bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perforation and Flowback Highlights From the Gorgon Field, Offshore Australia
Authors: Wilson Adam 
Published: October 2017

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 182420, “Perforation and Rig Flowback Highlights for the Gorgon Field Development Wells,” by A.K. Morrison, SPE, and J.P. Beinke, SPE, Chevron Australia, prepared for the 2016 SPE Asia Pacific Oil and Gas Conference and Exhibition, Perth, Australia, 25–27 October. The paper has not been peer reviewed.
The Gorgon liquefied-natural-gas project (Fig. 1) is one of the world’s largest natural gas projects and the biggest single resource development in Australia’s history. In 2014, eight Gorgon wells were perforated successfully, intercepting between three and seven commingled zones and gross intervals of up to 500 m per well. This paper contrasts the detailed perforating and flowback plan with the results of the operation where a number of planned, and some unplanned, contingencies were faced.
Perforation Basis of Design
The main element of the Gorgon- project well design that affected perforating was that reservoir sections would be completed with a cemented 70-in. liner in 8¾-in. open hole, with the top perforation approximately 250 m below the liner top. Each well was to be completed in multiple formation zones, with the average gross perforation interval per well (top to bottom shot measured distance) expected to be more than 400 m and an average net perforation interval (sum of perforated zones) of close to 150 m.
Four perforating alternatives were evaluated with respect to their relative operational and subsurface risks:
Tubing-conveyed perforating (TCP) shoot and drop—guns deployed into the liner on a gun hanger before upper completion is run and then fired and dropped after perforation
TCP shoot and pull—a separate drillpipe-conveyed perforation trip before completion with use of a sized kill pill after perforation to mitigate losses before the upper completion is run
Coiled-tubing conveyed
Wireline conveyed
After analysis, the TCP shoot-and- drop option was eliminated because of the additional time and well-control risk of drilling the required rathole to accommodate dropped guns.
Shoot and pull was not considered a viable option because of a lack of a temperature-rated, post-perforation kill pill.
Coiled tubing was rated feasible but with inherently greater operational risks when performed from a mobile offshore drilling unit.
The process concluded that the wireline-conveyed method was the best solution despite requiring several perforating runs per well. Operational issues associated with this technique were identified, and plans were developed for these to be managed safely.
The gun length per trip was expected to be approximately 30 m, necessitating at least five wireline trips to perforate each well, with each run expected to take between one and two rig shifts.
In the event of failure (e.g., unsuccessful cable development), the selected contingency method for deployment was coiled tubing, which was considered a proven alternative.
Direct Strain Mapping of a Cement Sheath; A New Tool for Understanding and Preventing Cement Failure in Thermal Wells
Authors: Iremonger Simon S. , Cheung Benjamin , Carey Jason 
Published: October 2017

Abstract
The design and application of a new cement integrity validation test apparatus for improving thermal cement integrity will be presented. This novel approach allows direct strain mapping of to-scale cement sheath as it deforms under different wellbore stress scenarios. Not only does this novel technique provide insight into elastic cement deformation but also helps elucidate how cracks form and propagate as the cement sheath deforms. Strain mapping is achieved through Digital Image Correlation (DIC) utilizing dual high speed and resolution camera systems. Reliably capturing crack initiation in the frame of view of the stereo camera system proved to be a significant challenge. After multiple design iterations, the best results were achieved with creating a predefined defect site in the cement sheath. Detailed crack initiation and propagation strain maps were created for thermal cements with and without fiber additives. This testing demonstrated how fibers are able to blunt crack propagation and dissipate energy through a fiber pull out mechanism leading to a more ductile failure. Early results are promising and are consistent with previous tests showing an increase in ultimate failure strength in tensile samples with fiber additives.
Slimhole Steam Injector Wells with Insulated Tubing
Authors: Sachdeva Parveen , Damour Jean-Aurélien , Suryanarayana P. V. , Johannson Darren 
Published: October 2017

Abstract
In this work, a slimhole steam injector well using new generation insulated tubing as the production casing string is proposed. Its mechanical integrity is evaluated using High Temperature Post Yield (HTPY) design approach. The thermal impact of this application and the implications of cementing the insulated tubing on its integrity as a casing are examined. It is shown that using insulated tubing as a casing is feasible and viable.
A well consisting of insulated tubing (3.5″ × 5″) as the production casing and a 7″ surface casing is considered. The insulated tubing is cemented to surface. Steam is injected through the insulated tubing to minimize heat loss to formation during steam injection and avoid aquifer temperature increase. Different steam injection conditions are considered. Thermal analysis of the process is conducted using a multiphase flow thermal simulator capable of handling steam. Loads on both the surface casing and the insulated tubing as production casing are then calculated considering the response of the inner and outer wall of the tubular. A High Temperature, Post Yield design approach as described by Suryanarayana and Krishnamurthy [SPE 178473] is used to examine integrity for appropriate loads. In particular, the low cycle fatigue life of the tubular body and connections is calculated and used as basis for design.
Thermal analysis of the steam injection process shows that the steam is delivered to the formation at the same steam quality as the injected surface steam quality. The surface casing satisfies all applicable loads using Working Stress Design (WSD) approach. The insulated tubing satisfies WSD criteria for all drilling loads. The thermally dominated loads, e.g. steam injection, satisfy the HTPY design criteria. Sensitivity to the top of cement below the surface is also analyzed to investigate the effect of buckling under high temperature. The insulated tubing undergoes elastic buckling in the un-cemented section, resulting in acceptable stresses. The number of cycles to failure calculated here are adequate for a well life of 20 years with 3 shut-ins per year.
Insulated tubing is often used as a tubing string in thermal wells for steam injection. Its use as a casing string has not been considered before. The thermal response when insulated tubing is used as casing is different. It is shown here that the insulated tubing can be used as a casing for in thermal wells with specific care exercised in its design. In particular, the thermal performance should be warranted for typically 20 years at high temperature. This means the insulation material should be selected such that it is unaffected by vacuum deterioration over time.
Understanding Sand Control for Thermal Heavy Oil and Bitumen Production Operations
Authors: Romanova U. , Michel D. , Strom R. , Stepic J. 
Published: October 2017

Abstract
Thermal recovery methods, in particular technology based on steam injection, are used extensively around the world for heavy oil and bitumen production. Because of the unconsolidated nature of the majority of such deposits, sand control is required. Design effectiveness of sand control depends on the reservoir type, production technology and operational practices. The industry is facing many challenges such as low oil prices, tight environmental regulations, the need to lower risks while assuring well integrity and longevity and project economics. All of that requires special technical solutions for thermal well design, including sand control.
The paper provides an overview of sand control for thermal heavy oil and bitumen production operations, factors affecting sand control design for thermal projects, sand control devices and industry trends. Laboratory observations and field data are discussed. The impact of steam on different quality heavy oil and bitumen deposits in relation to sand control is discussed in detail. Efficient sand control design for thermal production operations requires a multidisciplinary approach and is an integral part of the well longevity and project economics. Better understanding of the impact of reservoir quality, thermal formation damage and operational practices on well performance is required to assure success of a thermal project.
Verification of FEA Used in OCTG Connection Evaluations
Authors: Meijer G. , Dall’Acqua D. , Nowinka J. 
Published: October 2017

Abstract
Finite element analysis (FEA) is a powerful tool in OCTG connection design and qualification. Connection designers use FEA to examine impacts of design variables on connection performance. FEA is also used in connection evaluation protocols to select configurations of full-scale test specimens, and in comparative assessments to qualify connection product lines. While FEA has become a common tool, analysis of OCTG connections remains complex, and presents numerous challenges related to modelling assumptions, mathematical approximations and solution accuracy – which can vary depending on the inputs, methods and software. These challenges sometimes lead to variation in the quality of connection analysis results. Given increasing industry use for connection design and qualification, the ability to verify correctness and increase confidence in FEA performed by a third party has become an important goal – but no guidelines for such verification are available.
This paper broadly describes a benchmarking process that can be used to confirm that FEA simulations are performed to a suitable level of rigour for the connection modelling application of interest. The process steps include identifying key results of interest, establishing the governing physics and modelling parameters that could affect those results, determining the required level of benchmarking rigour, devising appropriate cross-checks that can be compared to the analysis results, and conducting those checks to increase confidence in the FEA model.
We reference thermal well casing premium connections as an example of a tubular application where FEA is relied upon heavily to support both connection design and service suitability evaluations. Specifically, the Thermal Well Casing Connection Evaluation Protocol (TWCCEP, published as ISO PAS 12835) employs finite element analysis as a means to select the connection configurations for full-scale testing. Connection analysis is used to determine the worst-case combinations of machining tolerances, pin material strength and make-up torque for galling and sealability evaluations. The modelling requirements for this extreme-service application include a number of nonlinearities, and appropriate benchmarking of the FEA is essential if confidence in the analysis results is to be achieved.
This perspective on FEA benchmarking is a suggestion for a more systematic approach to confirming connection analysis is well-conditioned, with flexibility to accommodate the specifics of the connection application and the need for rigour in FEA results. Use of this process for ISO PAS 12835 evaluations and other connection analyses purposes will increase end-user confidence and facilitate effective use of FEA by the oil-and-gas industry.
Research on Damage Mechanism and Control Measures of Casing and Tubing Corrosion in High-Temperature Fire-Flooding Wells
Authors: Long Hua , Sun Shouguo , Zhang Hongjun , Sun Houli , Wang Lei , Liu Manjun , Yu Xiaocong 
Published: October 2017

Abstract
With the development of Fire Flooding test, serious corrosion occurred in N80-steel based tubing and casing string and caused severe damages. Wellbore integrity is getting worse, which gives rise to the abandonment of a well section or the whole well. This problem has seriously hampered the fire flooding development. In this research, the component analysis is first applied to the injection and production gas samples of fire flooding well groups, to determine the reaction mechanism and the main corrosion factors of wellbore tubing and casing string. Then, corrosion dynamic simulation experiments are carried out by the first domestic self-developed experimental device of fire flooding corrosion simulation. Corrosion rate of various string pipes under fire flooding conditions with different gas component is simulated and measured quantitatively by using the traditional weight loss method and inductance probe method, aiming to determine the dynamic corrosion degree during the process of fire flooding, and meanwhile the evaluation on the new developed chemical corrosion inhibitor is implemented. For new wells, the anticorrosive materials for casing and tubing is selected according to test results, and the optimal design of completion casing is carried out, to ensure the injection and production wellbore integrity and anticorrosive performance in the development process. For corrosion wells, chemical corrosion inhibitor was developed, and the dynamic simulation and evaluation of corrosion resistance was carried out by means of the fire flooding simulated corrosion model experiment device. The experimental results show that the corrosion rate of N80 steel can be reduced to 0.0687mm/a when the concentration of corrosion inhibitor is 500ppm. This corrosion rate can meet the need of field development. Field tests show that the above measures can effectively prevent or delay the casing and tubing corrosion damage, and extend the service life of fire flooding wells. The fire flooding wellbore corrosion dynamic simulation experimental device has completely changed the current situation of qualitative corrosion evaluation on casing and tubing in the field and realized quantitative evaluation on corrosion damage of tubing and casing. The results of quantitative evaluation provide the basis for optimal design, anticorrosive performance and integrity of wellbore.
Studies of Aqueous Hydrogen Sulfide Corrosion in Producing SAGD Wells
Authors: Pehlke T. 
Published: October 2017

Abstract
In this research lab and field corrosion coupon testing was completed to determine corrosion rates on commonly used Steam Assisted Gravity Drainage (SAGD) metals. This was done to evaluate general corrosion rates, and how they vary with well depth, and operating environment. Based on this analysis and evaluating scale composition a dominating corrosion mechanism was also determined.
Lab testing utilized high temperature high pressure autoclaves to allow for field various corrosion rate and characterization measurements to be taken under controlled conditions. Measurements taken include linear polarization resistance, weight loss, and zero resistance annode to determine corrosion rates. Cyclic potentiodynamic polarization and potentiostatic polarization measurements were also obtained to further evaluate a materials effectiveness in preventing pitting corrosion. Materials tested in the lab were 1018 carbon steel, Deloro-40 and Stellite-6 hard facing finishes, TN-55TH, galvanized (GLV) J-55, and K-55.
Field coupon testing consisted of installing corrosion coupons at various elevations in the annulus of a producting SAGD well. Coupon materials tested included L-80, J-55, and a GLV-J55+J-55 creviced couple. Analysis consisted of weight loss corrosion rate determination, visual inspections, and x-ray diffraction analysis to determine scale compositions.
Field coupons showed corrosion rates decreasing from 0.0178mm/y at the bottom of the well to 0.0145mm/y at higher well elevations. This corresponded to a decrease in iron sulfide (FeS) scale content from the well bottom upwards. Based on the scales composition, operating conditions, and fluids present, it is likely that the scales were formed through the well known solid-state reaction between aqueous H2S and the metal. High average corrosion rates of 0.263mm/y were measured in the lab, compared to a low 0.0183mm/y in field studies. This difference is due to the inhibiting effects of oil in the field which inhibits corrosion rates and the longer field test duration.
Low Profile Frequency Reconfigurable PIFA Antenna using Defected Ground Structure
Authors: Minh Pham Trung , Duc Nguyen Trong , Vu Phan Xuan , Chuyen Nguyen Thanh , Yem Vu Van 
Published: October 2017

In this paper, we design and implement a low profile frequency reconfigurable Planar Inverted-F Antenna (PIFA) for WLAN, m-WiMAX and UMTS applications. Dierent from several conventional designs, the air layer in our antenna is removed, while the radiator patches and ground plane are printed on two sides of the same substrate. This makes the antenna structure thin and lightweight. The defected ground structure (DGS) and coplanar sorting-trips are also designed for adjusting lower operating frequencies without increasing the antenna’s size. Three PIN-diodes are used in appropriate positions for accurate switches between frequency bands. Moreover, the three radiator patches’ parameters are optimally selected on all configurations using Genetic Algorithm (GA). Simulation results show that depending on the ON/OFF states of the PIN-diodes, the antenna can operate in three applicable frequency bands, i.e., 2.1 GHz, 2.4 GHz, and 3.5 GHz with the corresponding peak gains of 0.48 dBi, 3.55 dBi, and 4.33 dBi. The antenna occupies an overall size of 63.5x33.5x1.6 mm3, which can be easily fabricated and integrated into small wireless devices. Simulated and measured results are also compared to validate the correctness the antenna design.
Motivasi Berprestasi Siswa Ditinjau dari Fasilitasi Sosial dan Ketakutan akan Kegagalan
Authors: Fakhria Milcha , Setiowati Erni Agustina 
Published: October 2017

<p class="IABSTRAK"><strong>Abstract:</strong> The aim of this research is to determine the relationship between social facilitation and fear of failure with achievement motivation. The hypothesis proposed by researchers is that there is a correlation between social facilitation and fear of failure with achievement motivation. The samples included in this research are 200 high school students of tenth graders from SMAN 2 Semarang, MAN 1 Semarang, and SMA Gita Bahari. The measuring tool used consists of three scales, namely the scale of achievement motivation, social facilitation scale, fear of failure scale. Data analyzed used multiple regression and partial correlation. The results showed that there was a significant correlation between social facilitation and fear of failure with achievement motivation, R = 0,528 and F = 38,028 at p = 0,000 (p&lt;0,01). The results of partial correlation test indicate that social facilitation was positively linked to achievement motivation while the fear of failure was negatively linked to achievement motivation.</p><p class="IKEYWORDS"><strong>Abstrak:</strong> Tujuan dari penelitian ini adalah untuk mengetahui hubungan antara fasilitasi sosial dan ketakutan kegagalan dengan motivasi berprestasi. Hipotesis yang diajukan oleh peneliti adalah adanya korelasi antara fasilitasi sosial dan ketakutan akan kegagalan berprestasi. Sampel yang termasuk dalam penelitian ini adalah 200 siswa SMA kelas sepuluh dari SMAN 2 Semarang, MAN 1 Semarang, dan SMA Gita Bahari. Alat ukur yang digunakan terdiri dari tiga skala, yaitu skala motivasi berprestasi, skala fasilitasi sosial, skala ketakutan. Data yang dianalisis menggunakan regresi berganda dan korelasi parsial. Hasil penelitian menunjukkan bahwa ada hubungan yang signifikan antara fasilitasi sosial dan ketakutan kegagalan dengan motivasi berprestasi, R = 0,528 dan F = 38,028 pada p = 0,000 (p &lt;0,01). Hasil uji korelasi parsial menunjukkan bahwa fasilitasi sosial dikaitkan secara positif dengan motivasi berprestasi sedangkan ketakutan akan kegagalan dikaitkan secara negatif dengan motivasi berprestasi.</p><p> </p>
Physical Exercise As Stabilizer For Alzheimer'S Disease Cognitive Decline: Current Status
Authors: Machado Sergio , Filho Alberto Souza de Sá , Wilbert Matheus , Barbieri Gabriela , Almeida Victor , Gurgel Alexandre , Rosa Charles V. , Lins Victor , Paixão Alexandre , Santana Kamila , Ramos Gabriel , Neto Geraldo Maranhão , Paes Flávia , Rocha Nuno , Murillo-Rodriguez Eric 
Published: October 2017

Introduction:
Mental health decline is one of the main responsible factors for augments in health care costs, and diagnosis of Alzheimer’s disease (AD). Some studies stated physical exercise is useful for reduction in cognitive decline and AD. Moreover, a recent review argued that evidence are scarce due to few studies published and lack of configuration information of exercise protocol, such as intensity and duration of exercise, number of sessions and other relevant data, to allow appropriate assessment.

Materials and Methods:
Here, we discussed the possible confounders or factors responsible for these differences and possible neurophysiological mechanisms.

Results:
Most studies revealed a possible positive association between physical exercise and cognitive assessments. There are inconsistencies in studies design responsible for varying use of cognitive assessments and different assessments of fitness. However, these studies do not fail to provide evidence about the benefits of exercise, but fail to make it possible because of the lack of dose-response information in AD patients. Physical exercise of moderate intensity should be considered as standard recommendation to reduce cognitive decline, probably due to the improvement in neurodegenerative mechanisms, and the increase in neuroplastic and neuroprotective neurotrophic factors.

Conclusion:
Therefore, it is suggested that physical exercise is an important neuroprotective modulator, bringing significant control of the disease and amplifying brain functions.