bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chamber Gas Lift in Horizontals
Authors: Hardegree C. N. , Gerrard B. A. , Wildman S. L. , McKenzie K. S. 
Published: October 2018

Abstract
This paper highlights a pilot project in which chamber gas lift was installed in two unconventional horizontal wells. Chamber gas lift, as a combination of deep gas lift and intermittent gas lift, allows for an efficient, closed completion with cyclic injection of high-pressure gas, which expands and rapidly displaces fluid at high velocity from deep in the well. Development of the system was a collaboration internally and in conjunction with the vendor to install what was historically a vertical well assembly through the curve section and into a horizontal wellbore. The chamber assembly was successfully designed, sourced, manufactured, installed, and operated. To modify the design from vertical to horizontal applications, components were custom-designed to maintain a sealed chamber. Components deemed most likely to fail are replaceable by slickline intervention. Results indicate a sustained lower downhole pressure than the previous intermittent gas lift system, an increase in production, and good chamber-sweep efficiency.
Energy Management Applied to Electric Submersible Pumping ESP
Authors: Martinez E.. , Caicedo A.. , Paredes L.. , Guevara M.. , Álvarez E.. 
Published: October 2018

Abstract
The continuous evaluation of electric submersible pumps (ESP) performance and its integration within the energy management system in the operation of Blocks 16 & 67 of Ecuador allowed to develop a specific procedure to assess the efficiency of ESPs in order to identify energy improvement opportunities.
This procedure is summarized with the Significance Matrix, a tool that integrates ESP's field data such as production history and electrical measurements to estimate hydraulic and electrical power requirements, and a specific method for efficiency evaluation.
The result of the Significance Matrix is the categorization of each ESP system as significant or no-significant use of energy. The significant uses of energy are further analyzed to design an action plan that is prioritized through technical and economic assessment.
The comparison between the Significance Matrix of December 2014 and November 2017 showed that the optimization of eight (8) ESP systems resulted in an average reduction of 49 BDPD in fuel consumption that can be translated to a decrease in greenhouse gases emission of 20 tCO2 per day. Moreover, the increase in average efficiency of the ESP systems from 25.4% to 40.9% projected a reduction of 0.99 MW-day of energy consumption for artificial lift.
This analysis also led to identify wells that were not profitable at the actual operating conditions. A total of 10 wells were closed in the same time period to be replaced with production of more efficient and cost-effective wells.
This approach of energy management was developed considering the methodology of the ISO 50001 standard. The conclusion of the study demonstrated that well intervention to improve energy efficiency of ESP systems led to achieve net cost savings and greenhouse gases emissions reduction.
Material Overview for Electric Submersible Pumps: Part I – Metallic and Ceramic Materials
Authors: Xiao J J , Lastra Rafael , Roth Brian , Lee Woon 
Published: October 2018

AbstractElectric Submersible Pump (ESP) is a key artificial lift technology to the petroleum industry. Worldwide installations of ESPs are in the range of 130,000 units, contributing to about 60% of the total worldwide oil production. An ESP is made up of hundreds of components integrated together to perform the lifting function. Materials in these components belong to several categories including metals, ceramics, polymers, and others. A good understanding of these materials and vigilant selection for a specific application are critical to the reliability and run life of an ESP system. This paper presents an overview of two classes of materials used in ESP systems: metallic and ceramic materials. A subsequent paper is planned to cover all other categories of materials. The intent is to provide a reference for ESP field application engineers who are responsible for ESP design, component selection, equipment longevity and production optimization.The information compiled in this paper is a result of extensive literature review. It covers materials used in the motor, protector, pump, and cable (Sensor, packer, Y-tool, diverter valve, surface components of variable speed drives and transformer not included). For each class of materials, it identifies relevant material properties and discusses suitable application conditions.
Efficiency Study in Vizcacheras Field and Implementation of PMM Motors to Increase Production Capability
Authors: Tiofiolo A. L. , Dotta J. J. , Teves R.. 
Published: October 2018

Abstract
Vizcacheras is a mature oil field with the highest electric energy consumption among YPF fields. This consumption and the limitations in electrical infrastructure have constrained the growth on the number of ESP lifted wells and consequently the increase of production from the field. Permament magnent motor (PMM) technology was indentified as alternative to reduce power consumption in ESP operated wells in Vizcacheras field. This paper summarizes the field trial of PMM in Vizcacheras field.
The methodology of evaluation includes the power losses calculation of each component of ESP system and the use of hydraulic power as means to make a fair comparison between asynchronous motors (ASM) and PMM. The results of the test shows a total power saving about 17% with a significant reduction of current across ESP power cable and lower motor operating temperature.
Gross estimation about the impact of PMM technology on field and country bases are carried out to show the potential value of this technology in order to increase production by making available energy for other projects and making economically viable those wells with marginal production.
Successful Application of an Innovative Geometry of Progressing Cavity Pump in Application with High Sand and Gas Content. Colombian Successful Case in La Cira Infantas
Authors: Labrador Laura , de Sales Paola , Valderrama Luisa , Molina Jesus , Ferrer Jose 
Published: October 2018

Abstract
Located in the Middle Magdalena River Valley basin, in the department of Santander, municipality of Barrancabermeja in the rural area of El Centro. La Cira-Infantas is the oldest Field in Colombia and with it, the oil industry was born in Colombia. It has proven reserves of 172 MMBOPD, it reached a production of 65000 barrels in 1939 until it declined to 5000 BOPD in 2005. Through an association contract between two operators, looking for the implementation of new technology, in 2017 45000 BOPD were obtained.
During its operation and through the implementation of the secondary recovery method in the field, a high gas and sand content was identified as a problem for high fluid production wells. This has generated premature flailures in the artificial lifting system with Progressing Cavity Pumps during the production of the Arenas C interest zone that raises the costs to the point that makes them economically nonviable. According to the needs of the field and looking for new and better solutions, the design and application of a pump with a special geometry that allowed giving viability to the operation of these problem wells, was performed, thus expanding their run life and reducing costs associated to their intervention. The implementation of this type of pump has allowed a 63% reduction in installation, maintenance and operation costs, and 86% in differed and production loss costs; in general, a 67% economic benefit versus the conventional system was obtained providing technical and economic viability to the development of these reserves.
Innovative Well Designs for HGOR: Extending Gas Production with Common Gas Well Deliquification Techniques
Authors: Goldney J. Clifton , Mohando B.. , Cometto G. Perez , Ballarini M.. , Mazzola R.. 
Published: October 2018

Abstract
A novel and flexible completion design for HGOR Wells is presented to cover all the gas well production stages in order to avoid rig interventions during natural flow which would reduce gas production potential due to water influx into the reservoir.
The objective of this paper is to introduce the proposed completion designs so other engineers can apply and improve them in their HGOR wells, maximizing gas production and reducing costs.
After studying the conversions from natural flowing wells to Artificial Lifted wells in which gas production was never recovered, the behavior was determined to be from damage (water blockage) in the near wellbore caused by the fluids used in the rig operations.
A decision was made to anticipate the inherent problems through a flexible completion design that allows for the production of different reservoirs, with tubing and/or annular flow, plunger lift, gas lift, and changing to Sucker Rod Pumping without moving tubing or killing the well, especially in the gas reservoirs.
The flexible completions also allowed for further studies of the well and proposed interventions to assist the flow.
Effective Secondary Recovery Stimulation Using Solid Propellant Technology for Tight Sand Development in Sirikit Oil Field, Thailand
Authors: Toempromraj Wararit , Weeramethachai Deephrom , Kiatrabile Thanita , Sangvaree Thakerngchai , Nadoon Apiwat , Sompopsart Suwin , Duncan Robert , Mai-Cao Lan , Havalda Richard , Havalda Paul 
Published: October 2018

Abstract
The Sirikit Field, a mature onshore field operated by PTTEP in northern Thailand, derives production from sandstone reservoirs. While production from many of the shallow pays have been well-developed and optimized, comparatively few of the deeper and tighter sands have been similarly produced. Various methodologies have been trialed to enhance production from these tight sands and an examination of results will be presented in the context of geology, engineering and economics. This field, like most in the world, was produced initially by primary recovery (natural flow and various artificial lift mechanisms). Later in the development phase, secondary recovery (waterflooding) was implemented in the Sirikit Main area with the aim of improving production from the shallower, higher permeability, reservoirs. The deeper, lower permeability, sands have not undergone secondary recovery. It is foreseen that the vast majority of STOIIP can be extracted from these tight sands and will ultimately be the future of Sirikit long term production.
Several secondary recovery methods were evaluated. Waterflooding was ruled out as an option due to poor reservoir properties which were not favorable for flooding displacement as well as a high injection pressure requirement. The focus then became well stimulation as the main strategy to enhance production from these tight reservoirs. Initial well stimulation technology was the use of larger size perforation guns for the low porosity sands in order to improve reservoir penetration and overcome damage zones. Analysis after field trials showed that the deep penetration perforations had insignificant production improvement. Consequently, solid-propellant technology, which is capable of creating near wellbore fractures, was field trialed. Two types of solid-propellant were tested: "regressive" burning propellant and "progressive" burning propellant. The "regressive" burning propellant results were inconclusive; however, the "progressive" burning propellant results showed clear improvements in production. Moreover, in order to create deeper fractures, "hydraulic fracturing", which requires higher investment, was tested in parallel to the smaller scale investment perforation guns and solid-propellant; however, the results were no better than the "progressive" burning propellant. Consequently, the "progressive" burning propellant provided the positive results at the best economics.
Different well stimulation technologies may be appropriate for varying geologic, engineering and economic conditions. For tight or damaged reservoirs, progressively burning propellant may prove to be the most efficient and cost effective technology for secondary recovery.
Integrated Solution to Optimize Drilling Efficiency and Production in Marginal Tight Oil Field Development: A Case from Songliao Basin, North China
Authors: Wang Wei , Zhao Yuwu , Xue Huizhi , Wang Huijun , Chen Jing , Wang Fei , Fu Zairong , Li Cang , Chen Chengqian , Wang Shuai , Yuan Xiangwei 
Published: October 2018

Abstract
Tight oil filed A located in Songliao Basin North China has been producing for over 15 years. During Phase I, most of primary production came from vertical/directional wells with fracturing operation, the average production is 0.3 ton per well at the end of 2012 and only 8.78% oil recovery is recorded. This marginal oilfield stepped in to Phase II with a horizontal drilling campaign to increase final recovery rate.
The length of planned horizontal section more than 1500m for single well within extra thin tight reservoir (around 1.5m TST). Meanwhile, the budget is very limited during down turn. The drilling efficiency is the most crucial element to ensure the success for this project. Servals challenges was identified during pre-drilling assessment:
Dogleg severity(DLS) in this extra thin laminated reservoir is very unstable base on previous drilling practices Ensure smoothly trajectory control within such narrow geosteering window with high rate of penetrate(ROP)
To overcome above challenges, an integrated solution was developed implemented to this drilling campaign:
Fit for purpose rotary steering system (RSS) was tested including the point-the-bit RSS and push-the bit in this project and found the best solution to ensure efficiency DLS finally. A boundary mapper LWD tool with ability to map multiple key boundaries, this method not only support proactive geosteering to keep trajectory within narrow geosteering window and avoid unnecessary adjustment, out of target or sidetrack, but also can help to keep the trajectory within fast ROP zone during real-time operation.
Two typical wells were completed successfully. Outstanding outcomes have been observed by implementing this integrated approach in the complex target reservoirs. The drilling efficiency was improved by 38.7%~132.6% with smoothly trajectory control. The complex structure was identified clearly and the average Net to Gross (NTG) more that 97.5%, and the production reached to 18ton/day which far exceeding expectation.
The successfully application of the integrated solution in extra thin reservoir tight oil field will lead to improve drilling efficiency and save budget, increasing the production and well economics. We believe this approach and technique could address another similar formation development.
Experimental Study of Frictional Pressure Loss for Eccentric Drillpipe in Horizontal Wells
Authors: Khatibi Milad , Wiktorski Ekaterina , Sui Dan , Time Rune Wiggo 
Published: October 2018

Abstract
The downhole friction is a response to mechanical and hydraulic forces. The mechanical friction takes place when the drillpipe is moving in the wellbore, either in translational or rotational mode. The hydraulic friction occurs due to the circulation of fluids flowing downwards in the pipe, and upwards in the annulus. The additional factors that affect the hydraulic friction are drillpipe rotation, surface roughness, wellbore geometry, etc.
This paper experimentally examines hydraulic friction and studies its variations with adjustable operational parameters (flow rate and rotational speed). The experiments were performed using two pipes, where one was located inside the other. The outside pipe with an inner diameter of 0.04 m simulated the wellbore walls, and the inside one simulated the drillpipe with an outer diameter of 0.025 m. The pipes’ inclination was 5° from the horizontal axis. The drillpipe could be rotated by an electric motor with speeds up to 1000 RPM (revolutions per minute). Spherical glass beads were used to simulate the cuttings behaviour in the wellbore. The pressure gradient variations associated with fluid flow, pipe rotation as well as particles movement was measured over the test section (length of 1.52 m), using a pressure transducer. In addition, a high-speed camera, installed outside the outer pipe, was used to take images of the particles distribution and pipe dynamic oscillations.
The combined effect of fluid flow rate, drillpipe rotation and presence of particles on the hydraulic friction between the outer and inner pipes is investigated in this study. The data analysis for the single-phase liquid flow showed that the pressure loss increased with RPM. It was seen that the secondary flow, created by the drillpipe rotation, was not the only reason to affect the pressure loss, but the drillpipe's eccentricity variations with RPM and flow rate also had a considerable effect. A higher drillpipe eccentricity provided lower friction factor, in the case single-phase liquid flow. Finally, empirical relations to describe the drillpipe eccentricity and hydraulic friction factor as functions of RPM and flow rate were proposed. When the particles were present, the friction factor decreased with RPM.
The above-mentioned conclusions and relations are valid for a Newtonian fluid in the turbulent regime.
Drilling Optimisation in Hard and Abrasive Basement Rock Using a Conical Diamond Element Bit
Authors: Abdila Sayid Faisal , Sondang Jaka , Maaruf Pranefo , Mardiana M. R. , Noviasta Bonar , Astasari Kanya , Febriarto Hendriyan 
Published: October 2018

Abstract
Pertamina EP recently executed an exploration drilling project in Sumatera area. The objective was to evaluate the oil reserves contained in the fractured volcanic basement reservoir zone. The very hard (26,000 psi average compressive strength, with spikes of up to 50,000 psi) and abrasive nature brought drilling challenges, in particular, how to effectively and efficiently fail and fracture the rock. In a well in the previous drilling campaign, 10 runs of bit were required to complete the 294-m interval hole section containing basement formation. Various roller cone and PDC bit designs were utilized, with a resulting maximum penetration rate capability of 1.25 m/h and maximum run interval capability of 56.44 m. Another well with a basement interval of 463 m consumed 11 bit runs with maximum run drilling interval and penetration rate of 64 m and 1.56 m/h, respectively.
A conical diamond element (CDE) bit was proposed to achieve more efficient drilling in the basement. The 3D geometry of the conical diamond elements, which are placed across the bit blade, provided both a superior impact and wear resistance and concentrated point loading onto the formation; these characteristics enable the bit to cause failure and fracturing of the hard-to-drill rock more efficiently. A diamond layer in the bit is twice as thick as that of a conventional PDC cutter; this enhances impact strength and improves overall bit durability.
CDE bits were implemented to penetrate the basement formation in two different wells in Sumatera area. The wells were designed as directional J-type wells with maximum inclination of 70°. In the first well, eight-bladed and seven-bladed CDE bits were run with an excellent result of 131-m and 176 m of drilling interval achieved, respectively, yielding up to 211% of drilling meterage capability improvement (compared to the previous well). The rates of penetration (ROP) generated by CDE bits were also large; up to 4.17 m/h ROP was achieved (instantaneous on-bottom ROP reached up to 20 m/h), which was equivalent to 333% improvement. In the second well, the seven-bladed CDE bit generated 230 m of drilling interval with 3.27 m/h ROP, improving the offset well performance by 259% (in terms of interval) and 109% (in terms of ROP). The CDE bit significantly saved operating time and cost by improving the drilling speed and, most importantly, eliminating unnecessary trips to change the bit. The estimated potential savings from CDE bit utilization in these two wells reached more than USD 1.1 million.
The drilling optimization in Sumatera yielded insights into CDE design and features appropriate for basement application, and the engineering study behind the successful execution, actual drilling operation, and run performance comparison provided information for future such operations.
Study to Evaluate the Effect of Using Expansion Materials with Cement Slurry for High-Pressure/High-Temperature Wells
Authors: Shafqat A. U. , Taoutaou S. , Abdurrahman R. , Maksoud A. A. , Otaremwa L. 
Published: October 2018

Abstract
Oil and gas operators are facing more challenges than ever before to sustain production and to effectively minimize workover cost associated with remedial cementing. Previously, achieving the initial hydraulic seal with a good cement bond log was considered the only indicator of complete and durable zonal isolation throughout the lifetime of the well.
However, in a well drilled in a stressful environment, the initial zonal isolation can be jeopardized because of the changes in downhole conditions, primarily temperatures and pressures. Such cyclic changes in downhole pressures and temperatures generate radial cracks in cement and can cause the development of microannulus at casing/cement and cement/formation interfaces.
Extensive studies have been conducted in the past to understand the technical challenges to designing cement slurries with enhanced mechanical properties regulating the flexibility of set cement to withstand the stressful environment at downhole conditions. However, limited work has been done to evaluate the structural changes and impact on the set cement durability due to the requirement of expansion in set cement to eliminate the risk of microannulus.
A new methodology called industrial computed tomography is introduced to investigate the structural changes or cracks in set cement cured with various concentration of expansive additives. The novelty of this new methodology is that it represents a step change in defining the linear expansion requirement for given well conditions without jeopardizing the wellbore integrity.