Recent manufacturing and hardfacing advances have produced a steel-body PDC bit (SB-PDC) capable of efficiently drilling interbedded formations at significant depth. These technological advances have increased the bit's resistance to abrasion/erosion and enabled a new style steel-body PDC bit to drill formations in Egypt's western desert previously drilled by matrix PDC bits. Field tests have confirmed the steel-body PDC bit can outperform matrix PDCs in a wide-range of interbedded applications that contain a heterogeneous mixture of shale, sand/siltstone, and limestone. The approach combines optimized cutting structure design and premium PDC cutters that enable the steel-body PDC bit to drill the abrasive sand/siltstone component. The bit can also efficiently drill shale and soft limestone due to its hydraulic efficiency which was a factor limiting performance improvement in previous designs. The bit solution employs: ➣Cutting structure optimized using FEA-based modeling system➣Premium grade PDC cutters➣Next generation of abrasion/erosion resistant hardfacing material➣Hydraulically efficient bullet-shaped body type The new SB-PDC technology was deployed in a sequence of tests in different applications and fields in Egypt's western desert. The trials were run in different lithologies at different depths. Direct comparisons to relevant matrix PDC technology and other available steel-body bits clearly demonstrates the new-style steel-body PDC bit's value by setting new benchmarks and reducing cost/ft.

Efficiently drilling the deep lithology column with PDC bits in Egypt's Western Desert (WD) has been extremely challenging. The formations-Alam El Buwaib, Masajid, Zahra, and Safa-contain a volatile mixture of highly interbedded sandstone, siltstone, and shale that have damaged PDC bits, especially at depths of 12,500 ft and greater. In addition to the demanding drilling requirements, operators are pursuing multiple targets per well for better cost optimization. Finally, a tight control on target drilling days has required more efficient and consistent drilling solutions. In addition, the array of different drive types and BHAs used in the area have all suffered and exhibited the same symptoms: high stick/slip, high shock and vibration, failure of MLWD tools, RSS, or positive displacement motor (PDM), and premature tripping for bit changeout.To solve the issues, several 8½-in PDC bits were developed that feature a central conical diamond element (CDE). The bit designs feature an abbreviated cutting structure profile at the bit center that generates a rock column that stabilizes the bit. The rock column is constantly being destroyed with axial force as opposed to traditional shear, resulting in lower torque magnitude and fluctuations. The reduction in torque fluctuations increases the bit's potential to solve a combination of vibration issues. The new-style bits were scheduled to be field tested in different wells and runs in Egypt's Western Desert applications, including with classical rotary BHAs, with different RSS/PDM types in a variety of directional well profiles, at different depths, and in different fields. This robust field campaign was performed with the intent of proving and providing a consistent solution and grounds for a paradigm shift of how PDC bits need to be constructed.The results of the multifield campaign delivered low levels of torque and torque fluctuations; enhanced bit durability, frequently replacing two bits or more; low vibration levels; a significant increase in cuttings size, thereby enhancing surface formation identification; and high dogleg capability and smooth directional response. The bits also increased footage and overall ROP due to preserving the cutting structure, producing a performance step change and achieving consistent lower cost per foot across the WD field.The field test campaign results in Western Desert spans over 60 runs conducted over a 12-month period. A close monitoring of the performance improvement has been tracked where the runs are rated against offsets. The rating is in terms of overall run performance, footage improvement, ROP increase, cutting structure condition, and overall dull grade. The new bits set over 30 new benchmarks.

Egypt Western Desert drilling fields have been known for harsh drilling environment, shock and vibrations conditions, interbedding and abrasive formations. Drilling assemblies have normally been suffering from excessive damages drilling through these conditions. Motorized rotary steerable drilling systems (RSS) were mostly considered the favored mechanism of drilling in this environment as they delivered higher drilling performance and mitigated vibration harmonics from transmitting higher up the string. Realtime shocks and vibrations data from directional tools was critical information to ensure safe and efficient drilling parameters and managing this harsh drilling environment without operating the equipment beyond its specifications. In a recent western desert well, Khalda Petroleum Company (KPC) endorsed a new drilling strategy by modifying the conventional motorized rotary steerable drilling assembly from having only the RSS below the motor to having both the MWD and RSS tools below the motor. This modification was designed to enable KPC get closer measurements to bit with full transmission of all downhole data to surface to optimize the drilling parameters. The modification also aimed at increasing the bottom hole assembly (BHA) stability to prolong the run duration. To ensure reaching this goal, the design phase focused on two main directions. First, multiple finite element analysis modeling was implemented to ensure the optimum BHA stability and resistance to shocks and vibrations conditions. Second, KPC took needed considerations on the mud motor design, RSS operational procedures and MWD setup to ensure that these would fit properly in the new BHA design. The strategy implemented has shown great success in delivering the section safely and with no incidents related to downhole drilling uncertainties and conditions. The section delivered the required directional profile with great precision and adherence. The new BHA actual data has shown high conformance to the modeled data and no shocks and vibrations conditions were encountered. The section was drilled in one run and was considered the longest and fastest directional run in its field. This has eventually lead to delivering this milestone section 3 days ahead of its planned timing.

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