With an objective to shorten directional intervals, operators place greater demand on higher Build Up Rates (BURs). The section just before the pay zone involves the most intensive directional work, pushing rotary steerable systems to their capability limits. This paper focuses on a particular interval of hard and soft interbedded carbonates that provides a significant challenge for conventional Polycrystalline Diamond Compact (PDC) bits to provide consistent build up rate and good borehole quality on rotary steerable systems. Throughout this paper we demonstrate the engineering process of designing a bit to increase buildup rate capabilities of rotary steerable systems and improving drilling efficiency through interbedded carbonate formations. The engineering process involved reviewing the critical issues of this application to assure a sound solution. This included: Current build up rates versus Rotary Steerable Systems (RSS) steering capability. Vibrations generated by conventional PDC bits being deployed in the field. Specific cutting structure, depth of cut limiters and gauge requirements for different RSS drive types. Formation strength analysis. Parameters used in drilling the section. Roller cone insert and PDC interaction of the hybrid bit with the formation and how formation deformation generated by one interacts with the other. Roller cone insert design aimed specifically at carbonate formation drilling Various hybrid drill bit and Bottom Hole Assembly (BHA) combinations were evaluated with state-of-the-art drilling response simulator to review the buildup rate capabilities combines with the bit and BHA interaction. The best combination was then successfully trialed on several wells, proving significant improvement compared to current performance with conventional PDC bits. The optimized hybrid bit and BHA combination eliminated drilling vibrations in intervals where extreme vibrations were witnessed with conventional PDC bits, significantly increasing drilling efficiency. Improved torsional stability reduced the load on the directional tools improving the ability to achieve the required doglegs. In softer shale where RSS with conventional PDC's had to control parameters while using maximum steer force to achieve target dog legs of 7°/100ft, the hybrid drill bit achieved 10°/100ft while utilizing only 70% of the steer force. The hybrid drill bit has been proven to be successful with both push-the-bit and point-the-bit RSS systems. Hybrid drill bits have proven to be a solution to problems and limitations of both conventional PDC and roller cone bits in directional drilling. Based on recent refinements in the drilling mechanics of hybrid drill bits to further improve their interaction with directional drilling systems, engineering selected this emerging technology to overcome the challenges in this particular application.

X-Y positioning is an important task in industrial applications, as this system is used for welding, cutting or for pick and place applications. The studied X-Y core positioning system is a parallel X-Y position device, which due to less moved masses is potentially capable of fast acceleration and therefore faster positioning than traditional stacked systems. A kinematic model of X-Y core positioning system is derived, which used for accurate position control in X-Y stage of the cart using low cost stepper motor and low cost controller (Arduino Mega2560). The proposed design of X-Y core positioning system which has 8 pulleys and two open ended derive-belts and have the double size of all designs that introduced in this field has its advantages of fast design, simplicity and flexibility. The system is very much simple, rugged, and cost effective. The experimental results show that the proposed system has a high resolution, repeatability and error is within acceptable limit. The proposed strategy used to control positioning in X-Y stage enable accurate cart positioning with max error percentage less than 5%.

In the prolific North Kuwait field, the 16 inch intermediate vertical section is typically drilled with Tungesten Carbide Insert (TCI) drill bit [445 IADC] and rotary assembly. The TCI average Rate of Penetration (ROP), through approximately 4,800 feet of limestone, sandstone and shale, is 38.7 feet per hour. Given the operator's target to reduce drilling time and minimize the North Kuwait well cycles; the hybrid drill bit was proposed to raise ROP performance and save drilling days per well. The main challenge was to significantly reduce drilling time and enhance the cost-per-foot of the application with the new hybrid drill bit. In addition to providing smooth torque fluctuations, similar to that of the roller cones drill bit. A specialized Drilling Application Review Team (DART) from the service provider implemented an optimization process to achieve the aforementioned targets. The hybrid bit design has been revised and upgraded to best-fit the interbedded carbonates application. Bottom Hole Assembly has been modeled and optimized by the cross-functional engineering team and the client to ensure best torque response while drilling. Moreover, a detailed formation drilling analysis has been conducted to accurately anticipate hybrid bit ideal case. The optimized hybrid drill bit set the highest ROP record, at 80 feet per hour in North Kuwait achieving 107 percent improvement from offsets’ average performance. Moreover, the optimized design delivered 2 and a half days savings when compared to field offsets by conventional technology. The selected system generated smooth torque response and hence high energy efficiency. This success has been repeated over multiple wells in North Kuwait project; proving consistency in technology value.

Optimised drilling performance requires matching the right drill bit technology to an application, which can be an engineering challenge. Hybrid bits provide versatility in drill bit selection that was previously not possible with conventional drill bit technology, allowing for a broader range of applications. This paper details the results of a case study where polycrystalline diamond compact (PDC), tungsten carbide insert (TCI) and hybrid bits were tested in the same application in an attempt to improve drilling performance. Each drill bit type has its strengths and weaknesses, and is therefore suitably matched for specific applications. Sometimes, a specific technology matches well to the application, and it is the ideal solution; however, there are many cases where the ideal drill bit type isn't so clear. Hybrid drill bit technologies produced a new generation of bits. These bits reduce the difference between specific bit technologies, enabling them to outperform either type in demanding applications that require strengths from each technology to drill successfully. A non-homogeneous carbonate formation that was prone to causing impact damage challenged conventional drill bit technologies. The 12.25–in. hole section was drilled vertically on a rotary bottom hole assembly (BHA). Initial trials with PDC bits showed that the bits suffered significant impact damage, preventing them from completing the section or reducing their drilling capacity so the rate of penetration (ROP) dropped below TCI performance. The TCI bits drilled relatively slowly, and although they were more durable, they also suffered impact damage. Hybrid bits were tested on this project to leverage the benefits of each technology and improve drilling performance in this section. This hybrid technology achieved outstanding results in the South Ratqa field. In multiple deployments the hybrid drill bit doubled the ROP compared to conventional technologies. The benchmark performance reached by the hybrid drill bit was triple the ROP of conventional technology. The trial saved the operator up to 3.5 drilling days and more than 70% of the drilling cost for this section.

In the prolific Burgan field, South East Kuwait, new well profiles are being employed which require the 16 inch hole section to be drilled deeper. This new well profile requires drilling through interbedded abrasive sandstones and sticky shale which were previously drilled in 12 ¼ inch hole size. Drilling becomes increasingly challenging using larger diameter bits where torque fluctuations, down-hole conditions and durability limit performance. As the casing profiles changed, each section's drilling solution was revisited as drilling dynamics and performance diminished drastically when drilled in the larger hole size. What was once a viable solution to drill the section in 12 ¼ inch becomes no longer suitable when drilled in 16 inch. The purpose of this paper is to demonstrate the engineering analysis for large diameter hole application and the selection of an optimized hybrid drill bit design, roller cone combined with Polycrystalline Diamond Compact (PDC), to maximize drilling performance where standard PDC or roller cone bits alone fail to provide an optimal solution. The 12 ¼ inch section was typically drilled using a rotary bottom hole assembly with a roller cone bit or using a performance mud motor with a PDC bit. Drilling parameters were reduced in the upper layers especially with PDC bits as they involve sticky shale which can induce bit balling. While in the lower layers the abrasive formations tend to wear down roller cone bits. Combining the benefits of both bit types, a 16 inch hybrid bit was proposed to answer the challenge of drilling the section as fast as a PDC bit while providing the stability, torque control and smooth hole condition generated by a roller cone. Selecting an appropriate hybrid design to match the application resulted in an initial trial of a durable hybrid bit that finished the interval with virtually no wear on the bit and significantly improved borehole quality. The second trial of the hybrid bit with a modified, more aggressive design approximately doubled the ROP of a PDC bit while maintaining a smooth hole profile and minimizing torque. PDC bits generally provide faster rate of penetration than roller cone bits while generating higher torque fluctuations as they drill by shearing bottom hole formation. Due to their high torque demands, PDC bits require an additional mud motor to drive them efficiently in larger hole sizes. Roller cones crush and gouge the bottom hole formation and due to their mechanical rollers result in reduced reactive torque and a smoother hole profile. Hybrid drill bit technology proven the capability of achieving the benefits of both designs in specific selected applications.