A PDC design containing updated fracturing elements and utilizing in-bit sensing to optimize parameters can deliver improved ROP and drill a challenging heterogeneous section containing massive chert in one run compared to previously used PDC. The demonstration is supported by a real field case from an unconventional gas exploratory field project in Abu Dhabi.

In this unconventional field, seven wells have been drilled using three bits on average to complete the 12 ¼″ section (tricone and PDC) where the presence of chert has resulted in additional trips due to bit life. The content of cherts are large, at approximately 2,000 ft thick, which is the reason why it was decided to think of a new customized PDC bit design and use it in well number seven. The plan is to prove that is possible to achieve one run to TD by fracturing cutter development and optimized drillers roadmap using in-bit sensing.

The new unique PDC shaped cutter, with increased point surface area and thicker diamond table, makes the overall design more impact resistant and reduces vibrations while drilling. In bit sensing data is utilized to increase the efficiency in rock interaction through optimized parameters. It will be used in the ongoing exploratory project to demonstrate its advantage in terms of cost saving and rig time reduction.

The study will compare the data with previously used bit and create a basement for the exploratory field in 12 ¼″ section. A strong hypothesis is that this bit will complete the well in this particular area and optimize drilling costs in development studies.

Where such non-homogenous formations containing massive cherts can be crossed and have detrimental impact on the bit life, the novelty is to bring to the stage an enhanced combined PDC and parameter solution, which will be able to offer a different alternative by reducing torque, having healthier wells, and optimizing drilling cost in this unconventional field where drilling CAPEX reduction are paramount.

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