bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Electric Line Tractor Technology Developments Deliver Significantly Increased Job Efficiency, Increased Payload Capability, and Improved Mission Certainty
Authors: Murchie Stuart , McInally Gerald , Tinnen Bård , Worsman Robert 
Published: March 2020

Abstract
Until recently, electric line tractor driving speeds have been lying significantly below their true potential, because of elements related to design, working principles and system dynamics. Several case histories from recent electric line tractor conveyance operations illustrate the number of operational benefits that have resulted from an engineering re-design, through applying the latest electronic and hydraulic technologies to electric tractor conveyance.
Electrohydraulic tractors were developed in the mid 1990s as an alternative means to convey electric line deployed tools along the highly deviated or horizontal sections of wells. The application of this tractor technology has grown considerably over the years, having been applied to convey an increasing range of technology payloads (for example, logging tools, ballistic devices and powered mechanical applications) to an expanding stock of deviated wells with increasing length and tortuosity. The performance and capability of electric line tractor tools has always been a trade-off between numerous limiting factors including the electric line cable (strength, weight, length, voltage and current rating), the surface power supply, the tractor components (downhole motor power and drive train efficiency), and the completion size into which it is deployed. This has until now necessitated tractor pre-set requirements to successfully perform a job, resulting in limitations on performance criteria such as tractor pull force and speed.
This paper discusses recent improvements to the tractor platform achieved through redesign and by applying new electronic and hydraulic developments which enable in-well, on-the-fly optimisation of the tractor components and parameters. The field operations demonstrate the transformation in tractor conveyance speeds achieved, in the order of three and a half times that previously delivered, representing a new standard in electric line tractor conveyance efficiency. These speeds, coupled with increased payload conveyance capability and the improved mission certainty which can be achieved, are even more relevant in wells of significant measured depth, lateral length and challenging well profiles and trajectory complexity.
The technology presented will also allow well completion engineers to plan complex well intervention jobs in demanding wells with more confidence now that it is available to increase operational success.
Significant Time Reduction and Cost Savings Realized Through the Use of Wireline Deployed Milling Services, to Enlarge a Tubing Hanger
Authors: Mangione Alessandro , Gravante Elpidio , Sinibaldi Giuliano , Cianci Adriano , Sala Gianluigi , Magrì Raimondo , Altarelli Crescenzo , Paoli Cristiano , Hallaire Maximilien , Hernandez Andres , Perry Gregory , MacPherson William 
Published: March 2020

Abstract
A producing well located offshore Congo was equipped with a TRSCSSV which failed to open. A velocity valve, with a stem beneath, had been installed to keep the flapper open. This condition, apart from restricting the production, was a temporary solution as defined in Eni's (the operator) well integrity policy; for this reason, the SSV had to be replaced. In order to do so, the completion needed to be removed, which implied cutting the cut-to-release packer. A lock open tool needed to be run in the SSV to allow the cutter to reach the packer. The lock open tool was too big to pass the tubing hanger. Eni issued a challenge to the service industry, to come up with a solution to enlarge the hardened tubing hanger while preserving its mechanical integrity. The solution also had to be deployable quickly as the drilling unit could incur costly standby.
The retained solution used a wireline deployed milling toolstring equipped with a diamond coated bit. The benefits of this solution impacted several areas: the surface read out system allowed for fine control of the milling operation, the combinability of the tools allowed for adequate planning of potential fish recovery while retaining well barriers on a live well and the size of the equipment allowed for a rapid overseas mobilization.
The milling operation was completed in a single run, with a total milling time of 1hr 47min.
The paper will discuss the project scope of work, equipment preparation and job execution, an estimate of the risk and cost reduction delivered, and an estimate of the added production enabled by removing the failed SSV.
Coiled-Tubing Hybrid Open-Architecture System Enables Real-Time Downhole 360-View Camera and Production Logging Test for Increased Performance in a Challenging Gas Field
Authors: Vera Vanessa , Torres Carlos , Delgado Eduardo , Foianini Ivo , Arcanjo Diego , Higuera Josue , Torres Monica 
Published: March 2020

Abstract
Efficiency and effectiveness are strong influencing factors when developing rigless interventions within the current market. In the demanding industry of exploration and production (E&P), a synergy was created from strong collaborations between operator and service companies searching for solutions to provide more diagnostic capabilities, reduce overall cost of operations, and maximize well performance. The solution was found in real-time hybrid coiled tubing (CT) services, which drastically increased reliability and reduced assets and wasted time on location.
Two onshore CT well interventions in the eastern foothills of Colombia where challenging conditions (i.e., high gas-production rate, high tortuosity, and dogleg severity) were overcome using a real-time hybrid CT system are discussed. To optimize the operational time to run a production logging test (PLT) and obtain downhole visual conditions, it was necessary to, in a single run, combine a flow-through, multisided, high-resolution visualization camera (first in industry) with real-time wireline services and a hybrid bottomhole assembly (BHA).
The real-time hybrid integrated system includes a cable to connect any wireline tool and multiple fibers for communicating with additional sensors (i.e., tension and compression) to avoid exceeding the wireline tools’ capabilities, casing collar locator (CCL), and/or gamma ray (GR) sensor. These then correlate as a backup of the logging tool while performing operations as a PLT or injection logging test (ILT) and smarter tools (i.e., downhole multisided camera) that evaluate the perforations and fractures within the desired zones. This occurs in a single CT rig up without the need to modify the hybrid BHA, CT string, or CT connector and reduces the shut-in period of the well because CT and BHA capabilities provide more downhole insight.
The hybrid flow-through sensor and camera BHA communication use the fibers installed in the CT; wireline uses the electric path for its telemetry. Because tool communication is independent, data can be evaluated simultaneously without constraints during the same run and pass, helping reduce additional operations because everything is transmitted from downhole, recorded, and displayed at surface the same time the tool senses or sees it.
In an industry that demands continuous improvement during each stage of a well, increasing efficiency, reducing operational time, and developing technologies and techniques without compromising safety is no longer a request—it is now mandatory. This technology provides the benefits of fiber-optic and electric cable together and near limitless freedom to deploy multiple technologies independently or simultaneously without interference—a solution only an open architecture system can provide, establishing a step forward within the industry.
Powerful Hydraulic Coil Tubing Tractor Facilitates Stimulation Application in Extended Reach Wells Thru Completion Operations
Authors: Alsaiood Hussain , Otaibi Abdulrahman , Duthie Laurie , Aybar Umut , French Andrew 
Published: March 2020

Abstract
Matrix acid stimulation in carbonate formations can often be vital to remove formation damage post drilling and achieve a more uniform production profile. Reaching well total depth (TD) is critical for an effective treatment in extended reach wells (ERWs) completed with an electrical submersible pump (ESP). The ESP completion with minimum restriction of 2.44-in. limits the coil tubing (CT) and downhole tools size. Hydraulically powered CT tractors are an ideal solution to pull the CT to TD (Saiood et al. 2018).
The completion minimum restriction only allows for 2-in. CT with 2-1/8-in. OD hydraulically powered CT tractors and a maximum pulling force of 3,200 lbs. Pre-job CT design-aided simulations predicted the 2-in. CT size and a 2-1/8-in. CT tractor would not reach well TD due to unfavorable trajectory and therefore potentially jeopardizing a successful stimulation treatment. An alternative method is to utilize 2-7/8-in. CT combined with a 3.5-in. hydraulically powered tractor to conduct matrix acid stimulation prior to installing the upper ESP completion with restricted ID.
This alternative arrangement allows for a maximum pulling force of 9,200 lbs, ensuring a greater reach in ERWs and effective treatment. It also tolerates higher pumping rates with 2.875in. CT (up to 5 bbl/min as compared with 2 bbl/min for 2-in. CT), reducing the exposure time of acid on surface, reaching optimum rates faster creating favorable wormholes in the carbonate formation and reducing the pumping operation time by up to 50%. Matrix acid stimulation is then completed with the drilling rig still in position post drilling operations. Thereafter, the upper ESP completion with restricted ID is installed.
This engineered solution provides an alternative for CT interventions in extended-reach horizontal wells featuring completion restrictions, where the main challenge is to maximize the reach for optimum stimulation. The approach of combining the 3.5-in. hydraulically powered tractor with 2.875-in. CT pipe successfully enabled effective stimulation of the openhole section to a 27,000-ft. TD in a challenging downhole environment.
Analysis and Case Study: Comparing CT Slim Tractor Performance Using Different CT Sizes in 3 Wells
Authors: Saeed A. , French A. , Moore N. B. 
Published: March 2020

Abstract
For coiled tubing stimulations each CT size offers various advantages and limitations, including but not limited to; maximum pump rate, logistics, fatigue life and cost. In extended reach (ERD) wells CT Tractors can be utilized to improve coiled tubing (CT) access of the horizontal section of the well-bore. The objective of this study was to compare the performance of a slim CT tractor with various sizes of CT, namely 2" and 2-3/8".
Tubing Force Analyses (TFA) were performed for a group of wells using CT modeling software with friction coefficients back modeled from previous CT interventions in the same field. Three similar candidate wells were chosen where CT was predicted to lockup prior to reaching Total Depth (TD) without the use of a tractor, and where TD was able to be reached with the use of a tractor for both 2" and 2-3/8" CT. During field operations down-hole pressure sensors and tension compression sub were included in the BHA to verify the effectiveness of the CT tractor with live readings.
The field operations demonstrated that 2-3/8" CT reached further in the wellbore prior to activating the tractor. The operations confirmed that the slim hydraulic CT Tractor was able to pull both 2" and 2-3/8" CT a significant distance past CT lockup depth. Matrix stimulations were successfully performed on each of the 3 wells. The study concludes that both 2" and 2-3/8" CT combined with a hydraulic slim tractor were both appropriate solutions to access extended reach open hole for Matrix stimulation operations.
Production engineers have case study results to show the effectiveness of using 2" vs 2-3/8" CT with a slim hydraulic tractor to access ERD wells for stimulation operations.
Worldwide First Successful Production Logging of Tri-Lateral High Temperature Coiled Tubing Drilled Sour Gas Well, Performed in a Single Run Using Innovative Reentrance System Without Whipstock Guides
Authors: Saeed Abubaker , Hamid Saad , Yakovlev Timofey , Sagr Hani , Harthi Sultan 
Published: March 2020

Abstract
The job results from an operation using a wireline-operated lateral access tool (LAT) with a production logging tool (PLT) on E-coil are presented. The objective was to successfully identify, enter and acquire production data in each of the openhole laterals as well as the main borehole in order to quantify production and identify any cross-flow.
This operation is enabled by the use of a wireline-operated LAT. The tool can identify where the lateral window is located in the well and provide orientation data. With the LAT, the bottom sub can be indexed to enable entry into the lateral, while sensors package would provide positive confirmation and identification of a particular, targeted lateral. The system is compatible with a number of mono-cable logging tools and can be deployed using both E-line as well as Coiled Tubing. This paper describes the operation in detail and discusses the output and evaluates the results, which demonstrate the efficiency and accuracy of finding and entering the laterals.
The operation was conducted on a well in Saudi Arabia which was drilled using underbalanced coiled tubing drilling (UBCTD) technique in 2013 and included three, slim openhole laterals. In early 2014, the well was put on production with unknown contribution from each of the lateral sections, but interlateral cross-flow was suspected, leading to the need for intervention. A number of approaches were considered with special consideration given to a new technology that had been developed locally and run with success on some other oil and water wells in the region. This technology had not been utilized previously in slim openhole wells with predominantly gas production. Challenges were anticipated regarding how some of the sensors would perform over two critical areas: identification of the lateral windows and confirmation that the lateral had in fact been entered successfully. The results of this operation demonstrate that the sensors can operate successfully in this environment. The operator was able to acquire critical reservoir information about each of the openhole laterals as well as the main bore, enabling further understanding of well production and reservoir depletion efficiency.
This case study demonstrates the innovative application of LAT to enable the production logging (PLT) and evaluation of slim openhole laterals in a gas well drilled with UBCTD compared to previous cases which were predominantly oil producers and water injectors.
Validity and Reliability of a Hausa Language Questionnaire Assessing Information, Motivation and Behavioural Skills for Malaria Prevention during Pregnancy
Authors: BALAMI AHMED DAHIRU , Said Salmiah Muhammad , Zulkefli Nor Afiah Muhammad , Norsa’adah Bachok , Audu Bala Muhammad 
Published: March 2020

Abstract
Background: Many studies on malaria knowledge, attitude and practice among pregnant women have been conducted in Hausa speaking communities in Nigeria. Despite this, no standard and uniform instrument for assessing this important public health problem has been developed in the Hausa language, even though it is widely spoken. The aim of this study was to develop and validate a questionnaire in Hausa language assessing information, motivation, and behavioural skills for malaria prevention during pregnancy.Methods: The questionnaire was first developed in English language, and then assessed for its contents by a team of experts. It was then forwardly translated to Hausa, and backwardly translated again to English by independent language experts. These two English versions were then compared by a Public Health expert, following which the questionnaire was administered to 190 Hausa speaking antenatal care attendees. Exploratory factor analysis was performed on the data collected. Sixty three out of the 190 respondents were invited after two weeks to answer the same questionnaire, following which reliability tests were performed.Results: The questionnaire showed good internal consistency, with Cronbach’s alpha values of 0.859, 0.890 and 0.773 for information, motivation and behavioural skills constructs respectively. The motivation and behavioural skills constructs were able to delineate their items into three and two sub-sections respectively. The factor loadings for the two constructs ranged from 0.610 to 0.965. As for test retest reliability, the Krippendorff’s alpha values for the items of the motivation section ranged from 0.941 to 0.996; that for behavioural skills ranged from 0.810 to 0.953, while for frequency of ITN use, it was 0.988. The Cohen’s kappa values for the information section ranged from 0.689-0.974, except the item for ‘fever’ (zazzabi) which was 0.382, and was as such reworded to a simpler terminology ‘hotness of the body’ (zafin jiki).Conclusions: The Hausa language IMB questionnaire on malaria in pregnancy demonstrated good validity, and a high level of reliability. It is as such recommended for use among Hausa speaking communities to ensure uniformity and objectivity.
Effect of internal limiting membrane peeling on normal retinal function evaluated by microperimetry-3
Authors: Qi Yue , Wang Zengyi , Li Shi-Ming , You Qisheng , Liang Xida , Yu Yanping , Liu Wu 
Published: March 2020

Abstract
Introduction To evaluate the effect of internal limiting membrane (ILM) peeling surrounding macular holes (MH) for the function of retina by microperimetry-3(MP-3). Materials and Methods This is a prospective, cohort study which included patients with MHs who were treated by 23-gauge 3-port pars plana vitrectomy and ILM peeling with air tamponade. Color fundus photography, retinal optical coherence tomography and MP-3 were performed 1 week before, 1 and 4 months after the operation. In MP-3 examination, a customized follow-up pattern with 45 spots in the central 8° visual field was used. The spots corresponding to the retina surrounding macular holes were selected for comparison of pre- and post-operative function. Results We included 44 eyes of 44 patients with best corrected visual acuity (BCVA) of 1.06±0.40 (logMAR). All eyes achieved an anatomical success at 4 months. BCVA significantly improved at 1 month (0.53±0.30, P<0.01) and 4 months (0.31±0.24, P<0.01), respectively. Mean retinal sensitivity (MRS, dB) of the retina surrounding macular hole was 23.46±3.01 dB at baseline, and significantly increased at 1 month (26.25±2.31 dB, u=-4.88, P<0.01) and 4 months(27.14±2.45 dB, t=-6.29, P<0.01). Patients with increased MRS are significantly younger than those with deceased MRS (59.72±3.22 years vs. 65.60±8.19 years, P<0.01). After ILM peeling, the increasing extent of MRS was significantly higher in inferior and nasal retina than in superior and temporal retina at 1 and 4 months (P<0.05). Conclusion ILM peeling in normal retina will not decrease the retinal function in a short-term after surgery.
Monitoring intrapartum fetal heart rates by mothers in labour in two public hospitals: an initiative to improve maternal and neonatal healthcare in Liberia
Authors: Borzie Korpo , Jasper Noah , Southall David , MacDonald Rhona , Kola Adeyemo Abass , Dolo Obed , Magnus Asinya , Watson Diane , Casement Maire , Dahn Bernice , Jallah Wilhelmina 
Published: March 2020

Abstract
Abstract Background: In low-resource settings with few health workers, Fetal Heart Rate (FHR) monitoring in labour can be inconsistent and unreliable. An initiative to improve fetal monitoring was implemented in two public hospitals in rural Liberia; the country with the second lowest number of midwives and nurses in the world (1.007 per 10,000 of the population). The initiative assessed the feasibility of educating women in labour to monitor their own FHR and alert a midwife of changes detected.Methods and Interventions: 474 women admitted in labour without obstetric complications were approached. 461 consented to participate (97%) and 13 declined. Those consenting were trained to monitor their FHR using a sonicaid for approximately one minute immediately following the end of every uterine contraction and to inform a midwife of changes. If changes were confirmed, standard clinical interventions for fetal distress (lateral tilt, intravenous fluids and oxygen) were undertaken and, when appropriate, accelerated delivery by vacuum or Caesarean section. Participants provided views on their experiences; subsequently categorized into themes. Neonatal outcomes regarding survival, need for resuscitation, presence of birth asphyxia, and treatment were recorded.Results: 461 out of 474 women gave consent, of whom 425 (92%) completed the monitoring themselves. 387 of 400 women who gave comments, reported positive and 13 negative experiences. 28 participants reported FHR changes, confirmed in 26 cases with meconium stained liquor in 17. Fetal death was identified on admission during training in one mother. 13 neonates required resuscitation, with 12 admitted to the neonatal unit. One developed temporary seizures suggesting birth asphyxia. All 26 neonates were discharged home apparently well. In 2 mothers, previously unrecognized obstetric complications (cord prolapse and Bandl’s ring with obstructed labour) accompanied FHR changes. Resuscitation was needed in 8 neonates without identified FHR changes including one of birth weight 1.3 Kg who could not be resuscitated. There were no intrapartum stillbirths in participants. Conclusions: Women in labour were able to monitor and detect changes in their FHR. Most found the experience beneficial. The absence of intrapartum stillbirths after admission and the low rate of poor neonatal outcomes are promising and warrant further investigation.