective new element geometries using the ridged shape. The Axe SR scribe-ridged element is one of the results, and it combines the classic ridge with a scribe shape. Schlumberger recommended a customized 8 3/4-in AxeBlade bit with Axe SR elements strategically placed in the cone to enable higher ROP than conventional PDC bits used for offset runs. An AxeBlade bit with scribe-ridged elements requires lower WOB to maximize cutting efficiency by up to 34% over conventional PDC cutters and 18% compared to the original ridged element.
The Axe SR element enabled the AxeBlade bit to gain a higher depth of cut with the same drilling parameters used for a baseline bit with conventional PDC cutters. Using the point-loading shape of the scribe-ridged element in the cone, the ROP increased to 99 ft/h.