Drilling the deep lithology column using PDC bits in the Obayied field of Egypt's Western Desert has been extremely difficult. The field's lithology column represents an amplification of all of the typical lithology characteristics in the Western Desert. The highly interbedded sandstone, siltstone, and shalealong with the variance of such interbedding across the field-has been a significant challenge for well planners and has adversely affected cost per foot. The application is characterized as predominantly abrasive and impact-intensive in the same section, hence challenging for PDC bit durability. To efficiently drill the 8½-in interval, a fundamental change in PDC bit design is required.Considering these formidable challenges, service providers had to evolve PDC bits to meet the constant demand of improving performance and reducing costs. Focus was concentrated on balancing new technology developments and the willingness to invest on field trials. To accomplish these objectives in the Obayied field, the operator and the service provider identified two main problems-developing an in-depth understanding of rock strength characteristics of each individual formation in the deep rock column and its variance across the field, and developing PDC bits that can survive such a challenging rock column with improved durability and ROP.Recently, a novel conical diamond element (CDE) with extreme impact-and abrasion-resistant characteristics has been developed. The CDE has been incorporated at bit center in a new and innovative PDC design, solving the traditional challenge of the inefficient characteristic of PDC bit central area. In addition, a field-wide rock strength study based on sonic and gamma rays logs provided the transparency required for better planning and risk management to resolve the operational inefficiencies traditionally seen in the Obayied field.The new PDC bits utilizing the CDE technology has been deployed in Obayied and has reduced consumption to just 3-4 bits per section in 2014, whereas that number was 8 -10 bits per section averaged in 2006. The new bit has also reduced the average number of days to drill the section from as low as 6 days to reach TD instead of 20 days. Performance gains were achieved both in ROP and footage totals in the most challenging formations, including Alam Al Buwaib, Upper Safa, and Lower Safa. The authors will discuss the benefits of this industry collaboration that achieved exceptional performance improvement leading to dramatic cost savings in the Obayied field.

The 12 ¼" section in the western desert, Bapetco concision is challenging to be drilled as of the highly interbedded carbonate and shale formations, which are known to exhibit high levels of vibrations (torsional and lateral) associated with high drilling torque. Such high drilling torque lead-to increasing the Mechanical Specific Energy (MSE), reduction in Rate Of Penetration (ROP) and early dull for used bits. While in some cases it can even lead to twist-off incidents and major Non- Productive Time (NPT) events. Customer NPT can cost up to $ 450k in case of sidetracking the well. In case the Bottom Hole Assembly (BHA) stands the vibration level, the parameters would have been controlled losing ROP which resulting in lost time that cost at least $ 35K. The solution of adjusting the depth of cut downhole (Self-Adjusting) which have been newly introduced to the market targeting to decrease downhole vibrations, specially torsional vibrations and allow smoother transition between lithologies with different compressive strength and help in a smooth transition between the different layers while optimizing the depth of cut control When the self-adjusting feature engages with rock for steady state drilling, the feature gradually retracts, controlling DOC to find the optimal exposure of the element for the current drilling parameters and formations. As dynamic instabilities occur, the self-adjusting feature reacts at fast time scales to mitigate the event. This should result in optimizing the bit response to deliver the best performance real time, decreasing the torsional vibration, NPT & MSE. This will lead to increase the drilling efficiency. The 12 ¼" PDC bit with the self-adjusting was tested with one Shell/Bapetco in the western desert wells, resulting in decreasing the vibration levels, decreasing the MSE hence increase the ROP 57% compared to average of the field which resulted in significant reduction to the drilling cost compared to the offset wells while achieving 35K of savings compared to the best offset Below will present how the latest self-adjusting PDC technology had a significant impact on drilling time and cost savings by mitigating drilling dysfunctions that could result in unplanned trips and drilling inefficiencies if not addressed in a timely manner