bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cavings Morphology Analysis: A Critical Geomechanical Tool in Optimizing Drillability
Authors: Das Purkayastha Anjanava , Rana Rohit , Ranjan Kumar Rajeev , Basu Jayanta , Talreja Rahul , Singh Amit 
Published: January 2020

Drill cuttings are a valuable source of information about lithology and wellbore condition. Although an abnormally high number of cuttings would indicate some sort of failure at the wellbore wall, a detailed analysis of cuttings can help to identify the type of rock failure. Cavings, fragments that are relatively larger and of different shape compared to normal cuttings, can be used to decode critical information about the wellbore geometry and formation pressure.
Cuttings analysis is most useful in absence of direct indicators of wellbore condition such as caliper, image logs, or logging-while-drilling (LWD) data, but even in presence of such data, cuttings analysis can be used to corroborate the interpretations with direct measurements. Several mechanisms, such as underbalanced drilling, pre-existing weak planes, stress relief, or even the drilling process itself, can lead to production of cavings. Examining the cavings to interpret wellbore instability and mechanisms responsible for it is an expert's job and requires a good overall understanding of the prevailing geology, geomechanical principles, drilling procedure, and drilling tools.
Identification of wellbore failure during drilling provides a better chance of immediate remedial action, even before a wireline logging program is executed. Differentiating cuttings generated by the drill bit from cavings created by the wellbore failure is not an easy and straightforward task due to a variety of bits and phenomena involved in the generation of cuttings. The first step in this analysis is to broadly define the different types of cavings based on their shape and size. Then, we move to the basic key features of these cuttings, and, finally, provide the remedial action plan for each type.
Drill cuttings analysis was successfully applied to improve hole condition in real time for two wells drilled in the Western Offshore basin, India. One case study illustrates the importance of mud chemistry over the mud weight being used to drill. The second case study underscores the interpretation of shear failure as the reason for cavings from cuttings morphology analysis. In both the cases, timely intervention integrated with the identification of prevailing drilling issues in real time helped in understanding the mud system and its effects on the wellbore.
The novelty of this approach lies in the deep understanding and geomechanical application of cavings in providing timely and cost-effective recommendations to optimize drillability in both the presence and the absence of LWD data. The results can be used during the well-planning stage of future wells and during drilling to improvise mud chemistry or to identify required increase in mud weight to avoid breakouts related to chemical instability or shear failure even though the pore pressure profile may not necessarily require any further increase in the mud weight.
Optimization and Simplification Technology of Maturing Oilfields Gathering and Transportation System and Water Injection System
Authors: Zhao Xinming , Zhou Song , Xu Guoan , Xiang Yong , Li Qing , Zhao Ming , Xia Minmin , Zhu Kaifeng 
Published: January 2020

In the later stage of development of Dagang Oilfield, many problems, such as inadaptable process, severe corrosion of equipment, high energy consumption and high maintenance cost, have been presented in the oilfield surface system. Through the research and field application of the optimization and simplification technology of surface system, the technology series of optimization and simplification with Dagang features has been formed. This article focuses on oil well software metering technology, intelligent control technology of water injection wells, oil well single-pipe transportation technology, gathering and transportation and water injection process optimization technologies.Through the research and application of the optimization and simplification technology of surface system, the metering technology and the single well oil collection technology were simplified, the metering station was cancelled, the mixed water system was shut down, the oil and water pipe network and the process flow were shortened. The production and operation cost, system operation and maintenance expenses and construction investment have been descended evidently. It also has a significant effect on energy saving and consumption reduction and explores a new road for improving the development efficiency and sustainable development of old oil fields.
Carbonate Matrix Acidizing Efficiency from Acidizing Induced Skin Point of View: Case Study in Majnoon Oilfield
Authors: Al-Rekabi Mostafa Abdulkareem , Aktebanee Ahmed , Al-Ghaffari Adham Sabah , Saleem Tahir 
Published: January 2020

The main objective from carbonate matrix acidizing design is to enhance the wormhole network and to avoid any induced damage caused by treatment fluid and pre flush/post flush fluids. Optimization of treatment fluid recipe aims to avoid potential source of damage such as sludge, emulsion and wettability alteration to maintain the new acquired permeability in the acid injection phase. The skin factor trend is modeled during injection and clean up phases to assess matrix acidizing interaction with formation.
This paper will be focusing on real-time skin trend monitoring model which takes wellhead pressure and flowrate values as a two main parameters for formation response interpretation during both Acid injection and flow back clean up phases. Injection multi-rate drawdown well test model was used to monitor the skin trend for injection phase and used forward multi-rate drawdown test model for clean-up flow back phase in post soaking period. The permeability contrast was considered to monitor the diversion effect.
During post flush phase, the treatment fluid (15% Acid including additives) was squeezed into the formation using post flush #1 (mainly solvent system) followed by post flush # 2(mainly 2% formic acid). The wells left shut-in for prolonged soaking period (24 hours). The results show that Skin trend at the end of flow back phase is more than skin value at the end of injection phase by considerable difference which indicate induced and added skin value. The suspect for the source of this increased skin value could be either prolonged soaking period and/or non-optimum treatment fluid design. During flow back period, excessive fluctuating in BS&W and pH was observed which can imply water block and rock wettability alteration.
The ratio of Productivity index at the end of clean-up to the index at the end of injection phase is defined in this paper as "Stimulation Efficiency" and the difference in the skin value at the end of acid injection and the skin at the end of clean up phase defined as "Acidizing Induced Skin" value. The average of this added Skin value ranges from +3 up to +10 with 30% to 40% average stimulation efficiency which lead to increase in skin value that was lowered during acid injection. Production test after each acidizing job validated the skin value ranges at the end of clean up phase.
This efficiency value combined with BS&W trend and content behavior during clean up phase, will give the stimulation engineer an overview to optimize the acid additives and post flush recipe to mitigate above mentioned damages.
Decision Support System for Optimizing GOSP Operation
Authors: Al-Dossary Badr , AL-Naser Mustafa , Al-Dogail Ala , Gajbhiye Rahul , Al-Qathmi Ahmed , Mahmoud Mohamed 
Published: January 2020

It is very important to consider all the units and operating parameters of the individual units in the gas-oil-separation-plant (GOSP) optimization process. For many processes, optimum parameters for the individual units are difficult to implement in the real operation especially for GOSP in which all the units are connected to each other and establishing the optimum control condition for the individual unit will be difficult to implement.
The objective of this project is to develop a generic integrated framework for maximizing the oil recovery by optimizing the gas-oil-separation-plant (GOSP) parameters. A typical Saudi Aramco GOSP plant has been considered as the candidate for the project. In this project, a model consists of multi-stage separators, and stabilization units along with the stock tank to mimic the oil train. Amongst the various parameters, only the controllable parameters such as pressure, and temperature were considered as optimization parameters to achieve the maximum oil recovery. The GOSP plant model was developed using OmegaLand software.
To evaluate the effect of the various parameters many runs were initiated for generating the data. A model is developed by applying artificial intelligence techniques to the data generated by the simulator. The model served as a tool for optimizing the controllable parameter to achieve the maximum oil recovery which is the ultimate goal of the GOSP plant. The generic integrated framework serves as a guide to set the optimum operating condition for maximizing the oil recovery. The optimized parameters can be adjusted by Operation Decision Support System (ODSS).
Slimline High-Speed ESP Application for High Value, Restricted Diameter Wells
Authors: Zabala Wilson , Lastra Rafael , Demarque Vianney , Xiao Jinjiang , Mutairi Khaled 
Published: January 2020

Electric Submersible Pump (ESP) is the most appropriate artificial lift method for moderate to high production rate wells. However, there are shortcomings in ESP technology for applications in slim casing wells with high rate production potential. These applications include wells in which liners as small as 4 ½′ have been installed inside the original casing for well integrity remediation. Some of these wells can produce high rates, however after the slim liner installation, production in these wells must be curtailed to the maximum production allowed by existing slim ESP technology. In addition to that, performance and reliability of current slim ESP technology is subpar compared with larger diameter ESPs.
This paper discusses the development of a new High-Speed High-Rate Slim ESP system that can be installed in casing applications as slim as 5′ and 4 ½′ and it is able to produce higher rates than standard technology. The discussion includes the considerations for the design, the testing plan and the qualification testing results.
There are many challenges associated with the design of an ESP to produce high rates in small diameters. This paper discusses mechanical and hydraulic considerations and the evaluation of trade-offs between efficiency, rotational speed and production rate, among others. Since this is a new technology with much higher operating speeds than standard ESPs, there are currently no applicable industry test standards. This paper presents the approach taken to develop the testing and qualification plan, as well as the results obtained during the testing phase.
This new ESP technology was demanded to operate under very challenging conditions including tight clearances, harsh environment and high fluid velocities. The testing results showed that the system design met the production requirements while maintaining appropriate levels of performance.
The newly high-speed/high-rate slim ESP incorporates multiple innovative design features developed to increase both performance and reliability of the system. Some of these features include a new Permanent Magnet Motor (PMM) design with an advanced control system, a high-frequency variable speed drive, a shaftless protector design, a new slim ESP sensor with high speed data transmission and ground fault capabilities, as well as a new flow/power crossover system with highly reliable electrical connections.
Advanced Modeling and Sensitivity Analysis for Downhole Wet Gas Compressor Applications.
Authors: Lastra Rafael , Montoya Cesar , Aladawy Ahmed , Malkawi Ameen 
Published: January 2020

Downhole gas compression (DHGC) in gas wells is a relatively new concept in production engineering, but it represents one of the most promising technologies to revive dead wells, to boost gas production and to maximize total gas production recovery. This technology could be analogous to electrical submersible pumps (ESPs) for oil wells, as it increases well production by reducing the back pressure at the wellbore sand face; this is achieved by providing boosting pressure to cover for outflow pressure requirements (i.e. tubing losses and well head backpressure). However, downhole wet gas compression applications are considerably more challenging than those for ESPs. The purpose of this paper is to describe step by step the procedures and workflows to evaluate downhole gas compression applications, from information preparation, to multiphase flow calculations and sensitivity analyses.
The applications of this technology are more complex than conventional pumping methods for oil wells. Calculations are more involved with considerations for gas compressibility, multiple flow regimes, liquid volume fraction at compressor intake, compressor pressure ratio requirements, liquid loading conditions, discharge pressure and discharge temperature, among other effects, which are some of the main factors to be measured for this type of application.
There is no standard methodology in the oil industry for gas well modeling and sensitivity analysis for DHGC applications. Just few publications can be found in the literature with some description of the evaluation process but missing some other relevant aspects of the application. This paper presents a systematic process to evaluate applications of DHGC including well performance modeling and compressor simulations.
A new comprehensive methodology has been used for downhole compression application in this study, using nodal analysis software for well performance modeling in combination with a process system simulator to model compressor performance.
Unconventional Field Well Delivery Optimization: Drilling Precise Sand-Channel Targets
Authors: Almasmoom Salahaldeen , Le Viet , Stonestreet David , Al-Faraj Omar 
Published: January 2020

The surge in the worldwide demand for hydrocarbons has resulted in considerable interest in drilling for unconventional resources. The Drilling Engineering Team has reduced the duration and cost of drilling wells by 80% in drilling days and 73% in well delivery cost while targeting more precise sand-channel targets in the Unconventional Field presented in the paper, during a time period of about 10 years.
Optimizing the casing design (moving from seven casing strings to four casing strings), drilling practices (maximizing drilling parameters), and completion practices (moving towards 4-½-in cemented longstring instead of lower/upper completion), resulted in reducing the number of days and the associated drilling cost. The improvements include:
Modifying hole sizes (slimming wells starting from 34-in section to 22-in section).
Combining sections that were previously isolated (for example, combining the targeted sand-channel reservoir with a long shale interval above it in one section).
Eliminating drilling liners and completion tiebacks (moving towards 4-½-in cemented longstring instead).
Improving the drilling fluids program (moving towards high salinity NaCl polymer drilling fluid system for the shallower sections, and reducing mud weights needed to stabilize the long shale interval from 100+ pcf toward 70-80 pcf by utilizing OBM),
Increasing top-hole rate of penetration by strategically moving all the directional nudging into the 8-½-in/8-⅜-in OBM drilled hole section, and decreasing cost of top hole bottomhole assemblies.
Introducing new technology 8-½-in/8-⅜-in PDC bits that drilled the entire hole section with one bit.
Introducing an updated combined logging program.
Challenges of Pressure Transient Analysis PTA: Uncertainty Assessment and Pitfalls in Well Test Analysis-How Much Confidence Does a PTA Interpretation Has?
Authors: Cobanoglu Mustafa , Shukri Ibrahim 
Published: January 2020

Pressure transient analysis (PTA) is one of the best tools to estimate critical well and reservoir parameters. Some of those are reservoir properties, reservoir size and shape (i.e. permeability, fracture properties, reservoir model, distance to boundaries, etc.), completion efficiency (i.e. skin, fracture performance…etc.), tubing performance (i.e. optimum tubing design and artificial lift requirements) and well (i.e. fracture performance, skin, etc.), and reservoir characterization (i.e. dual porosity, layered reservoir, composite, etc.). Therefore, proper interpretation of PTA is crucial to acquire critical parameters for field development and well optimization. Pressure transient analysis technology has improved over the time. However, real-life examples of pressure data to fit a given idealized model are often nonexistent. In addition, well test interpretation suffers from a variety of uncertainties that combined, to reduce the confidence of the analyses. This paper attempts to summarize the uncertainties associated with well test analysis, shows examples of pitfalls in well test analysis, and provides the methods that proposed to identify the uncertainties.
The first phase of the project, a detailed analysis of several PTA interpretations collected from various oil and gas fields in Petroleum Development Oman (PDO), compiled and analyzed to identify the main areas of uncertainty. In the second phase of project, best practices for well test interpretation methods were developed to achieve a consistent interpretation approach across the company. In the third phase of project, five main sources causing an uncertainty on PTA interpretation were investigated, analyzed and demonstrated with relevant actual examples, as well as demonstrating the pitfalls in well test analysis.
The study proposed and developed a six-step PTA interpretation Work Flow including QA/QC steps and the study identified five main uncertainty areas, developed techniques to evaluate each of these, and presented the pitfalls of each uncertainty. Those key uncertainty areas are:
The uncertainty in reservoir properties
The non-uniqueness of the PTA model responses
The limitation of the data set
The physical error in the pressure / rate data (including non-reservoir effects on pressure gauges response such as gauge drift) and the human effect
The implications of well bore storage effect
This document provides a summary and characterizes the five main sources of PTA uncertainties through actual data from PDO in the Sultanate of Oman. This document will also cover the best practices and workflow that have been developed & proposed in order to achieve a step change in the quality and reliability of the PTA interpretations. The implementations of the workflow are presented for a variety of reservoir types and field examples of its implications on well optimization and field developments will be shared.
Building Technical, Commercial and Soft Skills in Evolving Organizations
Authors: Howes C. Susan , Taylor Robert W. 
Published: January 2020

The combination of unevenly distributed demographics and the recent industry downturn have resulted in an exodus of highly experienced workers from the oil and gas industry as employers constrained costs by reducing headcount. Retirement of highly skilled technical experts has further compounded these critical issues. The remaining workforce is talented, but many organizations are experiencing significant capability gaps that are driven from their workforce being inexperienced, under-trained, and lacking access to qualified mentors.
Addressing capability gaps requires an understanding of what skills are needed. New leaders may not be aware of the full spectrum of technical skills, and which skills are best applied to technical challenges. Many leaders manage cross functional teams where several team members work in different disciplines. Once appropriate skills are identified by job functions necessary to perform the work, companies inventory skills and competency levels in their organizations. Individual development programs are developed utilizing available training and development resources to target the gaps and effectively raise the level of competency within the required timeframe.
A complete program includes:
Competency modeling and assessment
Conventional classroom instruction and exercises
E-learning libraries
Virtual learning options
In-house and virtual mentoring
Business workshops and simulations
Rotational assignments and "On the Job" (OTJ) training
Consulting experts to fill gaps temporarily and allow time for staff development
Subject matter experts to provide peer reviews to ensure quality
Successful implementation of a competency based focused training and mentoring program drives companies to close the identified capability gaps and increase business performance. This presentation draws on several successfully implemented programs to demonstrate the applicability and relevance of the program's key elements leading the organization to an increase in overall workforce skill levels.
These referenced examples describe key elements of a competency management system (CMS) implemented by E&P companies globally. The CMS system includes building competency models, developing employee and supervisor assessments, and creating learning plans for employees in both technical and business support positions. The competency models will reflect models that have been approved by the Society of Petroleum Engineers and the Society of Exploration Geophysicists, adding a global standard to the program.
By using the CMS for assessments, senior management can clearly monitor and determine its current competency levels, measure its progress in eliminating competency gaps, identify the competencies that need further development, and update individual learning plans. The expected outcome changes the dynamics of personnel development from curriculum-based training to competency-based in order to accelerate the skills that are required for the company and their specific applications.
Novel Application of Magnetic Flux Leakage-Based Technology Validating Pipe Elongation in Coiled Tubing Drilling Operation
Authors: Wiranata Kevin , Ridene Arafet , Yusoff Mohd Nur Afendy Md , Hamdi Abdullah , Sa Rodrigo , Chaari Youssef , Arifin Mohammad 
Published: January 2020

Coiled tubing drilling (CTD) uses wireline inside coiled tubing (CT) for real-time downhole measurements and controlled actuation of the bottomhole assembly (BHA). In the CTD case under study, after several hundred thousand running feet, the wireline disconnected from its BHA anchor, resulting in lost communication and nonproductive time. By using the input of a CT integrity monitoring system based on magnetic flux leakage (MFL), it was shown that the CT experienced linear plastic elongation, resulting in the wireline being disconnected from the BHA anchor.
CT pipe is fabricated from metal skelps joined together with bias welds. The pipe integrity monitoring system based on MFL was used from the first run of a CT string until its last run, before retiring the pipe. The system was originally designed to detect defects along CT string, but it can also analyze bias weld profile, which cannot be seen outside the tubing. Lengths of each metal strip were noted by comparing the distance between two bias weld points in the same run. CT elongation was then determined by comparing the length of each strip from initial and subsequent runs.
This paper comprehensively studies CT elongation growth over each run and elaborates on the consequence of this elongation for CT operations using wireline or fiber optic cable (e.g., jeopardizing operations). The outcome from this paper helps to prevent recurrence by recognizing the root cause and modifying the slack management practices especially for this operation, which is sensitive to accurate slack calculation.