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In order to satisfy the machining requirements of aero-engine casing in modern aviation industry, this paper investigates three main issues during the design and development process of a five-axis machine tool with high accuracy, stiffness and efficiency, including whole structure design, key components design, and supporting stiffness design. First, an appropriate structure of five-axis machine tool is determined considering the processing characteristics of aero-engine casing. Then, a dual drive swing head and a compact motorized spindle are designed with enough drive capability and stiffness, and related structure, assembly method, cooling technology, and performance simulation are given in detail. Next, a design method of supporting stiffness of guide is proposed through the deformation prediction of the spindle end. Based on above work, a prototype of machine tool is developed, and some experiments are carried out, including performance tests of swing head and motorized spindle, and machining of a simulated workpiece of aero-engine casing. All experimental results show that the machine tool has satisfactory accuracy, stiffness and efficiency, which meets the machining requirements of aero-engine casing. The main work can be used as references for engineers and technicians, which are meaningful in practice.

Slip is one of the most critical components for the frac plug, which would lodge into the casing and lock the frac plug in place during the setting and anchoring process. However, fracture failure of slip significantly affects the hydraulic fracturing effects and has attracted tremendous attention. In this paper, a three-dimensional contact model is applied to explore the setting process of slip. The effects of key structural parameters such as apex angle, inclination angle, and wedge angle on the contact characteristics of slip are systematically investigated. Numerical results indicate that the maximum contact stress appears at the contact area between slip tooth and the casing's inner wall. Besides, the maximum contact stress generally increases with the increase of apex angle and inclination angle, while decrease linearly with the rise in the wedge angle. Experimental results show that the slip teeth get blunt and appear severe plastic deformation, which arises from stress concentration. Comparison of biting area indicates that the experimental results are about 21.3% larger, which still have a reasonable agreement with the numerical results. These obtained results can guide the parametric selection of plug slip and other similar components.

Explosion models based on Finite Element Analysis (FEA) can be used to simulate how a warhead fragments. However their execution times are extensive. Active protection systems need to make very fast predictions, before a fast attacking weapon hits the target. Fast execution times are also needed in real time simulations where the impact of many different computer models is being assessed. Hence, FEA explosion models are not appropriate for these real-time systems. The research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an explosion. In addition, the size and shape of fragments, unavailable in Mott’s equation, are calculated using photographic evidence and a distribution of a fragment’s length to its width. The model also identifies the origin of fragments on the warhead’s casing. The results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation steps. The developed model then can be made available for real-time simulation and fast computation.

Hearing disability is commonly observed in old age person. It is observed that for the age limit 55 to 80 years around 40% of individuals are facing age related hearing loss. Light weight hearing aid made of composites are being used very frequently. There are two types of hearing aids canal: In-the-ear (ITE), Behind-the-ear (BTE); out of which BTE is commonly preferred. Around 38% of BTE aids fail in their operation due to the impact generated by mishandling. Drop test measures the impact and fragility of the component. It particularly determines how the component performs under external the impact of the load. In the present study, drop impact numerical analysis has been carried out using ANSYS workbench explicit dynamic module for hearing aid casing. Three different polymer materials namely Acrylonitrile butadiene styrene (ABS), Polylactic Acid (PLA) and Thermoplastic Polyurethane (TPU) have been used. The main purpose of the analysis is to determine the maximum deformation and critical area when it falls on the ground. Load conditions like impact velocity and height have been considered as per the IS standard IS: 11052–1984 for the flat and side drop test. It is observed that maximum deformations were observed in TPU as compared to PLA and ABS irrespective of velocity. In addition, contact force was observed maximum in PLA and minimum in ABS irrespective of velocity which leads to minimum internal energy for PLA. TPU and ABS could be the second choice of material after PLA for the hearing aid casing.

Sustainable and renewable energy is the need of the hour. Scientists and Engineers around the world are pushing for electric vehicles and electrically run machines to save the environment from pollution and global warming, to create a sustainable planet for us humans to live. The aim of the present research work is to understand the heat transfer characteristics of an electric motor casing made of Aluminium Metal Matrix Composites (AMMCs) so as to implement such casings on a larger scale. As aluminium composites are light in weight, this would improve the performance and efficiency of the electric motor in the long run, and when thought about at the global level considering the new upcoming age of electric vehicles, the slightest of improvements could produce a major impact in the upcoming years. The CAD model of the casing is designed using Solidworks software. This model is used to conduct Finite Element Steady State Heat Transfer analysis in Ansys software to study the heat transfer characteristics. Five AMMCs are chosen for analysis. A comparative study is made based on the weight of the casing and the heat transfer characteristics for each material. Al/Graphite composite is found to produce promising results in the heat transfer domain.

A significant part of an automobile is the gear box (tractor) casing. The primary objective of using the Gearbox casing is to embrace and allow the transmission of the Gearbox. The Gearbox is a mechanism that regulates speed or torque between the flywheel and the differential. The main shaft and lay shaft with gears equipped embraces the gear box. This paper deals with the modeling and study as an alternative material of the gear box casing for a tractor with E-Glass. Through the development of the simulation software platform ANSYS, it is analyzed statically with different design parameters such as web thickness, gear box housing depth and gear box housing thickness. In order to determine the stress produced and deformation degree, the gear box with traditional Grey cast iron is analyzed; it is then compared with the housing of the E-Glass Gear box. The outcome will be studied and evaluated after study, various combinations of design parameters were used to achieve the design that minimum output in failure at higher load s has better deformation characteristics. Finally, in order to design the gear box housing, an optimized design parameter is obtained.[1]

Controlled-source electromagnetic (CSEM) measurements are complementary data for magnetotelluric (MT) characterization although its methodology on land is not sufficiently developed and tested as in marine environments. Acquiring expertise in CSEM is crucial for surveys in places where MT cannot be performed due to high levels of cultural noise. To acquire that expertise, we perform CSEM experiments in the Vallès fault [Northeast (NE), Spain], where MT results have been satisfactory and allow us to verify the CSEM results. The Vallès basin is relevant for potential heat generation because of the presence of several geothermal anomalies and its nearby location in urban areas. In this article, we present the experimental setup for that region, a 2-D joint MT+CSEM inverse model, several 3-D CSEM simulations in the presence of metallic casing, and its comparison with real data measurements. We employ a parallel and high-order vector finite element algorithm to discretize the governing equations. By using an adapted meshing strategy, different scenarios are simulated to study the influence of the source position/direction and the conductivity model in a metallic casing presence. An excellent agreement between the simulated data and analytical/real field data demonstrates the feasibility of study metallic structures in realistic configurations. Our numerical results confirm that metallic casing strongly influences electromagnetic (EM) responses, making surface measurements more sensitive to resistivity variations near the metallic structure. It could be beneficial getting higher signal-to-noise ratios and sensitivity to deep targets. However, such a casing effect depends on the input model (e.g., conductivity contrasts, frequency, and geometry). This work was been developed in the frame of GEOURBAN project (PCI2018-092943 and PCI2018-093186). This work has received also partial funding from the European Union's Horizon 2020 programme under the Marie Sklodowska-Curie grant agreement N777778. Also, the research leading to these results has received funding from the European Union's Horizon 2020 programme, grant agreement N828947, and from the Mexican Department of Energy, CONACYT-SENER Hidrocarburos grant agreement N B-S-69926. Furthermore, this project has been 65% cofinanced by the European Regional Development Fund (ERDF) through the Interreg V-A Spain-France-Andorra program (POCTEFA2014-2020). POCTEFA aims to reinforce the economic and social integration of the French-Spanish-Andorran border. Its support is focused on developing economic, social and environmental cross-border activities through joint strategies favouring sustainable territorial development. The authors would like to thank the Editors-in-Chief and to both reviewers for their valuable comments and suggestions that helped to improve the manuscript’s quality. This work benefitted from the valuable suggestions, comments, and proofreading of Dr. Josep de la Puente (BSC).

It is important to increase the production rate of oil and gas as the usage of them is increasing day by day. To increase the production rate of oil and gas, design of an efficient centrifugal pump impeller plays very important role. Due to the usual submergible pump, there might be the chances for failure and it is so complex when the pump is failed. So an alternative method such as artificial lift is necessary on behalf of submergible pumps for different flow rates. In the present study, 3D simulation of impeller and its stationary flow of centrifugal pump casing are analyzed using CFD. Pressure head and efficiency of the pump for different flow rates are analyzed as well as the data from pump manufacturers are taken and have good satisfactory agreement. Finally, the structural analysis of single impeller blade is carried out by changing different materials. These data are very useful to design the pumps in manufacturing industries.

Основной причиной возникновения посадок, затяжек и прихватов являются наличие большого количества глинистых минералов, несоответствие свойств и состава буровой промывочной жидкости, а также режима промывки геолого-техническим условиям вскрытия пласта. Прихват – это распространенный и серьезный вид осложнения при проводке скважины. Ликвидация прихвата требует значительных затрат времени и финансовых средств. Рассмотрены виды прихватов, признаки возникновения и мероприятия по их устранению. Установлена верхняя граница прихвата свободной части колонн по упругому удлинению, растягивающей нагрузке, собственного веса колонн. Даны алгоритмы определения вида прихвата и последовательности действий при ликвидации прихвата бурильной колонны., The main reason for jamming, dragging and sticking are plenty of clay minerals, inconsistency of properties and composition of drilling flushing fluid as well as non-compliance of the flushing mode with the geological and technical conditions of reservoir opening. Sticking is a common and serious drilling complication. It takes considerable time and money to eliminate sticking. Types of sticking, signs of their occurrence and measures for their elimination are considered. The upper limit of sticking of a free part of drill-strings by elastic elongation, tensile load, own weight of the strings is established. The algorithms for determining the type of sticking and the sequence of operations to eliminate differential wall sticking are given., Управление техносферой, Выпуск 4 2023

В статье предлагается применение метода сейсмоэлектрического каротажа для определения интервалов и качества перфорации обсадных колонн в нефтяных скважинах при оценке гидродинамической сообщаемости пласта с внутренней полостью обсадной колонны, основанного на изучении и анализе взаимодействия сейсмического и электрического полей – сейсмоэлектрического эффекта второго рода, возникающего преимущественно во флюидонасыщенных осадочных горных породах в результате их электризации при относительном смещении твердой и жидкой фаз при акустическом воздействии. Описываются физические предпосылки, определяющие возможности применения сейсмоэлектрического каротажа для решения задачи определения границ интервалов и качества перфорации обсадных эксплуатационных колонн. Автором осуществлена реализация способа определения границ интервала и качества перфорации обсадной колонны в скважине путем практического применения аппаратуры сейсмоэлектрического каротажа на нефтяном месторождении Оренбургской области для повышения точности и информативности геофизических исследований. Дается краткое описание аппаратуры сейсмоэлектрического каротажа: принцип действия, состав, методика измерений и результаты применения на месторождении. На основе анализа результатов полученных каротажных диаграмм обоснована целесообразность применения мегаэлектродного блока – группы 24 измерительных электродов в глубинном скважинном приборе, расположенных радиально оси прибора на прижимном устройстве, и акустического воздействия на исследуемую зону перфорации при регистрации диаграмм разности электрических потенциалов обсадной колонны для определения границ интервала и качества перфорации. Реализация способа определения границ интервала и качества перфорации обсадной колонны в скважине повышает интерпретационную информативность геофизических исследований и позволяет с более высокой объективностью судить о качестве проведенных прострелочно-взрывных работ в скважинах., The article proposes the application of the method of seismoelectric logging to determine the intervals and the quality of perforation of casing strings in oil wells when assessing the hydrodynamic connectivity of the formation with the inner cavity of the casing column, based on the study and analysis of the interaction of seismic and electric fields – the seismoelectric effect of the second kind, which occurs mainly in fluid-saturated sedimentary rocks as a result of their electrification with a relative displacement of the solid and liquid phases under acoustic influence. The paper describes the physical prerequisites that determine the possibilities of using seismoelectric instrumentation to solve the problem of determining the boundaries of intervals and the quality of perforation of casing production columns. The author has implemented a method for determining the boundaries of the interval and the quality of casing perforation in a well through the practical application of seismic logging equipment at an oil field in the Orenburg region to increase the accuracy and informativeness of geophysical studies. A brief description of the seismoelectric logging equipment is given: the principle of operation, composition, measurement technique and results of application at the field. Based on the analysis of the results of the obtained logging diagrams, the expediency of using: a megaelectrode block – a group of 24 measuring electrodes in a deep borehole device, placed radially along the axis of the device on a clamping device and acoustic effects on the perforation zone under study when registering diagrams of the difference in the electrical potentials of the casing string to determine the boundaries of the interval and the quality of perforation. The implementation of a method for determining the boundaries of the interval and the quality of casing perforation in a well increases the interpretative informativeness of geophysical studies and allows for a higher objectivity to judge the quality of drilling and blasting operations in wells., ГЕОФИЗИКА, Выпуск 1 2023, Pages 71-76

Cementing is one of the important steps in well construction. This chapter shows how to calculate the amount of additives required for mixing the different types of cement slurries. These additives provide properties of fluid loss, setting time and rate (i.e., acceleration or retardation), and reducing the friction to prevent high pump pressures on deep high-density casing jobs. Calculations to provide the proper placement for support of the casing and to ensure that the casing is anchored to prevent casing shoe movement after the cement is pumped are detailed. Other important cementing operations include pumping and placing open hole plugs and balancing the pressures, so the plug will not “U-Tube” when the pipe is removed from the plug. Finally, it is important to determine if the casing will move up (called “hydraulicing”) the hole as the different density cement slurries are pumped in place.

International audience; Lithium molybdate single crystals up to one kilogram have been grown by a conventional Czochralski process. The growth configuration (geometry, coil, crucible, insulation casing) was optimized by numerical simulation of heat and mass transfer. Dislocations are shown to belong to the basal glide system. Their density (≤ 10 4 cm-2) and luminescence properties indicate crystal quality similar to that of previously reported crystals grown by Czochralski technique. Numerical simulation of thermo-elastic stresses suggest that the crack observed in one of these crystals is rather due to a mechanical accident than to internal stresses during growth.

In this paper, a failure evaluation criterion was proposed for the bolted casing-flange structure under impact loading. Subsequently, ballistic tests with eighteen bolted casing-flange structure specimens were conducted to validate the failure evaluation criterion. Parameter studies were then carried out using the validated FE models. Both the experimental and numerical results demonstrated the accuracy of the failure evaluation criterion. The failure evaluation criterion provided a quick and easy way to determine the failure mode of the casing connection area by using the materials and dimensions of the structure. Based on the failure evaluation criterion, designing the structural failure mode of the bolted casing-flange structure to be between flange failure and bolt failure can improve the impact resistance of the connection area of the aero-engine casings. This investigation revealed that the impact failure is not the unique criterion in evaluating the containment of the casing connection area, structural failure should also be involved in the evaluation criteria.

Preflex beam girders with remarkable advantages are widely used in bridge structures. With aging, preflex beam bridges undergo concrete cracking and degrade as the cracks propagate and deteriorate due to repeated service load application and exposure to humid and saline environment. The objective of this study was to evaluate concrete cracking, changes in prestress, and consequent changes in sectional properties as the preflex beam undergoes deterioration in its concrete casing under cyclic loading. The experimental study investigated the behavior of a preflex beam specimen under multiple cyclic loading ranges, reproducing different deterioration levels in the concrete casing of the specimen. Relating concrete deterioration to resulting changes in the girder’s structural behavior, the study outlined recommendations for monitoring approaches in actual bridges. The study concluded that with advancement in concrete deterioration, the preflex beam girder loses prestress that results in reduced strength of the girder and remarkable changes in its sectional properties. The study also concluded to minimize prestress loss and changes in sectional properties of the girder, closer spacing for shear ribs welded to the lower flange can be helpful., 論文

Submarine pressure hulls, fire-tube boilers, vacuum tanks, oil well casings, submersibles, underground pipelines, tunnels, rocket motor casing, etc., are some of the examples of thin cylindrical shell structures which collapse due to buckling under uniform pressure. To enhance the buckling strength of bare cylindrical shells, one of the best solutions is to stiffen them with ring stiffeners. In this work in order to predict the shell instability failure mode (SIFM) and general instability failure mode (GIFM) FE models are generated and analysed using buckling analysis of general-purpose FE software ANSYS. The numerical results obtained using FE analysis are compared with published analytical and experimental results. Hence in the present study efforts are taken to develop FE models to predict global and shell instability failure modes of externally ring stiffened cylindrical shells by using linear FE analysis. It is proposed to use full/half bare cylindrical shell FE models (L/R ratio upto 200) to determine SIFM and FE models with shell281- Beam189 (for stiffeners) can be used to determine GIFM. The developed FE models are validated by comparing numerical results with experimental results published by Seleim and Roorda [25] . By using both proposed FE models it is possible to predict the failure modes namely SIFM and GIFM, comparing their values of critical buckling pressures. The lower pressure value can indicate the possible failure mode.

Assembly quality of aero-engine casing plays a key role in the whole aero-engine, since it is directly related to the final function and dynamic performance. However, during the design phase, the tolerance analysis is usually conducted independently without any consideration of the effect on the dynamic characteristic. This paper aims to integrate manufacturing precision with dynamic performance instability together. First, the 3-D tolerance model of the aero-engine casing is constructed based on the Jacobian-Torsor theory. The target deviation from the tolerance model is defined as the input variable into the vibratory governing equation. Then, the effect of 3-D assembly deviation on the natural frequency is studied. The corresponding frequency distributions for different vibration modes are illustrated. Finally, the mapping relationship between assembly tolerance and fluctuation ratio of natural frequency is established through the 3-D fitted surface. Under the given constraint of performance stability, the optimized tolerance zone is obtained. This work provides a significant guidance for performance improvement and tolerance design in the aero-engine casing assembly.

A pump is a machine that imparts mechanical energy to a fluid flowing through it, to move it from one point to another. This paper reports the design, manufacture and testing of a centrifugal water pump having a circular casing. A single stage, end suction centrifugal pump designed and manufactured, using locally sourced materials. This pump finds application in homes, agriculture and industries. It consists of an impeller, shaft, suction and delivery pipes and an electric motor. Experiments performed with this pump shows that it can deliver 0.0045m3 of water per second with a pressure head of 34.7m. A 2.5kW electric motor running at a speed of 2900rpm was used to drive the pump.

Present study entitled was carried out in field irrigation lab, Department of Agricultural Engineering, Aditya Engineering College, Surampalem. In the present experiment locally available agricultural substrate paddy straw, sugarcane bagasse and cocopeat were tested with black soil and farm yard manner as casing materials. For parameters such as days required for spawn run, pinhead formation, harvest days, total yield and biological efficiency were determined. Significant results were obtained for all the experimental parameters and also for the stem length and cap diameter. Best substrate found was the paddy straw in the recent experiment with days required for spawn run (14 days), pin head formation (11.2 days), days for first harvest(50 days), stem length (8.07 cm), capdiameter (8.67 cm), first harvest (489.45 gm), second harvest (453.68 gm), total yield (925.24 gm), biological efficiency (94.31%). The next best in the order was coco peat followed by sugarcane bagasse. Hence this study confirms the suitability of paddy straw for cultivation to mushroom growers and farmyard manure with 15 cm casing thickness as substrate for its cultivation for achieving higher yield. The benefit cost ratio was estimated as 1.57.

Актуальность исследования обусловлена необходимостью предотвратить введение в прифильтровую зону объема породы с большей однородностью и большего размера по сравнению с крупной фракцией пластового песка - попытка добиться улучшения фильтрационных свойств прифильтровой зоны, т. е. снижения [zeta]2фк и [zeta]2n. Конструкция гравийной набивки одновременно должна исключать вынос частиц пласта в скважину. Решение этой проблемы позволит улучшить работу фильтрации пластовой жидкости из пласта в скважину и сократить затраты на дополнительное применение методов интенсификации притока пластовой жидкости к скважине. Цель: разработать методику, позволяющую при выборе конструкции фильтра, одновременно с возможностью обеспечения им надежной гидравлической связи в системе пласт-фильтр, предотвращать вынос песка в скважину. Объекты. Для предотвращения поступления песка из пласта и удержания гравия на забое скважины при создании гравийных набивок применяют щелевые, проволочные, кольцевые, титановые, металлокерамические и другие фильтры. Эти фильтры, установленные в интервале перфорации обсадной колонны без образования гравийной наружной кольцевой набивки (а именно таким образом в большинстве скважин устанавливаются фильтры на месторождениях России), очень часто забиваются пластовым песком, что приводит к снижению продуктивности скважин. Если для задержания песка используются щелевые фильтры, то эффективность их применения зависит от соответствия размера щелей гранулометрическому составу выносимого песка. Фильтры с ракушечной набивкой более эффективны, но также не всегда отвечают поставленной цели, поскольку прочность и качество ракушечника, закачиваемого в прискважинную часть пласта, довольно низкие. Кроме того, примененные на промыслах проволочные фильтры не имеют фиксации каждого витка, в результате чего при механическом повреждении одного из витков происходит срыв всей намотки. Методы. При применении предложенной методики полученные результаты экспериментальных работ по оценке способов снижения выноса песка из несцементированных неоднородных пластов показывают, что применение фильтров в обсаженном стволе требует создания гравийной набивки в кольцевом зазоре между фильтром и колонной, в перфорированном канале и за обсадной колонной. Причем размер гравия должен быть выбран таким, чтобы исключить перемешивание гравийной обсыпки с пластовым песком за счет миграции и интрузии песка, т. е. D/d=4-5. Снижения производительности скважин можно в этом случае избежать путем увеличения размера и количества перфорационных отверстий. Следует отметить, что предотвращение выноса песка означает, что при оптимальном установившемся режиме работы скважины фильтр удерживает частицы скелета пласта, но пропускает мелкодисперсные и глинистые частицы. В период запуска скважины картина несколько иная - пропускается и часть скелетообразующих частиц до того момента, пока на фильтрующей оболочке не образуется естественный фильтр из отсортированных крупных фракций. Результаты. Частицы, которые составляют структуру породы, не должны выносится из пласта за счет применения фильтра. Практически это означает, что фильтр должен не пропускать 75-85 % (по весу) более крупных фракций песка. Для сохранения общей устойчивости скелета пласта можно допустить вынос мелких частиц не более 15-25 % (во весу). The relevance of the study is caused by the need to prevent the introduction of a volume of rock with greater homogeneity and larger size into the near-filter zone compared to the coarse fraction of formation sand - an attempt to improve the filtration properties of the near-filter zone, i. e. decrease in [zeta]2фк and [zeta]2n. The design of the gravel pack should simultaneously exclude the removal of formation particles into the well. The solution to this problem will improve the work of filtration of formation fluid from the formation into the well and reduce the cost of additional application of methods for stimulating the inflow of formation fluid to the well. Purpose: to develop a methodology that allows, when choosing a filter design, simultaneously with the ability to provide them with a reliable hydraulic connection in the reservoir-filter system, preventing sand removal into the well. Objects. To prevent the flow of sand from the formation and retain gravel at the bottom of the well, when creating gravel packs, slot, wire, ring, titanium, cermet and other filters are used. These screens, installed in the casing perforation interval without the formation of gravel outer annular packing (and this is how screens are installed in most wells in Russian fields), are very often clogged with formation sand, which leads to a decrease in well productivity. If slot filters are used to retain sand, then the effectiveness of their application depends on the correspondence of the slot size to the granulometric composition of the sand being removed. Filters with shell packing are more effective, but they also do not always meet the set goal, since the strength and quality of shell rock pumped into the near-wellbore part of the formation are rather low. In addition, wire filters used in the fields do not have fixation of each turn, as a result of which, if one of the turns is mechanically damaged, the entire winding breaks down. Methods. When applying the proposed technique, the results of experimental work on evaluating ways to reduce sand production from unconsolidated heterogeneous formations show that the use of filters in a cased hole requires the creation of gravel packing in the annular gap between the filter and the string, in the perforated channel and behind the casing. Moreover, the size of the gravel should be chosen so as to exclude the mixing of the gravel packing with the formation sand due to the migration and intrusion of sand, i.e. D/d=4-5. A decrease in well productivity can in this case be avoided by increasing the size and number of perforations. It should be noted that sand avoidance means that under optimal steady state well operation, the filter retains formation backbone particles, but allows fines and clay particles to pass through. During the well start-up, the picture is somewhat different - part of the skeletal particles is also passed through until a natural filter of sorted coarse fractions is formed on the filtering casing. Results. The particles that make up the rock structure should not be carried out of the formation by applying a filter. In practice, this means that the filter should not pass 75-85 % (by weight) of the larger sand fractions. To maintain the overall stability of the formation skeleton, it is possible to allow the removal of small particles not more than 15-25 % (in weight).

In view of the geological characteristics of high pressure in salt-gypsum formation of deep wells in Tarim Piedmont structure, high-density oil-based drilling fluids are widely used, which makes it difficult for subsequent cementing work. In order to solve the technical difficulties of cementing high-density oil-based drilling fluid and salt-gypsum formation in KS well, which is a key exploration well in this area, through analysis of cementing technical problems, combined with salt-gypsum formation cementing and deep well ultra-deep well cementing technology, targeted measures before casing running, optimization of flushing aggravated isolating fluid and aggravating agent are carried out. In addition, relevant technical measures are put forward based on the optimization of cement slurry additives, the design of slurry formulation pipe string structure and the optimization of cementing technology. A set of flushing aggravating isolating fluid was prepared by introducing small particle size, concentrated superfine aggravating agent and hematite powder with relatively large particle size, and a set of high-density cement slurry with good comprehensive performance was obtained by optimizing cement slurry additives and introducing super high-density aggravating agent GM-1. In order to ensure the safety of cementing, the adaptability test of cement slurry formula was carried out, focusing on the adaptability test of cement slurry temperature and density: when the temperature changes + 5 °C the density increases + 0.03 g/cm3, the thickening time of the system changes less than 44 min, the system has good stability, and the anti-channeling performance of cement slurry SPN is less than 3, which has good anti-channeling function and meets the construction requirements, At the same time, the compatibility experiments of different proportions and different media and the simulated intermittent cementing experiments are added to meet the requirements. Field application of KS well shows that the technology can meet the cementing requirement of oil-based drilling fluid in Piedmont area.

This study is designed to determine the H 2 S origin in the Ordovician Ma5 Member of Daniudi gas field and study the corrosion behavior of N80, P110 and N80S tubing and casings in medium-sulfur content HE16, micro-sulfur HE3 and low-sulfur HE1 gas wells. Therefore, method of weight loss of coupon on site were used to determine the corrosion rate. Similarly, SEM, XRD and EDS analyses were employed to know the corrosion products while establishing the relationship with H 2 S formation conditions. Results of this study show that, as the production time increases, there was initial increase in the volume of H 2 S before it finally decreases. Among the different sulfur gas wells, the corrosion rate of the HE16 is the largest, followed by the low-sulfur HE3 and the micro-sulfur HE1 (smallest). Within a gas well there exist a proportional relationship where higher partial pressure of H 2 S leads to higher corrosion rate. Generally, there is a trend of initial increase followed by decrease in the corrosion temperature of the gas wells in order of decreasing sulfur content (HE16, HE3 and HE1 well). Thus, the average corrosion temperature changing-rate of N80, P110, N80S pipe in the medium sulfur content well area, low sulfur content and micro-sulfur wells are 15.13%, 31.01% and 49.45% respectively. Although, the wells have some coupon corrosion products in common, there is still some basic differences in the composition of the HE1 wells (FeCO 3 and CaCO 3), HE3 wells (FeCO 3, FeS and CaCO 3) and HE16 wells (FeCO 3, FeS 0.9 , FeS and CaCO 3). These corrosion products are clearly stratified in the HE16 and HE3 wells, while no stratification occur in the HE1 wells. The densely structured FeCO 3 is well-distributed within just as the loose and poorly-converted sulfides are distributed on the surface. Both uniform and local corrosion exist simultaneously in the study area. The galvanic corrosion between the product substrate as well as the pitting caused by the inorganic salt result in local corrosion. In the micro-sulfur gas well, only uniform corrosion occur to form FeCO 3 as the corrosion product. For future development of the M5 member of Daniudi gas field, N80 tubing and casing is recommended for the micro-sulfur gas well, P110 or N80S material tubing and casing for the low sulfur gas well and N80S oil jacket for the sulfur gas well. It is good to note that special attention should be paid to the influence of temperature changes on the corrosion rate of the tubing and casing in the low-sulfur and medium-sulfur well zones.

Shear deformation often occurs during multistage fracturing of shale gas worldwide, increasing the operation cost of gas well completion and lowering the well’s productivity; strike-slip fault slippage is thought to be a crucial underlying factor. This paper presents a detailed analysis of the influence of strike-slip fault slippage on casing inner diameter and establishes a technique for predicting casing inner diameter after fault slippage. Numerical simulation models were developed to simulate the process of fault slippage and calculate changes in the inner diameters of the casing, considering different engineering and geological conditions. The influential factors, including the fault strike angle, slip distance, radius-thickness ratio, and mechanical properties of the formation, were analyzed in engineering practice; the simulation results were shown to be consistent. Four methods, including adjusting the wellbore trajectory of shale gas horizontal wells, avoiding perforation at the formation interface, decreasing the fracturing parameters including the fracturing pressure, discharge capacity, volume of injecting fracturing fluid, and prediction of casing inner diameter after casing shear deformation, were proposed and verified through engineering application and theoretical calculation, respectively.

Based on the health, safety, and environment (HSE) aspect, specific regulations of CO2 injection wells for enhanced oil recovery (EOR) and carbon capture, utilization, and storage (CCUS) must be carefully prepared before its implementation. In 2019, the Asian Development Bank as a donor institution provided a technical assistance grant for Battelle Memorial Institute to perform an initial review and evaluation done per field basis of Indonesian first pilot project CO2-EOR and CCUS at Sukowati Field, East-Java. This field has many challenges: reservoir fluid containing 20%–25% CO2 and 3%–4% H2S, total lost circulation issues in interest zones, and complex unsolved problems during the drilling operation. However, based on the industry standards and experiences worldwide, obtaining knowledge, referring to standards, and evaluating per well basis are mandatory to be conducted especially for a pilot project. Therefore, this first per well basis study in Indonesia aimed to improve per field basis Battelle’s review and analyze the results based on the experiences and lesson learned from countries that have applied CO2-EOR/CCUS. The findings of this study can help for a better understanding of the actual condition of the well integrity, particularly related to borehole and casing, and its appropriateness for the planned CO2 injection operation. The results will also be used for designing well integrity and well barrier; thus, well lifetime can be designed based on engineering and economic feasibility. Furthermore, these results will be used to support the regulatory bodies in making regulations for design, operation, lifetime monitoring, and mitigation as well as to be used by the operator.

Design of Radial Passive Magnetic Bearings with Active Dampers (Radial PMB-AD) and their application in a down-hole natural gas compressor (DHGC) are discussed. These compact and reliable bearings allowed non-contact suspension of a high-speed DHGC rotor spinning at 50kRPM in a highly adverse environment more than 3km (10,000 ft) below the ground with temperatures reaching 100 degrees C. The design was further complicated by the space limitations imposed by a well casing. The paper presents the design of PMB-AD modules, as well as their integration and testing as a part of a DHGC.

During the fracturing process of oil and gas wells, casing eccentricity directly affects the mechanical integrity of cement sheaths, but the law and degree of influence are not clear at present, and there are no measures to address the influence of casing eccentricity on the mechanical integrity of cement sheaths. This paper took the lead in developing a set of experimental devices for cement sheath integrity. A comparative experimental study on the mechanical integrity of cement sheaths was carried out for the first time under casing concentric and eccentric conditions, and the influence of casing eccentricity on the mechanical integrity of cement sheaths in fractured wells of the Wushi 17-2 oilfield was also investigated. The numerical simulation method was used to perform stress analysis on cement sheaths of fractured wells under casing concentric and eccentric conditions. The influences of casing wall thickness, cement sheath thickness, the elastic modulus of cement sheath, and formation on radial stress of the cement sheath were analyzed, and the mechanical integrity safeguard or remedy measures of the cement sheath under the casing eccentric condition were proposed for the first time. The results show that casing eccentricity can easily lead to stress concentration at the narrow edge of the cement sheath. Under the condition of the same strength of the cement sheath, the integrity of the cement sheath is more likely to fail under the casing eccentric condition. The tensile failure cracks are concentrated at the narrow edge of the cement sheath. With the increase in casing eccentricity, the stress at the narrow edge of the cement sheath increased, the critical failure pressure of the cement sheath decreased, and the failure pressure of cement sheath integrity decreased by 17.72% at a casing eccentricity of 33% compared within a casing eccentricity of 0%. Improving the casing center degree, increasing the casing wall thickness and cement sheath thickness, and reducing the elastic modulus of the cement sheath can minimize the stress of the cement sheath and prevent mechanical integrity failure. This study is helpful to evaluate the mechanical integrity of the cement sheath in fractured wells accurately and can provide a technical reference for optimizing the casing center degree.

Short fillet welds used to fasten a large retainer ring to so-called dog bone seals failed in the turbine exhaust casing of a non-OEM heavy-duty gas turbine engine used for power generation. The subject fillet welds fractured due to high cycle fatigue loading. Neither weld imperfections nor any other material defects were found that could have contributed to the failure. It was concluded that an unfavorable design, specifying very short fillet welds for fastening the dog bone seal segments to the retainer ring, was the root cause of failure. In a purely static loading situation, this design would probably not have failed. However, in a dynamic loading scenario as is the case in any gas turbine engine exhaust, such a design is simply not sturdy enough.

Studies were conducted to evaluate leached sawdust as a casing substrate for the cultivation of Agaricus bisporus either alone or in combination with other substrates at College of Horticulture and Forestry, Neri, Hamirpur, Himachal Pradesh, India during the year 2018–2020. Out of seven casing media evaluated alone, coconut coir pith performed best in terms of all production parameters like time for spawn run (20.3 days) and pinning (15.7 days), sporocarps’ number (55.33), yield (0.679 kg 5 kg-1 compost) and biological efficiency (33.95%). The efficiency of sawdust- leached improved with the addition of other casing substrates. In commercial trial, combination of sawdust - leached with coconut coir pith, spent compost and farmyard manure (1:1v/v) performed better as compared to control (FYM+local soil), but a combination of sawdust- leached+coconut coir pith (1:1v/v) proved to be the best in terms of sporocarps’ number (88.00) and yield (1.271 kg 10 kg-1 compost) despite of the delay in time for spawn run (26 days) and pinning (24.3 days). Casing media also affected the biological efficiency of compost which varied from 10.50% in local soil to 34.05% in sawdust- leached+farmyard manure (1:1v/v) in different experiments. Cap diameter was recorded to be maximum (41.37 mm) in 2 years old spent compost and minimum (34. 27 mm) in sawdust- leached while, stipe length ranged from 14.17 mm in vermicompost-leached to 22.90 mm in sawdust- leached+farmyard manure (1:1v/v). However, fruit bodies harvested from all the casing treatments including standard check were found to be silky smooth and firm to compact.

One of the largest trap intrusion provinces, Siberian traps, is located in the East-Siberian Platform in Russia. A trap intrusion zone usually has abnormally low reservoir pressures and natural fractures. Consequently, trap drilling is associated with fluid losses that can be catastrophic. The section of trap intrusion is a part of a Ø 174 mm production casing section of the Srednebotuobinskoe field. The basic well design of this section also includes the Osinsky horizon, which features an abnormally high reservoir pressure zone. The latter creates incompatible with drilling conditions environment due to the presence of catastrophic loss zones in traps. Time spent on drilling a trap intrusion zone accounts for up to 30 % of the total well drilling time. The abovementioned geological issues in directional wells become the key topic in solving it. The method to resolve this issue is an integrated approach employing all the technologies and technical facilities aimed at finding a technological solution. First of all, in order to optimize the well construction cycles and reduce the complications, all the wells were classified in three categories as per the type of behavior in trap intrusion. This allowed to work out multi-level activities, that depended on severity of losses and non-operational time spent on drilling through this section. An alternative well design was developed and trialed on several wells, which showed positive results on decreasing non-productive timing. The main concept of this design was significantly different from the basic well design that was used in the past on the Srednebotuobinskoe field. The main difference was isolation of traps from the high pressure Osinsky horizon lower section with a Ø 245 mm casing string, which allowed safe splitting of two incompatible drilling zones. The economic effect of this solution allowed saving of up to 10.4 days or 15 % of the construction time in the wells of first category. These results were reviewed at the Technical Committee of the Company and agreed to implement the alternative well design on first category wells on the Srednebotuobinskoe field. In addition, for the rest of well categories the Drilling Team has produced and successfully implemented the preventative measures that allowed drilling through traps with lost circulation material. It is worth to mention that this method assumed a by-passing mud-cleaning system on the rig to allow building up a solid phase thus stemming the losses while drilling. For all the categories of the wells the Drilling team has selected and trialed different types and designs of drilling bits that would allow drilling hard rock such as dolerite section in traps with minimal number of runs. For the last five years the Drilling team together with the bit producing companies have designed a new type of PDC cutters that would allow to enhance durability as well as improve drilling speed both in dolerite formations and in overlying formations in the Production casing section. The Drilling team has also managed to reduce the number of trips associated with early bit wear decreasing them from five to two runs and create an experimental basis for drilling the entire section of the production casing in one run. From 2019 team continue looking for further solutions that would allow to improve bottomhole assembly elements balancing between durability and drilling rate in different types of formations above and below traps. A range of proposed technological solutions significantly reduced the impact on the well construction performance by preventing and reducing the downhole losses events in the section of trap intrusion on the Srednebotuobinskoe field.

The perforating technique is one of the well completion methods and a final stage that helps connect reservoir formation to wellbore during hydrocarbon production. The present work aimed to determine the effect of the perforated casing completion on the pressure gradient and perforation skin factor in the vertical near-wellbore region. This work presented a novel experimental approach for studying the effect of perforation parameters on hydrocarbon production by creating a prototype representing the near-wellbore region. The study conducted extensive laboratory testing to create two prototype artificial samples for a cylindrical near-wellbore region, open hole, and perforated casing sample. An experimental test was carried out using a geotechnical radial flow setup to measure the differential pressure in the two samples; the single-phase (water) was radially injected into the core sample within the same flow boundary conditions. Numerical simulation and statistical analysis were used to expand the investigation of the effect of the dimensions and distribution of perforations on the perforation skin factor and the pressure gradient in the cylindrical near-wellbore region. The results showed a clear view of the effect of the perforations’ parameters on the pressure gradient in the vertical near-wellbore region. In addition, two novel correlations were produced from statistical analysis that simplified the estimation of the perforation skin factor in the perforated casing completion. This study will help to clarify and understand the effect of perforation parameters on well productivity.

With the exploration of marine oil fields in deep and ultra-deepwater regions, the need for studying different methods of well construction has increased. Nowadays, the technique of laying conductive casing by jetting is the most widely used for the starting phase of a well in such conditions. In this scenario, in early layers, where the marine soil is in contact with seawater, this material can present itself as a fine mud, characterizing a cohesive non-drained soil, with low shear strength, being considered a material with viscoplastic behavior. Thus, as such, using fluid rheology to analyze it may represent a valid option; being possible to classify it as a Herschel-Bulkley fluid. The use of computational modeling and numerical simulation represent an alternative to understand the behavior of soil during jetting. In this context, this work focuses on developing a computational modeling of the jetting of marine soil, based on the soil fluid dynamics approach, using computational fluid dynamics (CFD - Computational Fluid Dynamics) software SIMULIA XFLOW, version 2020. This work aims to investigate the deformation in the seabed in response to an incident vertical jet using different drilling fluids, also modeled as viscoplastic materials. Drilling fluids suitable for jetting and a fluid with a higher specific mass were considered. For the proposed modeling of the soil and drilling fluids considered, the main parameters used were the yield point, consistency index, behavior index, and the boundary viscosity. The latter was necessary to implement the modified Herschel-Bulkley model used by the software. Results show that the excavated cavity presented a similar behavior for the drilling fluids suitable for jetting, indicating that the rheology of the drilling fluid does not interfere with the deformation of the soil. However, a significant influence on the profile of the excavated cavity was observed when implementing the drilling fluid of higher specific mass in the jetting, which deformed the soil at greater depths.

This paper aims to build a smart lighting system with applications such as remote for controlling power supply and optimizing heat management in the metal body of the semiconductor diode and with a printed circuit board for agriculture. The semiconductor diode strips with multiple colors are lined up and configured as a LED lamp with proper casing and heat sink. It has a driver circuit with required power regulation that is able to control the intensity of light for photosynthesis and plant growth requirements. The system uses hydroponics to plant the water, thus decreasing the usage of fertilizers. The entire system is controlled remotely using necessary communication interface application.

To effectively extract the information of compound faults of inter-shaft bearing of an aero-engine based on casing vibration signals, the paper has introduced the concept of weighted Katz fractal dimension and proposed the method combining information fusion, wavelet transform (WT), singular value decomposition (SVD), and Katz fractal dimension, the cross-correlation function (CCF-WT-SVD-Katz algorithm). The method includes homologous information fusion achieved by the CCF of horizontal and vertical vibration signals of the rotor from the same section; signal separation and denoising of blended signals through WT and SVD; reinforcement of fault characteristics of signals according to weighted Katz fractal dimension; and extraction of characteristic frequencies of compound faults of inter-shaft bearing by frequency spectrum of weighted and reconstructed signals. The result indicates that the proposed CCF-WT-SVD-Katz algorithm is capable of effectively extracting compound fault characteristics of inter-shaft bearing and precisely identifying a fault type based on whole casing vibration signals and will be of very good application value in engineering.

A fan-blade out (FBO) event may cause complex vibrations in an aeroengine. A fusing structure protects the structural integrity of the whole aeroengine after an extreme accident, such as a blade-loss event. In this paper, we investigate not only the transient and steady responses of a simulated aeroengine model with a fusing structure after an FBO event but also the changes made to the model because of the fusing structure. Our simulated model of an aeroengine includes two rotors, bearings, and a casing. The results for the dynamic response of the simulated model show that the fusing structure can reduce the steady-state response and the impact load on the support bearings in the rotor system. The rubbing impact between the blades and casing was accounted for. A fast method for calculating the response of fused structures was developed, which may be useful when designing the stiffness of the fusing structure.