In North Dakota, a major operator was dealing with a well design that required a bit able to provide high penetration rates through highly variable rock, as well as directional capabilities to build and hold long tangent sections. This challenge was compounded by numerous major formation groups with variable rock strength and composition. The formation variability greatly affected the stability and efficiency of the bit and bottomhole assembly because the instantaneous depth of cut is constantly changing.
The operator used the DualHelix multiformation performance bit to increase performance in a long vertical interval. This choice resulted in improved penetration rates and reduced average drilling hours, saving time and costs for the operator. This innovative drillbit uses the geometry of cutter placement to change how cutters engage according to the depth of cut. By using variable curvature of cutter positions along the bottomhole pattern, the wake of the leading cutters can be used to optimize cutting efficiency. This passive engagement requires no moving parts, relying only on the variable sweep developed by the three-dimensional aspect of shearing rock removal. The resulting shape of the body and blades of the bit also provides an advantageous hydraulic layout to improve bit cleaning and cutter cooling based on cutter loading.
