bluuebunny/crossref_metadata_2025_split huggingface dataset:
Planning and Execution of First Underbalanced Coiled Tubing Drilling in Adnoc´s Fields Utilizing First Successful Closed Loop System Globally
Authors: Osama Mohamed , Sumaida Ali Sulaiman Bin , Shahat Ayman El , Mutawa Ahmed Al , Almazrouei Saeed , Saleh Abdalla , Yousfi Fawad Zain , Almteiri Nama Ali , Baslaib Mohamed , Mantilla Alfonso , Deshmukh Rohit V. , Solaiman Tarek , Abdulsallam Fouad , Ladmia Abdelhak , Rangel Pedro , Rennox John , Cui Shuai , Jumagaliyev Yerlan , Basha Maged 
Published: May 2023

Abstract
The Operator planned and conducted Underbalanced Coiled Tubing Drilling (UBCTD), operations on 3 wells in Operator Onshore fields targeting tight sour gas carbonate reservoirs. The objectives of these operations were to evaluate the applicability of the technology in these fields, to understand requirements and methods of the technology and to evaluate the benefits of drilling the target formations in an underbalanced mode.
As a preliminary step, the Operator conducted a feasibility study that flagged potential limitations to deploying UBCTD operations in existing wells, due to limitations on the completion design and other factors. All of this resulted in the plan to drill fit-for-purpose wells to the top of the reservoir to facilitate the deployment of the technique. These wells were completed with 5.5/4.5 in. Tubing and 7 in. Liner and left with a 100ft open hole interval from where CT drilling operations would later continue. The results of the feasibility study notwithstanding, additional detailed engineering work was performed in all aspects of the design by the operations team to ensure the success of the trial, including a review and validation of the available data and the feasibility to deliver the stated objectives (lateral length, underbalanced conditions, minimal flaring operations, drilling fluid re-circulation, etc.).
As a result of this approach, all three wells were successfully drilled in underbalanced conditions and to the target lateral length of 4,000 ft. Well placement was facilitated using Biosteering techniques and continuous monitoring of the well performance vs. drilled footage, allowing steering decisions to be made in real-time to maximize the production of each lateral, resulting in outstanding production results of 3x the productivity of similar wells drilled conventionally, (after stimulation).
This paper will detail the design process highlighting key engineering decisions and assumptions taken during the design process and comparing them to the actual behavior of the well and the impact of real-life constraints on the operational parameters. The base design and lessons learned from the project will serve as a launching pad for planning and efficiency gains for future UBCTD operations.
Selection of Tool Joint Material and Connection for Drilling Tubulars in Sour Service Environments
Authors: Awad A. , Aydin M. , Hehn L. , Jaber A. Q. 
Published: May 2023

Abstract
The torque requirement for sour service drill pipe connections has always been a drilling challenge. Operators and contractors face challenges when selecting the appropriate tool joints to use in a sour environment, especially when combined with deeper or longer wells.
Depending on the severity of the sour service environment, which is defined by the Association for Materials Protection and Performance (AMPP) [formerly National Association of Corrosion Engineers (NACE)] MR0175-2015 severity diagram, where environmental severity is defined in regions (0, 1, 2, and 3), several studies have been carried out to understand the actual limitations of the tool joints based on each connection design and tool joint material grade and not a "one-size-fits-all" approach (Plessis, 2022). A research and development (R&D) and industrialization test campaign was started to confirm the connection technology performances and limitations in each sour service environment.
Original equipment manufacturers (OEM) provided various tool joint material grades and connections technology to address drilling engineers’ specific needs for sour service environments. For example, a drilling engineer may require an increase in the maximum torque in the connection. This led to some exotic developments in double shoulder connections (DSC) technology, with thread designs other than the API standard for rotary-shouldered connections. Depending on the sour service region for the drilling operation, newer DSCs allow additional torque without compromising the sour service resistance features. The limited availability of high strength and sour service resistance standards added pressure on OEMs to innovate new grades. The drilling engineers demanded that these grades be able to drill deeper and longer wells. In addition, they wanted to customize tool joint grades to fit into the needed drill pipe.
As the drillstem technology leader, we saw an opportunity to drive this initiative and offer a sour service resistance suitable for each region, depending on severity. This allows operators to reach the maximum limitation a tool joint can offer based on its tensile strength and connection design.
How to Comply Ai Generated Data with Wells Hse Performance Procedures and Requirement in Practice
Authors: Shirkhorshidi R. , Norazman N. , Rosli M. B. , Arriffin M. , Karbasian M. 
Published: May 2023

In recent years, many companies have deployed AI-based monitoring systems to detect unsafe act and conditions on industrial setups in real time. Although such technology has proven its capability, the industry hasn't shown a rush toward its usage as what we experienced on (e.g., ChatGPT). This fact shows that using AI integration into closed circuit television (CCTV) cameras alone is not enough to maximize such technologies in industrial setups and processes despite their huge development.
An offshore drilling rig has an extremely harsh working environment, which involves people of a wide variety of professions and cultures. Therefore, any solutions that aim to mitigate risks there must engage all sectors and stockholders, be based on existing culture and comply with current procedures on rigs. This is neither an easy nor an impossible mission.
A key objective of this practice was to build an AI-based platform that would not only benefit end users in various levels and prove the technology capability, but also deliver values. Therefore, to create the most efficient AI-based platform for everyone, cutting-edge noise reduction technology, risk assessments, and technology capabilities were aligned with existing safety procedures, reporting systems, and management cultures.
Implementation of a Permanent Well Barrier Across Triple Casing 7-Inch × 9-5/8-Inch × 13-3/8-Inch Casing in Record Time for the Customer, Saving 4.4MMUSD and 17 Days of Rig Time
Authors: Khan Muhammad Zafar , Jofri Ali , Swadi Shantanu , Ali Hammry , Najmi Nik Fahusnaza
Nik 
Published: May 2023

Abstract
This paper discusses challenges in section milling operation for three strings of casing configuration across the cap rock, to enable a zonal isolation for a well that was drilled in year 1980. A high ratio section milling (HRSM) technology was successfully implemented to deal with this complex well that had all the casings cemented to the surface, together with centralizers for each joint to prevent a simple cut and recovery of casings. The conventional operation on the other hand would require the cutting and pulling of the inner casing, followed by casing milling of the long string of inner casing.
The new HRSM technology eliminated excessive casing milling operation which is conventionally required to access two or three strings of cemented casings prior to place a well barrier. The HRSM technology has a high expansion ratio to enter small restrictions coupled with 6-point active stabilization to counter dynamic loads and vibration when section milling. The operations challenges were optimized using the standard section mill assembly, a high ratio underreamer designed with casing scraper arms and the newly developed HRSM with new arms for the 3-string configuration.
As part of the planning phase, identifying the depths for inner and outer milling were considered along with the placement of couplings and centralizers which is crucial for milling operation. Once the window plan was completed, a thorough BHA vibrations analysis was carried out followed by a comprehensive hydraulic analysis to identify key parameters for milling and mud rheology for the entire operation.
One of the key challenges during the execution phase was the milling the centralizers on each joint of 7-inch and 9.625-inch casing. The operation was initiated by milling in the inner 7-inch casing in two stages. First the cut out of 7-inch casing was initiated followed by flush knives to mill the casing and creating a 34.7m window to access the 9.625-inch casing. A high ratio underreamer was used to clean the cement sheath in 9.625-inch casing before the new HRSM technology was run to section mill a window of 24.15 meters in 9.625-inch casing. The new HRSM was specifically designed with new cut out and flush knives to mill the 9.625-inch casing inside 13.3.75-inch casing. The final clean out of 13.375-inch casing was completed by newly designed scraper arms for the high ratio underreamer thus providing a solution of restoring the caprock across 3 strings of casing.
The unique design of HRSM technology led to the completion of first of its kind application by restoring caprock across 3 strings. This niche job has been able to save the client significant rig time for its plug land abandonment operations.
A New Mechanical Tool and Method to Accessing Casing-Casing-Annulus to Remove Compromised Cement and Injecting a New Sealant
Authors: Machocki K. , Alshaarawi A. , Alsheikh M. 
Published: May 2023

Abstract
This work presents experimental studies on a new tool concept to address casing-casing-annulus (CCA) pressure leak challenges in the drilling industry. The new method uses an intervention-type tool that allows for exiting the casing, cleaning cement behind, and injecting any required sealant to block fluid migration on the annular side. Addressing such CCA challenges is essential for increasing the production time and maintaining wellbore pressure integrity.
A combination of 3D modeling and experimental studies is used to evaluate the feasibility of the new concept for addressing CCA fluid migration challenges. This study focuses on the development and evaluation of a tool that allows accessing and sufficiently cleaning cement in multiple CCAs. We have successfully tested a scaled tool. This tool can punch a small hole in a casing at a unique angle and clean cement behind it by drilling spirals on the annular side.
The new method for accessing the annular side of the casing and cleaning cement behind it has been developed and successfully tested using scaled model rigs. Studies have involved an early proof of the concept in plastic and steel. We have also simulated cement with fluid communication channels behind the casing with a successful attempt of removing it.
The experimental test results are being used to further develop a robust, downhole field-deployable tool and method that captures the essential features required to access and operate in CCA areas. The current study suggests that a significant section of cement can be removed by the proposed method: One small-diameter hole is drilled in the casing, and then a cement removing assembly is run in a spiral motion on the annular side of this casing. A suitable sealant can be injected in the created void in cement to stop potential fluid migration.
This experimental study suggests that the CCA can be accessed and resealed with a minimum time and equipment if required.
This CCA milling-injection system (patent pending) utilizes a novel, easily-deployable tool. This tool enables milling access into the annular side of designated casings, and enables cleaning the cement behind it. The new system only mills one hole in the casing limiting its damage and providing the ability to clean a significant section of the cement at the desired depth. This helps address potential CCA leaks, saves time and cost.
Disruptive Plug and Abandonment Technique Using Bismuth Alloy for Offshore Operations Enhancing Sustainability
Authors: Kuyken Chris , Carragher Paul , Talapatra Didhiti 
Published: May 2023

Summary
The bismuth alloy technology is capable of permanently and eternally shutting-off gas migration in single or multiple casing annuli by forming a V0 rated Metal-to-Metal gas tight seal. For P&A operations the bismuth alloy barrier technology results in a significantly higher level of sustainability compared to the current conventional way of performing P&A operations in oil and gas wells. This requires to be acknowledged in the vision for the future of P&A which will be one of the most emission intense oil and gas activities.
This paper will explain results of recent P&A campaigns that support the above fact. Bismuth alloy barriers were deployed inside 12 section milled windows of less than 50 feet length in a recent campaign for an operator in the Middle East. The wells were successfully P&A- ed, building on a track record of a worldwide P&A campaign with the "Seal Through Casing" bismuth alloy technology with about 160 wells executed between 2015 and 2023.
The reason for the eternal barriers is related to the unique and unmatched physical barrier performance properties of bismuth. Bismuth, in its molten form, which is melted downhole using the energy generated by the thermite heater, has the viscosity like that of water (1 – 3 cps) and a specific gravity of around 10. Which means it is about 10 times heavier than water. This allows it to flow freely in all directions - into section milled windows or through perforations, crack, crevice, or micro annuli displacing any fluid in its path (Fig. 1). These bismuth alloys are eutectic in nature which means one of the properties that they exhibit is they change phase at a single sharp temperature without passing a two-phase equilibrium, i.e. liquid and solid state. Another unique property of elemental bismuth and bismuth-based alloys is that it expands on solidification, like water as it solidifies into ice. In case of pure bismuth and bismuth-based alloys this volumetric expansion ranges between 1% – 3% depending on the composition of the alloy. Bismuth based alloys once molten can thus flow into any volume or annuli and take its shape and once solidified it expands against the casing, cement or formation creating a V0 gas tight barrier.
These unique physical properties combined with high corrosion resistance nature make bismuth-based alloys the ideal candidate for long term "eternal" P&A material.
Study on Anti-Corrosion Performance and Applicability of Self-Healing Coating for Tubulars in CO2 /H2S Environment
Authors: Wu Bohong , Qiu Ping , Shi Shuzhe , Zhang Yanna , Huang Xueqin , Nie Zhen 
Published: May 2023

Abstract
In a Middle East oilfield, reservoirs are characterized by high temperature, high salinity, high CO2 / H2S content, and low pH, which leads to harsh corrosive environment. With development of the field, the increasing water cut and application of CO2-EOR technology have made tubulars face greater corrosion risk. Therefore, employing feasible anti-corrosion coating to corresponding part is one of the most effective technologies to mitigate downhole corrosion risk, reduce workover, and avoid potential HSE risk.
Corrosion environment characteristics was thoroughly studied by reviewing production history, water chemistry, gas composition, downhole temperature and pressure, logging data, etc. Downhole corrosion condition was classified based on NACE standard RP0775-2005. Based on this, the field simulated corrosion tests were carried out on the self-healing coating in high-temperature and pressure autoclave. The self-healing coating was fabricated by loading slow-released MBT-LDH nanocomposites to the phenolic epoxy resin. For comparison, the similar experiment was also conducted on commercial phenolic epoxy coating and heavy-duty coating. The anti-corrosion performance and applicability of the coatings were characterized by SEM/EDS, FT-IR and EIS.
Two main factors have been considered while evaluating the coating options, the first consideration is reliability and durability of the coating. If the coating is easily damaged during operation and transportation, its protective performance decreases after damage, which cannot be easily repaired again. The second consideration is the compatibility of the coating in a harsh downhole environment. Considering the above aspects, the self-healing coating, commercial phenolic epoxy coating and commercial heavy-duty were selected. After corrosion tests, a small amount of corrosion products can be observed on the commercial phenolic epoxy coating surface both in the simulated well head and bottom condition. There were no obvious morphology changes on the heavy-duty coating surface in both condition, however, chemical degradation of the coating was observed in well bottom condition. Notably, the self-healing coating appeared no peeling, bubbling and other defects in both conditions. There were corrosion products identified in the pre-destructed area of the coating, which attributed to the localized inhibition of the self-healing coating.
This paper investigated the corrosion resistance coating technology, including coating selection evaluation, typical tubing thread area protection technique, coating chemical and physical property analysis and evaluation. The study also recommended coating applicability for the target reservoir. The results suggested that phenolic epoxy based self-healing coating show robust anti-corrosion performance and can be used in the downhole containing CO2 and H2S.
The Development and Application of Ultra-Short Radius Lateral Drilling Technology in Low-Permeable Reservoir of Western South China Sea
Authors: Huang Yi , Liu Hexing , Liu Zhiqin 
Published: May 2023

Abstract
L2 formation of X Oilfield in western South China Sea is of characteristic of low porosity, low permeability and well controlled reserves, and long well interval, drainage area and controlled reserves can be significantly increased by adopting ultra-short radial radius drilling technology. Flexible drill pipe and drill bit was used in Well WZ-X1 to perform kick-off operation with only 2.4 m footage to increase inclination from 37 °to 87 °, and hold its inclination by drilling 60-62 m alongside reservoir with trajectory control margin of ±2°. This paper highlights the trajectory control technology with research of BHA, build-up and hold drill bit, and accurate calculation. During the field operation, drilling parameters were adjusted on the basis of formation variation and outstanding trajectory effect was accomplished and ultra-short radial radius trajectory control technology was achieved. This technology can solve the problem of trajectory control and extend horizontal section of reservoir. It can increase wellbore drainage area and well control reserves, providing technical reference for future operation.
Understanding Drilling Dynamics Thru Tandem Downhole Recording Tools Enabled Drilling Performance: Middle East Specific
Authors: AlHosni Fahad , Echevarria Edgar , Ruzhnikov Alexey , Rojas Luis 
Published: May 2023

Abstract
Drilling the 12.25-in. landing section in one of the Middle East fields had been a challenge in terms of drilling performance due to combined downhole severe drilling dynamic mechanics effects and borehole instabilities. These complications eventually lead to downhole tool failures and a low rate of penetration (ROP). This manuscript describes the solution to introduce tandem downhole dynamic recording tools in the Bottom Hole Assembly (BHA) which provides a better understanding of the downhole dynamics and mechanics effects guiding to optimum BHA design and leading to better performance.
Drilling the curve and landing section is challenging due to extreme stick & slip (S&S) and shocks & vibrations (S&V) phenomena resulting in low performance and difficulties in achieving the directional requirement. The 12.25-in. landing section is drilled with a full set of Rotary Steerable System (RSS) drive, Positive Displacement Mud Motor (PDM), Measurement While Drilling (MWD) and Logging While Drilling (LWD) tools, making the BHA very rigid. Nevertheless, many initiatives have been carried out to enhance the BHA and bit design with limited improvement. After performing a detailed risk analysis, tandem downhole dynamic recording tools were introduced to understand the downhole dynamics behavior and the interaction between the bit, the drilling BHA components, and the different formations drilled.
The downhole dynamic recording tool is powered by batteries and records the data in memory mode for post-run analysis. It measures downhole drilling mechanics with its three-axis accelerometers, gyro, and temperature electronics along with other measurements. The downhole recording tools was installed tandemly across the 12.25-in. motorized RSS BHA where one tool was positioned inside the bit and another one in a sub above the mud motor. After the run, all the data from the two downhole recording tools were downloaded and then analyzed. From the recording tool at the bit, it can be concluded that the PDC bit used in the analyzed run, generated low-to-medium stick & slip, hence, a new bit design with more aggressive features could be used safely to enhance the ROP. From the recording tool in the sub above the mud motor, it was concluded that the BHA components and mainly the LWD tool created high-to-severe stick & slip due to its stabilizers, and action should be taken to minimize this effect. In addition, the drilling fluid lubricity needs to be enhanced to reduce the stick & slip and shocks & vibrations effects on the tools. All the presented solutions and lessons learned of the downhole dynamic recording tools utilization can be used for future run enhancement and to be replicated worldwide as applicable.