This paper reviews how the Rotary Steerable System (RSS) market has changed over the last two decades. It explores current market forces; specifically the shift in RSS philosophy resulting from ever-improving motor steerable technology. It describes how the need for longer laterals with minimal tortuosity, maximum drilling efficiency, reduced risk of unplanned events, and elimination of AFE overspend, along with the paradigm shift in the directional drilling market seen since 2014, drove the specification for a new-generation RSS tool. The paper describes the development of a new RSS with a topology and control concept that allows full proportional control of bias from a fully rotating, push-the-bit tool, with the ability to "turn off" any bias during operations where side force is undesirable and to minimize potential tortuosity. It describes how the design team focused on modular design and rapid turn around of tools, in order to maximize utilization and efficiency. Field-test results are included, which demonstrate build and turn at up to 10°/100 ft. and the ability to drill accurate lateral sections. Field results also include the use of ultrasonic imaging while drilling to investigate hole quality.

In the current market climate, the industry is in a time squeeze and it is crucial for future value generation to reduce the well construction time and cost. Drilling Optimization practices have helped to increase drilling efficiency while reducing the likelihood of downhole failures. To see this effort further, an adequate engineering plan to design the operation strategy, along with the understanding of the geological challenges, assists in establishing a more robust real-time optimization program. Real-time drilling optimization helps to improve drilling performance by providing early warning detection of downhole drilling events, maximum allowable deviation of planned vs. actual hydraulics and torque & drag measurements, and finding the "sweet spot" by use of drilling parameters. These processes can then further be optimized by the integration of pre-job engineering and formation evaluation measurements. Pre-job engineering seeks to ensure the BHA is able to resist vibration- related events, while the drillstring and bit are selectively examined for optimal hydraulics and resistance to torque and drag related issues. The pre-job engineering also considers ways to improve the rig’s overall efficiency, by eliminating invisible lost time while both in and out of hole. New generation of logging while drilling measurements help to provide reliable prediction of pore pressure for early warning of circulation problems, collapse events, lost circulation, blowout, and kicks. This process involves a depth-by-depth correlation between actual borehole lithology and pre-modeled unconfined / confined compressive strength (UCS/CCS). Optimized mechanical specific energy is evaluated using drilling parameters such as torque, RPM and ROP. The resulting two curves are then defined by calculating the value of MSE/CCS-UCS fraction to derive a drilling efficiency indicator. By correlating these curves, the drilling optimization team can identify geological formations that have the optimum correlation then compute the efficiency indicator for the interval, using it as baseline for drilling each hole section. This workflow guides the operations to make necessary real time adjustments to mitigate potential problems. The workflow demonstrates the integration from the pre-job engineering design to the automation of the real time integrated evaluation, along with the accuracy of the new generation of Logging While Drilling technologies as a cost-effective solution to mitigate non-productive time and optimize drilling rates through the implementation of a solid drilling optimization program during the execution of ERD, offshore and unconventional projects.

The geological complexities of shale formations dominated by lamination deposition mechanisms make formation evaluation a challenge for hydraulic fracture operations. Logging While Drilling technologies have evolved to provide valuable information for a reliable approach in anisotropic shales. One of the most frequent considerations is well productivity and how the new technologies and evaluation methods can help to mitigate the uncertainty of the completion and improve fracturing performance. The incorporation of the TIV anisotropy evaluation from LWD azimuthal acoustic measurements can help characterize the impact of the laminations stage by stage or even a more detailed cluster by cluster analysis. Information from the LWD azimuthal sonic tool can help provide a better understanding in regards to the rock mechanical behavior in horizontal shale wells, as well as the brittleness interpretation providing a more realistic approach to the lamination structure of the shale deposition. Quantifying TIV anisotropy is a very important key evaluation factor to optimize the completion program likewise the well productivity. In conjunction with the LWD azimuthal sonic information, the LWD spectral gamma ray measures isotope concentrations (such as Uranium, Potassium, and Thorium) can be confidently integrated into the unconventional petrophysical interpretation calculations of Total Organic Content. This analysis is incorporated with the geomechanical and anisotropy evaluation to select the best fracture placement and design in an unconventional environment. The anisotropic brittleness analysis identifies the zones where the best fracture propagation will be achieved while the petrophysical analysis indicates how productive these fractures should be. Through the geometric fracture simulation the best set of recommendations for the fracturing operation are developed to predict the conductivity area which contributes to the well productivity. This paper will show the impact of the TIV anisotropy into the geomechanical evaluation, beginning with the unique real-time fracture placement methodology leading to an optimization of the anisotropy analysis to generate the best frac design to avoid expensive completion programs and reduce uncertainty on fracture placement evaluation.

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