Crush & Shear™ Hybrid Bit Provides Directional Drilling Stability Through Plastic Shale While Increasing Penetration Rate
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Improve drilling efficiency applying hybrid bit technology in curve
Belarus Republic, Europe
An operator drilling in the Belarus Republic was challenged by an 8½‐in. curve interval in a formation with varying rock strengths, including plastic shale. These tough transitions can cause cutting structure damage to the drill bit and make it difficult to maintain toolface control. It was a major struggle in this area to efficiently and consistently drill curve sections in one run.
The customer’s objective was to drill the 4,921‐ft (1,500‐m) curve in just one run, while maintaining precise directional control at a higher ROP than previous offset runs.
In certain formations or applications, a hybrid drill bit is required to ensure that directional targets are achieved, while also allowing the operator to maintain drilling efficiencies. Hybrid drill bits have been successful in demanding applications, where steerability is critical and/or durability is required due to formation inconsistencies.
Crush & Shear™ hybrid bit technology is a specially engineered solution that takes advantage of rock failure mechanics and provides lateral stability. It can withstand high weight on bit (WOB), while reducing torque fluctuations, thus, improving toolface control and enabling smoother drilling. This innovative solution reimagines hybrid bit technology, by placing the Geometrix™4D shaped cutters – Chisel™ PDC elements in parallel with the rolling elements, instead of in series. By optimizing PDC element placement and positioning rolling cones in the center to crush the rock (where PDC shearing action is typically inefficient), the Crush & Shear hybrid bit achieves higher rates of penetration (ROPs) and minimizes torque fluctuations. This functionality increases drilling efficiency and extends the life of PDC elements.
Feet Per Hour ROP - New ROP Record
Feet Drilled
In this challenging application, the Crush & Shear technology was utilized to design a bit (via the DatCI™ design process) that could complete a one‐bit run through an 8½‐in. curve section. This aggressive goal was successfully achieved, along with meeting thechallenging directional control requirements given the plastic shale formation. The operator set a new ROP record for production section drilling—6,040 ft (1,841 m) at an average 77.75 ft/hr (23.7 m/hr) ROP—leading to a decision to apply the same hybrid bit technology to upcoming wells in this field.