Abstract This paper describes the implementation of the Drilling Automation System, which has been initiated to control and enhance the drilling performance. The automation system fully controls the drilling parameters and surface rig equipment to improve the drilling Rate of Penetration (ROP) and mitigate drilling challenges. The results were measured systematically and compared to the manual rig operation benchmark. The Drilling Automation System was integrated into the rig control system during the rig manufacturing process, then deployed and configured upon spud drilling operation. The system controls the Top Drive System (TDS), drawworks, mud pumps, and auto-driller by augmented intelligence. The system -when enabled- intelligently controls drilling parameters and surface equipment by creating a model of how the formation reacts to each drilling parameter along with segmenting the input of the engineering team to optimize drilling ROP, automated downlinking, and surveying for trajectory control, and optimize pre and post connection times. Additionally, it mitigates stick and slip, shocks and vibrations, and high erratic torque, which elongates the durability of drilling tools. On the field level, a comprehensive drilling performance data analysis has been conducted to get an accurate comparison between manually operated rig performance and rigs with an integrated automation system. Close monitoring of the improvements in drilling performance, avoidance of hidden Non-Productive Time (NPT), overcoming drilling challenges, more downhole tools durability, and smooth directional drilling performance. The automated rig outcomes proved the success and capability of achieving higher Key Performance Indicators (KPIs) and benchmarks than manually operated rigs by an additional 33%, with a possible window for future enhancements. The Automation System is beneficial for automating surface equipment; however, the great output comes from the automation of the driller's decisions with full procedural adherence. Automating the drilling process with a synergy between surface and downhole tools is the future. The system's immediate response to downhole conditions minimizes drilling issues without human interaction. The result seen in this experiment shows a promising future for implementing this technology with flexibility for further upgrades.

Abstract Managed Pressure Drilling (MPD) helps operators excel in efficiently navigating through narrow pore pressure- fracture pressure windows avoiding any induced losses due to extra overbalance with conventional mud. The case study highlights how these challenges were mitigated during drilling as well as post drilling operations including Reaming/Cleanout Trip, logging & Cementing Casing with the implementation of a fully automated MPD system, saving thousands of barrels of mud losses. Case-study well −1 describes a corrective approach where major losses circulation was rescued by timely displacement of well to a lighter mud precisely using MPD technology while maintaining well control, following a modified displacement table. Cured losses, restoring full circulation with no background gases after full cycle & resumed operations, hence saving expensive oil based mud-losses costs, despite of several challenges including extended lateral and high background gas percentages. Case study well-2 describes a preventive approach where the objective of MPD was to manage the equivalent circulating density (ECD) through narrow window by adjusting the mud density, mud pump rate, MPD surface backpressure or a combination of these parameters during post drilling operations like reaming, logging and cementing. The target bottom-hole pressure was adjusted almost instantly and precisely by adjusting the surface pressure at the MPD choke, thus greatly reducing the time to stabilize well conditions in case of any well control or if downhole losses are encountered. MPD enabled reaming operations with max pump-rates, hence better hole cleaning without the hazard of downhole mud losses. Recently, the MPD Constant Bottom Hole Pressure (CBHP) technique was successfully implemented by one of the biggest operators to drill and complete gas wells through an unconventional field. After reaching total depth by drilling using MPD technique successfully, it was decided to perform logging operations conventionally with the kill mud. But after going deeper while logging, partial losses were encountered. To rescue the situation, decision was made to switch to MPD mode, regaining full circulation. The narrow drilling window was exacerbated by the increased in annulus frictional losses, in particular for the post-drilling operations like reaming which required a high pumprates, hence high ECD and casing cementing operation for these long horizontal wells which again lead to high ECD. So, leveraging the extensive experience in MPD, the CBHP technique was extended to the reaming and casing cementing operation, maintaining the downhole cementing ECDs within the prescribed limits. This paper highlights the pre-planning, on-site planning, execution and post-operations phases of the Managed Pressure Cementing (MPC) operation, which allowed the operator to perform a successful reaming trip and cement job utilizing the MPD-CBHP technique, for the first time in the field. Lost circulation is a concern during not only drilling phase. If post drilling operations like cementation are performed with full circulation utilizing MPD technology, this adds to a better casing cement integrity. By proper planning most induced lost circulation can be prevented with MPD technology.

Abstract The exploitation of LQR (low-quality reservoir) required advanced technology due to its difficulty to produce. The asset optimization team focuses on improving oil recovery from low quality shaly sand reservoir as the remaining reserve is attractive with typically low recovery factor only 22%. The horizontal well has been found as the best method to exploit remaining oil in LQR in Rocky Block. Waterflood North Area consists of 12 fields and maintains more than 178 horizontal wells. There are many challenges in horizontal well that leads to poor oil production performance. It’s found that low productivity in horizontal wells is caused by formation damage. Many factors contribute to its such as solid particle plugging due to poor lateral clean-up job at well initial completion and scale build up as an impact of utilized calcium carbonate mud drilling base and nature of water. A combination of RE-LCU (Re Lateral Clean-Up) and rotary high pressure jetting acidizing strategy might as a potential solution to improve productivity index of horizontal. The CleanUp-JetAcid method introduce a breakthrough to improve stimulation job success ratio in horizontal wells by providing excellent multi disciplines analysis at early phase of well candidacy process workflow until final execution process of RE-LCU and combine with rotary high pressure jet acidizing as technology available in market. New workflow of RE-LCU candidacy process established to improve understanding of horizontal well production performance within geology framework and leverage integration analysis among discipline to ensure all data are maximize use to solve problem. This workflow is designed to minimize uncertainty and risk in the early phase of screening horizontal wells and meets with root cause of low PI due to formation damage. To be able viewing the opportunity of RE-LCU in wider scale involving all fields in Rocky Block, then implementation of new workflow is completed as one standardized workflow process in reservoir level respective to reservoir management to identified higher quantity of wells candidate. A comprehensive effort through CleanUp-JetAcid method has been made to solve low productivity index issue in horizontal wells. Some significant impacts have been achieved from 2 pilot wells execution have successfully delivered 38.6 MBO. Many parameters shown outstanding improvement; Success ratio of RE-LCU stimulation increase to 100%; Oil gain increase 364% with additional Fluid rate improve almost 300%, the degree of RE-LCU job quality is excellent, turbidity of fluid is less than <90 NTU that never been achieved before compared to previous method. 49 more horizontal well candidates have been identified and reviewed as a part of expansion program. Replication of this method might as an opportunity to be implemented in old horizontal wells that have similar problems to improve oil production horizontal well.

Abstract The simulation of the process of plugging slurry sealing fractures through indoor experimental methods presents a convenient and efficient approach for the selection and design of lost circulation materials (LCMs). Nevertheless, prevalent plugging experimental apparatuses exhibit limitations, including a small fracture plate scale and reduced reproducibility. To address the limitations of the currently utilized plugging experimental devices, a wellbore-fracture coupled plugging experimental device is employed to simulate the operational process of wellbore plugging slurry injection. A large-scale visualized fracture plate, fabricated from plexiglass and based on the geometric parameters of formation fractures, is processed. Laser etching technology is utilized to replicate the undulating characteristics of the fracture wall. A sequence of sealing evaluation experiments was conducted, employing commonly used well field materials, including calcite, walnut shell, and flake LCMs. The findings indicate that: (1) The selection of the particle size of the bridging material, based on the D90 bridging principle, employs the particle size selection principle of 0.6Wf for irregularly shaped LCMs, and 1.6Wf for flake LCMs; (2) Under the influence of viscous resistance, the denser bridging material experiences a faster loss of kinetic energy within the fracture, resulting in a co-existing "retention" and "residence" sealing mode; (3) When the length of the fiber material exceeds the particle size of the bridging material, it alters the geometric size by enveloping the bridging material, thereby increasing its "residence" probability and enhancing the interception capability of the bridging material; (4) The study provides a detailed depiction of the settlement and migration behavior of irregular LCMs, uncovers the auxiliary bridging mechanism of fiber LCMs within the fractures, integrates the mouth sealing and sealing effect of LCMs, proposes four evaluation indicators of mouth sealing degree , mouth sealing time, sealing efficiency, and sealing strength, elucidates the negative effect rating of mouth sealing, and establishes the absolute bridging addition map version considering the presence of fiber in the bridging material.

Abstract The Controlled Mud Level (CML) MPD technique is described focusing on the development of its utilization. Initially CML MPD was used as an enabling technology holding a Constant Bottom Hole Pressure (CBHP) to "Drill the Undrillable" and to manage losses by adjusting the fluid level according to actual well conditions. Today, the approach is more based upon reducing well cost, improving safety, and increasing production. The CML method creates a dual gradient effect when lowering the riser level. By moving the hydrostatic column towards the seabed, the pressure profiles are lower at shallow depths and increasing towards sectional TD following the same trend common for operating windows. Utilizing this effect enables longer sections to be drilled within narrow, or even negative, margins - in some cases even when drilling conventionally. The result can reduce the number of sections required in well design, thus reducing the well cost. A CML system can use the riser as the trip tank for instant notification of volume changes in the well. Keeping the fluid level below the telescopic joint eliminates effects from rig motion. The detection sensors are positioned subsea providing earlier and clearer notification of volume changes. In addition to the volume control for all operations, tripping in and out also becomes a safer and faster process without spending time on displacements, by adjusting the riser level to mitigate the surge and swab effect. For depleted reservoirs the drilling approach can start holding the initial virgin pressure and then reduce the wellbore pressure according to the actual degree of depletion. Managed Pressure Gravel Pack has become an established approach ensuring the Alpha and Beta waves go all the way from the toe to the heel without inducing losses. Improving the completion methods and optimizing the execution leads to better production. The development has progressed to where wells are being planned with CML for purposes beyond the CBHP approach. It is used actively in conventional drilling for regular tasks to optimize operations and enhance safety. Since the CML method enables pressure management regardless of pipe size it is utilized for running casings, wireline operations and completion. This paper describes the methodology of the CML technique and refers to field cases to exemplify how this method is used for extending sections, tripping safer and faster, and increasing production through Managed Pressure Completion.

Abstract Back in 2020, a High-Pressure High-Temperature (HPHT) and high CO2/H2S carbonate appraisal well was drilled to remove subsurface uncertainties and to support the future development drilling campaign. The well architecture necessitated the inclusion of two consecutive hole opening sections to ensure optimum casing shoe placements. Along with the demand for long section intervals, the presence of problematic interbedded formation compounded by thick hard stringers added to the challenge for the underreaming operations where cutters durability need to be preserved. High shocks and vibration, Measurement While Drilling (MWD) lost signal, low Rate of Penetration (ROP), and Bottom Hole Assembly (BHA) twist-off were among the challenges and risks that were encountered and led to significant Non-Productive Time (NPT). A final appraisal well for this block was drilled in 2023 which is more challenging due to the deviated well profile. Re-evaluating the lessons learnt from the previous experience, the engineering team from multiple drilling disciplines among the operator and contractor worked closely together to investigate and identify all potential weak points in the planning stage. The aim is to reach Total Depth (TD) for both hole opening sections in a single-run strategy. A physics-based finite element modeling was conducted to study the drilling dynamics of the drilling operation involving bit selections, BHA design optimization, and drilling parameter sensitivity. A much wider range of worst-case scenario modeling was conducted in terms of lithology exposure, and several key technical recommendations were examined and prepared thoroughly to ensure all drilling objectives can be achieved. This extensive collaboration resulted in a comprehensive road map for offshore team to follow through including the contingency scenarios with the close support from engineering team in town. As a result, both 18-1/8in × 19-1/2in and 14-3/4in × 16-1/2in hole opening sections were drilled successfully with an impressive multiple rig-days saving against planned duration collectively. The combined 2,213m depth interval from the two consecutive sections puts this remarkable achievement in the record book as the longest hole opening operations in Asia. This paper will share the experience of the complete engineering cycle from the pre-job well construction planning, drilling dynamics modeling and analysis, drilling parameters execution, also capturing key lessons learnt from the operation and recommendations for similar hole opening application in the future.

ABSTRACT Typical setup for well unloading of oil or gas wells during exploration or appraisal and development phases involved utilization of burner boom where hydrocarbon will be flared off. Flaring would require additional equipment to burn the hydrocarbon, water cooling system, water cooling system to control the heat radiation from burning hydro carbon and accessories related to rigging up burner boom i.e. kingpost and padeye. This requirement would also be subjected to the type of rig being used to support the drilling activities and the existence of the burner boom for the activity to remove additional cost to install kingpost and padeye. For an infill project in offshore Malaysia, three (3) infill gas producer wells were planned to be drilled to extend the field production and hub life above the Turn Down Ratio (TDR). The initial plans involved performing well unloading using the typical well test setup i.e. by installing the burner boom and water cooling systems. A semi tender rig will be used to install the kingpost and padeye prior to the mobilization and rig-up of the burner boom, to reduce the rig standby time. With the vision to achieve zero flaring/venting, even small volume/scale initiatives can be considered as a crucial contributor to this vision. Hence, the unloading plan was revisited, and all options were re-evaluated to ensure that the gas wells can be unloaded safely. Since the field has existing platform and facilities to process/evacuate the gas, condensate and water, the best option was to flow the fluids from the newly drilled wells to the existing facilities. This would eliminate the requirement of the burner boom, kingpost and padeye installations and additional water-cooling system. Evidently, with this option, the team would be able to reduce the project cost significantly and subsequently the hydrocarbon can be produced immediately. This paper covers the detailed planning of the well unloading through the existing facilities which involved equipment spotting, lifting plans, challenges faced during these activities, risks and mitigations and lessons learned that can be replicated in future new infill/development wells while contributing to the zero Green House Gas (GHG) emissions journey.

Abstract Well Plug and Abandonment (P&A) process stands as the primary phase in decommissioning activities. Compliance with country regulations and industry standards is imperative for P&A methods. With over 2,000 wells requiring abandonment post-concession by the Operator, costs extend beyond P&A to encompass waste handling, logistics, scrap disposal, and SSHE concerns. To enhance cost-effectiveness, a novel barrier placement technique, the triple-string cement balance plug, has been innovated, trialled, and assessed. This paper introduces a novel technique, the triple-string cement balance plug, enhancing well Plug and Abandonment (P&A) processes. The primary objective is to establish well barriers across necessary sections via Off Rig operation (Phase 1 using a slickline/electric line and a cementing unit) as much as possible. The procedures for the first and second barriers are similar to Operator's best practices. The additional procedure involves the placement of the third barrier across three annuli. It is achieved by limited penetration perforation and placing a cement plug simultaneously across tubing (2-7/8" or 3-1/2" × 7" casing) and the 9-5/8" casing annulus. Then a well barrier is verified through pressure testing to the required test pressure. The tubing is cut below the SSSV, followed by circulating the well with kill-weight fluid and suspension. Phase 2, by utilizing a Rig/Rigless unit to retrieve tubing, cut and retrieve remaining casing and conductor, if any, and finally the placementof environmental plug. With successful trials during the 2021-2023 campaign and subsequent adjustments, this technique proves successful in perforation, circulation, cement placement, and meeting pressure testing criteria. Implementing this technique anticipates substantial cost savings in the Operator's extensive well P&A operations. Considering the Operator's potential 2,000 wells for P&A post-concession and non-usable wells, this technique could yield total savings of up to 12% for P&A operations alone. Moreover, minimizing the extraction of tubing and casing reduces waste handling, particularly hazardous materials like Mercury, Arsenic, and radioactive substances. However, the potential cost savings from reduced tubing and casing extraction are not factored into the cement balance plug in 3 annulus technique's estimated savings.

Abstract Well construction in deep high-pressure, high-temperature (HPHT) carbonate wells typically impose the most restrictive restraints and essential requirements for drilling fluid and cementing design and application. This type of well presents specific challenges and difficult technical concerns that must be addressed not only in the drilling phase of the well but also on the long term well integrity. Drilling exploration or an appraisal well accentuates these challenges as formation details may not be fully understood. A recent appraisal well located in offshore Malaysia, presents many challenges especially on the drilling and cementing into its carbonate formation. Among the challenges of completing this HPHT well are high CO2 and H2S exposure, tight equivalent circulating density (ECD) concerns during drilling and cementing, losses from weak interbedded sands and severe losses concerns across its carbonate sections (Karst formation). In the HPHT section of this well, HPHT non-aqueous fluid (NAF) system was designed to meet the criteria for drilling and well test. Also, specially designed self-healing, high temperature flexible and expandable cement was engineered due to concerns of formation subsidence. This set cement design provides flexible properties to cater stress induced by formation movements, coupled with self-healing properties ensuring long term well integrity with its self-repair capabilities. A comprehensive and collaborative approach between drilling fluid and cementing design was among the pivotal factor ensuring the successful well construction of this appraisal well. This paper presents the complete engineering process from coherent well construction planning, drilling fluids and cement slurries design, rigorous laboratory validation, drilling and cementing hydraulic modeling, preventive and collective loss circulation control to successful well drilling execution. It also summarizes the lessons learnt from the operation and recommendations to drill and construct future wells under HPHT environment in this field.

Abstract The lack of sufficient enrollment in vocational drilling training programs has led to a shortage of skilled workers, resulting in difficulties in recruiting and retaining national crews for drilling rigs. Utilizing state-of-the-art simulation technology will enhance the rig crew and trainees’ productivity, educational progress, motivation, and accomplishments. A basic qualitative study investigated the impact of simulation technologies on trainees’ learning, motivation, and viewpoints regarding their education at the vocational training facility for oil-field drilling rigs. The conceptual framework for user reception of information systems was based on Davis's technology acceptance model. Ten drilling crew trainees were selected for semistructured virtual interviews. Subsequently, the data was transcribed, and a manual process of descriptive coding was employed to discover five themes that directly addressed the research topics. Five distinct patterns were identified via the process of analyzing the data. The initial three themes encompassed the simplicity and practicality of teaching drilling application skills through simulator technology. The next two themes were the manner in which the use of the drilling simulator motivated and instilled a sense of enthusiasm in the trainees, hence fostering their inclination to conclude their studies successfully. The study's results demonstrated that using drilling simulators in training proved highly advantageous. It facilitated the establishment of a practical training setting that was secure, economically efficient, and user-friendly. The training familiarized the trainees with the operation and handling of various rig equipment and tools. It enhanced the trainee's drilling and well control skills, increasing their working experience. Additionally, it facilitated the trainees’ experience of challenging scenarios related to different operations and fostered a sense of teamwork. This contributed to a decrease in the rig's non-productive time. The study's findings could provide valuable insights to executives of drilling contractor training facilities regarding the significance of expanding drilling simulation methods to encompass all potential drilling job activities. Drilling simulators can foster beneficial societal transformation among trainees, the drilling rig personnel, and the regional community by enhancing their knowledge and comprehension of drilling procedures.