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Journal articles on the topic 'Construction rigs'
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1
Macnar, Kazimierz, Andrzej Gonet, and Stanisław Stryczek. "Wybrane zagadnienia geotechniczne posadowienia urządzeń wiertniczych." Nafta-Gaz 77, no. 5 (May 2021): 313–22. http://dx.doi.org/10.18668/ng.2021.05.04.
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This article presents selected geotechnical issues occurring at the foundation of drilling rigs for geological works included in the Operation Plan of a company performing geological works, in the aspect of designing and construction of their foundations and a yard. In the construction of drilling equipment, at least two main zones can be distinguished, often requiring separate foundations for individual machines: the zone near the borehole, including crane components, mast and drill pipe drive, and the so-called machine hall zone, including drive units and elements of mud system. The machine foundation is designed to mount a particular type of machine on it in order to transfer to the ground the static and dynamic loads generated during the movement of the machine. In particular, the current legislation, technical literature and standards were reviewed, especially: API recommended practice 51R and 4G, Working platforms for tracked plant, Eurocode 7 PN-EN 1997-2:2009 Standard. The values of safe bearing capacity of some soils and the magnitude of pressures generated by static and dynamic loads of selected drilling equipment were presented, which can be useful for preliminary assessment of the location of drilling equipment in the field and selection of surface and type of foundations. Typical examples of foundation of drilling rigs in various geotechnical conditions on direct foundations with the use of prefabricated elements such as reinforced concrete road slabs, wooden slabs and composite slabs based on HDPE plastic or on indirect ones with the use of micropiles were described. The following essential elements of the process of geotechnical design of the foundation of drilling rigs and their execution were indicated. According to legal regulations, the form of presentation of geotechnical foundation conditions and the scope of necessary tests should depend on assigning the building structure to a proper geotechnical category, which for practical purposes is tabulated in this article. The design and construction of foundations for drilling rigs should ensure, among other things, that their intrinsic vibrations are sufficiently different from those induced by subassemblies of the rig, that the vibration amplitudes are smaller than permissible, and that the foundations of individual machines are adequately separated from each other and from the rest of the facilities (yard). Conclusions on the safe foundation of drilling rigs on the ground, including, among others, the strengthening of the ground, design of independent building structures such as foundations for drilling rigs and their execution and removal were presented.
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Han, Lei, Chuan Wu, Peng Zhang, and Jiang Hao Bai. "Trenchless Rig Remote Monitoring System Software Development Based on VB." Advanced Materials Research 945-949 (June 2014): 2762–66. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.2762.
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To guarantee the normal construction of trenchless rigs and increase enterprises’ managerial effectiveness of trenchless rigs all over the country, considering the construction characteristics of this kind of machine, the paper develops a upper-computer software of trenchless rig remote monitoring device based on VB. Through this software, it is convenient for enterprises to realize the real-time monitoring of trenchless rig information such as its application factors, geographical locations ,operating time and primitive parameters. Field experiment was conducted when software design for testability was finished, and the experimental data shows that this software can meet projects’ application requirements.Key words: VB; trenchless rig; monitoring; software
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Bai, Shixin, Zhijian Liu, and Jin Wang. "Research on the Dynamics of Geological Drilling Rig against Drill Pipe Impact." Shock and Vibration 2021 (January 29, 2021): 1–10. http://dx.doi.org/10.1155/2021/6679169.
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With the ever-increasing demand for resources, the task of geological surveys has increased rapidly, and automated geological drilling rigs that can improve the efficiency of geological surveys have become the mainstream research direction. Automated geological drilling rigs can improve construction efficiency, reduce labor intensity, and effectively reduce construction accidents. During the construction of geological survey operations, accidents such as drill breakage, stuck drill, and equipment damage, which are easily caused by drill pipe impact, occur from time to time. Therefore, drill pipe impact dynamics is currently a hot topic in academic research, but there are few studies that combine automated geological drilling rigs with drill pipe impact. This article starts with the research on the hydraulic system of the power head of the automatic drilling rig and studies the dynamics of the damage of the power head of the drilling rig caused by the impact of the drill pipe by means of hydraulic valve torque limit and closed-loop control of the speed. The oil valve group reduces the reverse torsional impact of the drill pipe on the hydraulic motor. At the same time, the requirements for the selection and pressure setting of the relief valve in the buffer filling oil valve group are proposed. The natural frequency of the relief valve is not less than 20 Hz, and the pressure is set to the working pressure 1.25 times. The effects of shock with or without the buffer filling oil valve group and the oil supply line on the power head motor were compared. The research results of this paper can provide theoretical reference and design basis for subsequent development of automated drilling rigs.
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Sarhan, Osamah, and Mahdy Raslan. "Offshore petroleum rigs/platforms: An overview of analysis, design, construction and installation." International Journal of Advanced Engineering, Sciences and Applications 2, no. 1 (January 31, 2021): 7–12. http://dx.doi.org/10.47346/ijaesa.v2i1.58.
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Jacket platforms are one of the most important and regularly used types of offshore structures for oil and gas extraction that have a big impact on the economy of the countries. In this paper, all aspects including design, analysis, construction and installing of the jacket type offshore structure, are summarized and classified. This type of structure is one of the specified platforms for shallow water, and for long term service, it also has the ability to carry large deck loads. This paper aims to present general guidance about the planning, design and construction of offshore jacket (template) platforms. Jacket platforms are fixed type platforms which are attached to the seabed using piles which provide stability against the wind, wave and current loads. Also, this type of offshore platform has a high initial and maintenance cost because of its exposure to corrosion, and cannot be reused after the end of its service period. Jacket platforms are most suitable for shallow water having no better alternative while it has the cost disadvantage for deep water.
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Masse, Frederic, Rick Deschamps, Alexandre Scarwell, and Thomas Joussellin. "IoT and Big Data in Geotechnical Construction: Connecting Drill Rigs to the Cloud." GEOSTRATA Magazine 25, no. 3 (May 2021): 30–35. http://dx.doi.org/10.1061/geosek.0000031.
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Kotwica, Krzysztof, and Grzegorz Stopka. "Drive simulation tests for electric drilling rig." New Trends in Production Engineering 2, no. 1 (October 1, 2019): 96–103. http://dx.doi.org/10.2478/ntpe-2019-0010.
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Abstract The article presents methodology and selected results of simulation tests of diesel and electric dive system for drilling rig. Research in this field were conducted under the project no. POIR.01.01.01-00-D011/16 entitled „New generation of modular rigs, drilling and bolting, with battery drives, designated to work in underground cooper ore and raw rock material mines”. The project is funded by the National Center of Research and Development (NCBiR). The aim of the project is to design and implementation of innovation drilling and bolting rig with electric drive system. Due to the complexity of the structure of the drive system (mechanical, hydraulic and electrical elements), it was necessary to use advanced simulation software dedicated to multiphysics analysis. Data presented in the article can be used as guidelines in design process of drilling and bolting rigs as well as in optimization their driving system and mechanical construction.
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Shepelev, A. A., and M. V. Kosnyreva. "GEOPHYSICAL RESEARCH AS PART OF ENGINEERING SURVEYS ON THE SHELF OF THE OKHOTSK SEA." Bulletin of Dubna International University for Nature, Society, and Man. Series: Natural and engineering sciences, no. 2 (47) (September 14, 2020): 51–59. http://dx.doi.org/10.37005/1818-0744-2020-2-51-59.
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The paper deals with the results of marine engineering surveys on the shelf of the Okhotsk Sea. According to the results of the study, potentially hazardous geological and technogenic objects were localized, and a network of buried river paleo–incisions was identified. The work performed allowed us to obtain materials that ensure the safe installation of floating drilling rigs for the period of well drilling, design and construction of oil and gas field facilities.
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Dang, Lin. "Construction and Application of a Static Load Performance Testing Platform for Truck-Mounted Drilling Rigs." Procedia Computer Science 166 (2020): 37–40. http://dx.doi.org/10.1016/j.procs.2020.02.009.
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Li, Dong. "Impact Analysis on Slip Strength Based on Fuzzy Analysis Hierarchy Process." Applied Mechanics and Materials 157-158 (February 2012): 800–804. http://dx.doi.org/10.4028/www.scientific.net/amm.157-158.800.
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In order to analyze the impact factors of slip strength in clamp devices for tunnel rigs in coal mine comprehensively and quantitatively, a multi-factor and hierarchy index system with 13 indexes were established, including 4 fields of driller, construction characters, technology and environment. Fuzzy Analysis Hierarchy Process (FAHP) was used to analyze slip strength. A simple method to construct fuzzy consensus matrix was introduced to obtain the weight of different factors. Result shows that FAHP is validated to be used in slip strength impact analysis.
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Grinchar, N. G., A. S. Shohin, and M. Yu Chalova. "Application of modern drilling machines in transport construction." Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta 6, no. 4 (December 25, 2020): 477–85. http://dx.doi.org/10.22281/2413-9920-2020-06-04-477-485.
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The broad scale of the plan for the development of the Far North, Siberia, provides for the annual development of hundreds of millions of cubic meters of permafrost soils and rocks, most of which require the use of drilling and blasting operations. The most time consuming process of preparing rocks for excavation is the creation of wells. Drilling of permafrost soils, soils with rock inclusions, monolithic and fractured rocks requires careful analysis and detailed calculations for each type of rock. It should also be borne in mind that the harsh climatic conditions of work in the Far North, open mining fields, also imply a significant distance from any settlements, therefore, based on the above factors, special attention should be paid to investigate the problems of mobility and reliability of tractor drilling rigs. This article discusses the use of modern drilling machines, provides a comparison of a tractor drilling rig with a mechanical drive of a drill string with a machine with a hydraulic drive, lists the factors confirming the feasibility of using a hydraulic drive of a drilling string, examines the results of tests of drilling various rocks, as well as the effect of rock structure on vibrations pressure and increase in the flow rate of hydraulic fluid in the drive system of the machine.
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Jurecki, Rafał, Edward Pokropiński, Dariusz Więckowski, and Łukasz Żołądek. "Design of a Test Rig for the Examination of Mechanical Properties of Rolling Bearings." Management Systems in Production Engineering 25, no. 1 (March 1, 2017): 22–28. http://dx.doi.org/10.1515/mspe-2017-0003.
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AbstractThe paper presents a design basis adopted for the construction of a test facility for the rig testing of rolling bearings. One of the methods of inspection of the bearings is the testing of the bearings as components having already been mounted in a specific machine component unit and tested in the conditions of operation of the unit as a whole. This article presents preliminary engineering requirements and the design of a special test rig for the examination of rolling bearings without the necessity of mounting the bearings in a specific machine component unit. The rig testing is widely used in consideration of numerous good points of such a method. The simulation testing of bearings (on test rigs) consists in reproducing as accurately as possible the real conditions of operation of the bearings when mounted in the device for which they are intended. The rigs used for such tests are complicated and expensive, but the results of such tests are more “reliable” and more accurately represent the impact of various operational factors (loads) on the durability of the bearings under test.
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Kuznetsova, N. A., A. A. Tetyushev, and I. M. Shandybina. "Basic Principles for the Construction of Dynamic Models of the Planetary Gears Used in Drilling Rigs." Chemical and Petroleum Engineering 53, no. 7-8 (November 2017): 450–52. http://dx.doi.org/10.1007/s10556-017-0361-3.
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Zhussupbekov, Askar, Ivan Morev, Gulzhanat Tanyrbergenova, and Nurgul Shakirova. "Evaluation of the quality of pile foundations by different methods." MATEC Web of Conferences 265 (2019): 05013. http://dx.doi.org/10.1051/matecconf/201926505013.
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At the present time, in Astana city is going on works by construction public transport system LRT (Light Railway Transport). LRT is an overhead road with two railway lines. The first stage of construction is including construction of overhead road (bridge) with 22.4 km length and 18 stations. The foundation of bridge is the bored piles with cross-section of 1.0-1.5 m and length of 8-35 m. A design bearing capacity of pile is 4500-8000 kN. Chinese drilling rigs Zoomlion was used for soil boring without casing. A polymer slurry is used to maintain the walls of boreholes in sand and gravel soils. In these conditions very important point is the integrity of concrete body of each bored piles. For checking the integrity was used two methods – the Low Strain Method and the Cross-Hole Sonic Logging. The aim of this paper is finding the advantages and disadvantages of each method which applying on testing site.
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Hong, Dae Sun, Do Un Kim, Hyo Jeong Kang, Sang Wook Hwang, and Sang Sik Lee. "Finite Element Analysis on a 250 kN.m-Type Rotary Drilling Rig for Foundation of Geological Construction." Key Engineering Materials 516 (June 2012): 545–50. http://dx.doi.org/10.4028/www.scientific.net/kem.516.545.
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Rotary drilling rigs, general construction equipment, are widely used for deep drilling of ground for the foundations of public works. A new 250kN.m-type rotary drilling rig, most widely used in this field, is under development, and this study focuses on the operational safety of the mast subassembly on the basis of structure analysis of the mast subassembly using a finite element method with ANSYS. When using a drilling rig, an electric rotary drive supplies power for drilling. Here, the elevation of the rotary drive along the mast needs to be changed according to the geological construction environment. Through the analysis, the allowable torques at various elevations of the rotary drive are evaluated, also the safety of the drilling tool called the kelly bar subassembly is examined. Finally, the suitability of the mast subassembly design is examined from the analysis results.
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Ivanova, Olga A., Irina L. Blagovidova, and Anna V. Rodkina. "CRITERIA SYSTEM FOR COMPARISON AND EVALUATION OF VARIOUS DRILLING RIGS TYPES APPLICABILITY UNDER SEVERE CLIMATIC CONDITIONS." Russian Journal of Water Transport, no. 65 (November 23, 2020): 37–53. http://dx.doi.org/10.37890/jwt.vi65.126.
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The article provides an analysis of existing multicriteria assessment methods. The hierarchy analysis method developed by T. Saati and the expert assessment method is proposed to structure the complex task of comparing and assessing the applicability of various drilling rigs types to extend the drilling season in severe climatic conditions under the influence of ice loads. The priority of the criteria for the hierarchy analysis method is based on an expert survey. The application of the expert assessment method allows taking into account the existing experience in the design and operation of offshore drilling facilities. Weights were determined based on the results of an expert survey using a simple mathematical apparatus. The program was developed in MS Excel to obtain a numerical assessment of criteria preferences. The results of the study can be used by design organizations at an early stage of design, i.e. for the conceptual stage of project development, with a significant lack of climatic and geological information about the construction site. The obtained results allow us to determine the most objective and effective form of choosing an acceptable option for the offshore structures construction, taking into account the possible minimization of its cost, ensuring safety and reliability for the entire operational period.
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Elsayed, M. A. "A Novel Approach to Dynamic Representation of Drill Strings in Test Rigs." Journal of Energy Resources Technology 129, no. 4 (May 7, 2007): 281–88. http://dx.doi.org/10.1115/1.2790979.
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Drill strings are used in oil and gas production as well as geothermal wells. They experience destructive vibrations, many of which are highly dependent on drill string modes. In this paper, we show that the lowest frequency modes are not necessarily the most critical and we delineate a methodology for reducing the number of modes representing the drill string. The frequency response function and stability diagram are used as measures of dynamic similarity between the proposed model and the drill string. We also introduce a novel approach to represent a drill string in laboratory test rigs. This approach not only represents the drill string dynamics but also offers flexibility to modify, remove, or augment the modes representing the system. The underlying principle is that in a multi-degree-of-freedom in-series spring-mass system with Rayleigh damping, dynamic modes can be decoupled. Applying the force to the end node (bit), the modes can then be configured separately in a parallel arrangement where their contributions to bit displacement are added algebraically. A practical arrangement for this purpose is proposed in this paper. Construction of a test rig that accurately represents the drill string dynamics is critical to validation of any test data on bits, bottom hole assemblies, instrument subs, and so on.
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Marriott, Ken. "Low Frequency Noise Problems on Oil & Gas Drilling Rigs." Journal of Low Frequency Noise, Vibration and Active Control 27, no. 3 (September 2008): 237–46. http://dx.doi.org/10.1260/026309208785844130.
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Parvaresh, Aida, and Mohsen Mardani. "MODEL PREDICTIVE CONTROL OF A HYDRAULIC ACTUATOR IN TORQUE APPLYING SYSTEM OF A MECHANICALLY CLOSED-LOOP TEST RIG FOR THE HELICOPTER GEARBOX." Aviation 23, no. 4 (March 5, 2020): 143–53. http://dx.doi.org/10.3846/aviation.2019.11869.
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Transmission health is an important factor in safety and maintenance costs in industries, so construction of test rigs for testing high-powered gearboxes under different operating conditions of helicopters is required. The studied test rig, which is developed at Sharif University of Technology branch of ACECR (Academic Centre of Education, Culture and Research) is mainly used for testing high-powered gearboxes through a mechanically closed-loop procedure. For providing a variety of speeds and torques in test rigs, torque applying system is required. According to generation of higher forces, reduced size of equipment and accurate positioning, electro hydraulic actuators (EHAs) are used for applying torques for planetary gearboxes of this test rig. Due to the importance of applying accurate torques in evaluation of the gearbox performance, first an accurate model of EHA is derived, which captures the system dynamics using system identification method with low consumed time and simple relations. After that, a type of model predictive controller called dynamic matrix controller is proposed for controlling EHA under determined requirements. Then, the performance of proposed controller under normal conditions as well as in presence of disturbance is investigated. The results show a good tracking of controller for various reference inputs in different conditions. Moreover, the performance of the proposed controller is compared with the performance of classical proportional-integral-derivative (PID) controller and superior characteristics of the proposed controller is concluded.
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Bursell, Jens Jakob, and Robert Arlinghaus. "Citizen science data suggest that a novel rig improves landing rate and reduces injury and handling time in recreational angling with artificial lures in Baltic pike (Esox lucius)." PeerJ 6 (May 17, 2018): e4744. http://dx.doi.org/10.7717/peerj.4744.
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The optimal terminal gear in hook-and-line recreational fishing maximizes landing rates and minimizes injury to the fish because some fish will be released after capture. We designed a novel rig configuration in artificial lure fishing for top predators and examined its effectiveness in angling for Baltic northern pike (Esox lucius) using a citizen science approach based on observational data collected from volunteer anglers in the field. The novel rig included two changes to traditional rig designs common to artificial lure angling. First, hooks were mounted in a way giving better hook exposure and eliminating lever-arm effects from the lure to the hooks once a fish is hooked. This construction allowed the second change, being a shift to hooks 4–5 sizes smaller than those used on traditional hook mounts. We analysed observational data collected by volunteer anglers using either the novel rig or a standard rig mount in two types of artificial lures (softbait and hardbait) of the same size (about 17 cm). UsingN = 768 pike contacts as input data, we showed the landing rates of pike targeted with artificial lures significantly and substantially increased from 45% with normal-rigs to 85% when the same lure types were fished with the novel rig configuration. Lure type and water temperature had no effects on landing rates. Moreover, hardbaits on normal-rigs produced significantly more injury, bleeding and elevated unhooking time compared to fish captured on hardbaits with release-rigs. We conclude that simple changes to traditional hook sizes and mounts in lure fishing may benefit both anglers and the fishes that are to be released and that citizen science projects with volunteer anglers are able to provide good data in proof-of-concept studies. Further experimental studies are needed to differentiate hook size from hook mount effects because both variables were confounded in the results of the observational data presented here.
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Song, Yue, Yang Qu, Nian-Zhong Chen, and A. V. Metrikine. "Effect of immersion depth on the coupled dynamics of a tunnel-rigs system in irregular waves." Tunnelling and Underground Space Technology 115 (September 2021): 104068. http://dx.doi.org/10.1016/j.tust.2021.104068.
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Leksin, V. K., V. I. Samarin, and P. N. Liskovyi. "RESULTS OF INTERPRETATION OF SEISMIC SECTIONS DURING ENGINEERING SURVEYS WITHIN OF THE SOUTH-KIRINSKOYE OIL AND GAS CONDENSATE FIELD (SHELF OF SAKHALIN ISLAND)." Engineering survey 12, no. 9-10 (April 4, 2019): 64–73. http://dx.doi.org/10.25296/1997-8650-2018-12-9-10-64-73.
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High-resolution 2D seismic is the main and optimal method in marine engineering geophysics, which for many years has worked well for the production of semi-submersible drilling rigs, self-lifting drilling rigs, construction of berthing facilities and bridges. The main objective of this method is to identify near-surface gas, faults, which are geological hazards. The method used for performing marine research is longitudinal profiling of reflected waves with a 48-fold overlap of the reflecting horizons. To obtain high-quality seismic migrated sections, we have previously developed a unified data processing algorithm for the offshore areas of the South-Kirinskoye oil and gas condensate field (Sakhalin shelf). More than 8,000 line km of seismic data were processed. The article presents the sequence of interpretation, as well as an analysis of the presence of hazards in the project wells (objects). To isolate potentially dangerous objects for each horizon, a dynamic analysis was carried out, which included the definition of the following parameters: maximum and minimum peak amplitude. The systematization and classification of amplitude anomalies was carried out according to such features as a phase change, frequency reduction, the presence of a supply channel and distortion (false deflection) of all underlying boundaries, indicating the possible presence of gas. The probable hazard levels for drilling operations were determined. All the identified anomalies in the process of interpreting seismic sections were mapped to the geological hazards to select the optimal and safe installation point for drilling a prospecting or exploration well.
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Parks, Lisa. "Signals and oil." European Journal of Cultural Studies 12, no. 2 (May 2009): 137–56. http://dx.doi.org/10.1177/1367549409102421.
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This article examines the strategies of two satellite operators working across post-communist territories of Central Asia: Eutelsat and Kazsat. To do so it develops a critical approach called footprint analysis, which involves investigating the variety of practices that occur within range of a given satellite's service. Satellites have been used in post-communist territories to circulate broadcast and telecommunication signals, facilitate flows of capital and reshape geographic imaginaries. In addition, satellites have become orbital platforms for the Caspian's booming oil industry. Satellites are used to support everything from surveying oil fields to monitoring drilling operations, from construction of oil rigs to the maintenance of pipelines. The article sets out to develop a model of analysis which can account for the more 'cultural' uses of satellites (i.e. for broadcasting) in relation to their more 'extractive' uses (i.e. for natural resource development).
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Zhang, Ming Zhu, Yong Dai, and Bo Guo. "Development of a New Type of Hydraulic Drilling Car Used in Coal Mine." Key Engineering Materials 522 (August 2012): 556–59. http://dx.doi.org/10.4028/www.scientific.net/kem.522.556.
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Coal gas accident is the main threat to the safety production in coal mine,it needs a safe and efficient drilling equipment to detection and drainage in the gas area.At present,the equipments detect and drainage in underground coal mines are mainly fission rigs,which move time-consuming, and the efficiency of drilling is low.This paper introduces a new kind of full hydraulic drill car used in coal,it includes the integral design of the car, the structure layout, the drilling arm and the main parts of design ideas.The new drill carriage adopts the caterpillar vehicle structures,full hydraulic pressure drives,it can automatically change the drill rod, prevent bit-stuck device,can freely passage in the narrow roadway,arrived at the reservation of the drilling position and carries on the omni-directional drilling,it can meets various mine construction requirements, and it has a broad market prospect.
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Saigo, Hayato. "Category Algebras and States on Categories." Symmetry 13, no. 7 (June 29, 2021): 1172. http://dx.doi.org/10.3390/sym13071172.
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The purpose of this paper is to build a new bridge between category theory and a generalized probability theory known as noncommutative probability or quantum probability, which was originated as a mathematical framework for quantum theory, in terms of states as linear functional defined on category algebras. We clarify that category algebras can be considered to be generalized matrix algebras and that the notions of state on category as linear functional defined on category algebra turns out to be a conceptual generalization of probability measures on sets as discrete categories. Moreover, by establishing a generalization of famous GNS (Gelfand–Naimark–Segal) construction, we obtain a representation of category algebras of †-categories on certain generalized Hilbert spaces which we call semi-Hilbert modules over rigs. The concepts and results in the present paper will be useful for the studies of symmetry/asymmetry since categories are generalized groupoids, which themselves are generalized groups.
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Park, Kwang Soo, Sook Hwan Kim, and Dong Kyu Kim. "Study of Formability of Steel Thick Plates for Offshore Structures." Key Engineering Materials 622-623 (September 2014): 322–29. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.322.
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A jack-up rig or a self-elevating unit is a type of mobile platform that consists of a buoyant hull fitted with a number of movable legs, capable of raising its hull over the surface of the sea. The buoyant hull enables transportation of the unit and all attached machinery to a desired location. Once on location the hull is raised to the required elevation above the sea surface on its legs supported by the sea bed. The legs of such units may be designed to penetrate the sea bed, may be fitted with enlarged sections or footings, or may be attached to a bottom mat. Generally Jack up rigs are not self-propelled and rely on tugs or heavy lift shipsfor transportation. Formability problems in offshore structure construction where particularly high-strength steels are used for chords and racks. Attainment of mechanical properties is not usually difficult, although procedural trials are advisable. Fatigue cracking is probably the major cause of service failure of jack-up rigs, and the use of high-strength steels, which permits higher static stress limits, can exacerbate this problem. Roll forming process is one of the most widely used processes in the world for forming metals. It can manufacture goods of the uniform cross section throughout the continuous processing. However, process analysis is very difficult because of the inherent complexity. Therefore, it is time-consuming and much money is needed for manufacturing goods. In order to overcome this difficulty, a new computational method based on the rigid-plastic finite element method is developed for the analysis of roll forming process.
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Song, Yue, Nian-Zhong Chen, and Ningchuan Zhang. "Coupled motion characteristics of a large-scale tunnel element suspended by immersion rigs in the vicinity of seabed." Tunnelling and Underground Space Technology 110 (April 2021): 103804. http://dx.doi.org/10.1016/j.tust.2020.103804.
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Song, Yue, Nian-Zhong Chen, and Ningchuan Zhang. "Coupled motion characteristics of a large-scale tunnel element suspended by immersion rigs in the vicinity of seabed." Tunnelling and Underground Space Technology 110 (April 2021): 103804. http://dx.doi.org/10.1016/j.tust.2020.103804.
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Pao, William, Ban Sam, Mohammad Shakir Nasif, and Rohaizad B. M. Norpiah. "Numerical Validation of Two-Phase Slug Flow and its Liquid Holdup Correlation in Horizontal Pipeline." Key Engineering Materials 740 (June 2017): 173–82. http://dx.doi.org/10.4028/www.scientific.net/kem.740.173.
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The transition of one flow regime into another is a very common phenomena in pipeline networks, which can be potentially hazardous for the structural integrity of the pipeline. Literature review showed that there is almost no reported detail investigation of transitional flow whereby the fluid constituents change from one regime to another especially slug transition. Most of the open research papers focused on slug flow regime and its liquid holdup in horizontal pipelines and channels have been carried out on experimental test rigs. The objective of this study is to explore oil-gasoil vapor slug transition and its liquid holdup in a 3.15 inch diameter horizontal straight pipe. The abrupt change in gas/liquid velocities, which causes transition of flow patterns is analyzed using incompressible Volume of Fluid (VOF) method, along with Piecewise Linear Interface Construction (PLIC) technique to capture the sharp front of segregated gas-liquid interface. Slug liquid holdup derived from the present numerical model is compared to existing experimental correlations in the literature.
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Horsewell, A., C. C. Appel, and J. B. Bilde-Sørensen. "“Leaky vacuum” SEM for materials scientists." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 846–47. http://dx.doi.org/10.1017/s0424820100166695.
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‘Leaky vacuum’ SEM is carried out at Risø using the Electroscan™ E-3 Environmental SEM and the low vacuum JEOL 5310 LVSEM. In our laboratory, a wide variety of materials problems has led us to develop several novel ‘leaky vacuum’ SEM methods which will be described here; a) in-situ fracture mechanics experiments, b) utilization of charge contrast to characterize local conductivity of insulators, c) removal of beam skirting error in energy dispersive X-ray analysis.In-situ fracture-mechanics experimentsCrack tip processes in non-conducting materials such as ceramics and polymer composites cannot be observed in the conventional SEM because the vacuum deposited conductive coatings peel away around the edges of the growing cracks. Charge prevention is readily achieved in die ESEM through ionization of the 5-10 torr atmosphere around the specimen surface. Not only is the large specimen chamber convenient for special rigs, but the poor vacuum means low demands on the rig construction with respect to out-gassing of lubricants, strain gauges and electrical monitors.
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Engelsen, Hilde, and Henrik Hannus. "Development of semi-submersible production vessels and its application to Australian waters." APPEA Journal 48, no. 1 (2008): 241. http://dx.doi.org/10.1071/aj07015.
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Semi-submersible platforms have a long history in the North Sea. In the beginning they were used mainly as mobile offshore drilling units, but in the last two decades the permanently moored semi-submersible production vessels have become widely used both as gas processing units and combination oil and gas production vessels. The design of production semi-submersibles evolved from that of drilling rigs, but there have since been significant improvements to the design of the hull and the topside configuration in relation to operational requirements and construction processes. The design methods have also been successfully adapted to areas with different environmental conditions, in combination with steel catenary risers and polyester mooring systems. On recent designs, simplifications of the hull systems are being implemented, which ease operation and enhance the passive safety. Finally, the semi-submersible production vessel’s application to Australian waters is discussed with focus on topside layout, hull design and mooring system design. Environmental conditions offshore northwest Australia are compared to North Sea and Gulf of Mexico conditions, along with vessel class and regulatory requirements.
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Thorhaug, Anitra. "Petroleum Industry's Use of Seagrass Restoration as Mitigation for Construction and as a Potential Cleanup Tool." International Oil Spill Conference Proceedings 2001, no. 1 (March 1, 2001): 385–89. http://dx.doi.org/10.7901/2169-3358-2001-1-385.
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ABSTRACT The Laguna Madre in Corpus Christi, Texas has a great deal of petroleum and natural gas activity while housing a national seashore. The area is a flyway for a wide array of bird species, as well as heavily fished. Historically, the laguna had a series of infrastructure modifications, gas and oil rigs, and real estate development. In the process of placing a drilling rig, a winter storm blew the vessel with the rig off a narrow channel. To remove the vessel, other vessels had to be called. A 35-acre accident occurred. In mitigation, 75 acres of the seagrass Halodule wrightii was planted in three areas: (1) a 15-acre dredge island where a portion of the island was scraped down from upland-spoil deposit to −2 ft mlw; (2) a mile-long channel where seagrasses were restored from −7 to 10 ft mlw to −3 to ft mlw; and (3) a persistently barren site for decades (scraped by another petroleum company's vessel) was restored in the shallows while holes were filled in and seagrass planted on top. The fill throughout was from the scraping from the dredge islands. The fill was transmitted several miles by a new device. Planting of Halodule plugs proceeded from March to July 1999. Within 3 months, the shallow sites had been covered with the restored Halodule,. Endangered species of roseate spoonbills, brown pelicans, great white herons and other wading and fishing birds were regularly feeding at two sites. The deeper sites had heavy fish populations return to the area, fished by man, seagulls and pelicans. Despite a direct hit by Hurricane Bret in 1999, lateral growth at all depths was deemed governmentally satisfactory. This same procedure with seagrasses is recommended for after-effects of estuarine oil spill cleanup, and mitigation banks of seagrasses are recommended for construction or operations mitigation.
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Matuszewski, Leszek, and Zbigniew Szydło. "The application of magnetic fluids in sealing nodes designed for operation in difficult conditions and in machines used in sea environment." Polish Maritime Research 15, no. 3 (October 1, 2008): 49–58. http://dx.doi.org/10.2478/v10012-007-0083-0.
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The application of magnetic fluids in sealing nodes designed for operation in difficult conditions and in machines used in sea environment Presented in article MF seals are being researched for sea technology purposes due to their excellent tightness and low resistance of motion. These features are most valuable for ring propellers and ship's main propeller shaft. There are more reasons why technologists payf significant attention for various MF seals applications in their difficult operating conditions. For instance, an advanced pumping systems are designed with contactless (screw or centrifugal) fluid seal used as the first stage seal and then the MF seal as the main seal. Further parts of the article contain discuss of the properties of magnetic fluids in the construction of MF seals. Sample of the few systems of magnetic fluid seals are presented, which have been researched lately in our laboratory including sea conditions. The magnetic fluids used in our seals are colloidal suspensions of magnetic nanoparticles. Undertaken earlier various systems selection for sea-water purposes forced us to focus on double sealing systems, in which the MF seal is used as the second seal following a conventional system especially adapted to co-operation with MF systems. This solution successfully limits direct contact of the sealed liquid with the magnetic fluid, and the entire sealing construction secures absolute tightness of the system. Using this solution we also can reduce costs by elements high accuracy avoidance. Research and design activities are carried out in the AGH Laboratory of Seals and Magnetic Fluid Applications together with Deep Water Department of Technical University of Gdansk over the use of magnetic fluid seals in sea water environment. These activities are oriented on working out MF seals able to work effectively in machines in which low-pressure water flow takes place. The objects of experimental investigations are seals having two different nominal diameters: 50 mm and 220 mm and two research rigs of different construction had to be built up. Works are scheduled to be continued.
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Aliyeva, Sevda, Javida Damirova, and Sevinc Abasova. "Research of the problem of optimization and development of a calculation method for two-stage chain drives used in heavy industrial vehicles in conditions of economic efficiency." EUREKA: Physics and Engineering, no. 4 (July 23, 2021): 105–12. http://dx.doi.org/10.21303/2461-4262.2021.001930.
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The article is dedicated to the problem of optimization of chain drives of the drilling unit. At present, increasing the power per machine to the optimal limits, reducing the material and energy consumption per unit capacity of the machine, as well as operating costs are considered topical issues. The machines that are designed and constructed to optimal limits must be very powerful and productive. The machines that are applied to perform drilling works in the oil and gas industry must be easy to operate, reliable and have ability to operate for a long time. When constructing such machines, their being lightweight, economical, as well as their preparation in a short time and at low cost should be taken into account in advance. In order to ensure the reliable operation of drilling rigs, it is more expedient to apply chain drive in their mechanical transmission. First of all, the application of chain drive in drilling units and hoisting mechanisms is considered. Then a calculation method was developed for the chain drives of the drilling unit used in deep exploration wells and the exploitation of wells, and, accordingly, the calculation of the chain drive was carried out. The chain drive consists of drive and driven sprockets and a chain that encompasses the sprockets and engages in their teeth. Chain drives with several driven sprockets are also used. In addition to the basic listed elements, chain drives include tensioners, lubricating device and guards. The chain consists of hinged links that provide mobility or “flexibility” of the chain. Chain drives can be performed in a wide range of parameters. The calculation took into account the quality of the material, the service life and durability of the chain drive construction
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MacLean, Ken. "Unbuilt Anxieties: Infrastructure Projects, Transnational Conflict in the South China/East Sea, and Vietnamese Statehood." TRaNS: Trans -Regional and -National Studies of Southeast Asia 4, no. 2 (June 7, 2016): 365–85. http://dx.doi.org/10.1017/trn.2016.3.
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AbstractThe conflicts shaping territorial claims and counter-claims to overlapping areas of the South China Sea threatens to significantly damage Sino-Vietnamese relations, destabilize regional security arrangements, and alter the geopolitical status quo. The governments of both countries routinely invoke historical documents, commission scientific studies, and cite legal principles to justify their competing claims in the maritime region and the resources contained therein. The role different types of energy infrastructure play in the state-level disputes have received little attention, however. This essay addresses this oversight. In it, I foreground the complex ways not yet built infrastructure affect Sino-Vietnamese relations as well as our theoretical understanding of “the state”, especially with regard to Vietnam. Not yet built infrastructure refers to more than the assemblage of things that will be built in the future to power the economy, such as oil rigs, natural gas pipelines, and refineries. The concept also includes the ideological positions that presuppose the materialization of blueprint plans in physical form, i.e., the broader goals such infrastructure is meant to achieve. Towards this end, the article focuses on how state actors and their proxies conceptualize the likely impacts not yet built infrastructure will have upon their respective interests once construction is completed. The case study highlights how the need for energy security strengthens national security at some moments, weakens it at others, and both at still others.
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Yang, Zhichao, Dung H. Duong, Willy Susilo, Guomin Yang, Chao Li, and Rongmao Chen. "Hierarchical Identity-Based Signature in Polynomial Rings." Computer Journal 63, no. 10 (April 28, 2020): 1490–99. http://dx.doi.org/10.1093/comjnl/bxaa033.
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Abstract Hierarchical identity-based signature (HIBS) plays a core role in a large community as it significantly reduces the workload of the root private key generator. To make HIBS still available and secure in post-quantum era, constructing lattice-based schemes is a promising option. In this paper, we present an efficient HIBS scheme in polynomial rings. Although there are many lattice-based signatures proposed in recent years, to the best of our knowledge, our HIBS scheme is the first ring-based construction. In the center of our construction are two new algorithms to extend lattice trapdoors to higher dimensions, which are non-trivial and of independent interest. With these techniques, the security of the new scheme can be proved, assuming the hardness of the Ring-SIS problem. Since operations in the ring setting are much faster than those over integers and the new construction is the first ring-base HIBS scheme, our scheme is more efficient and practical in terms of computation and storage cost when comparing to the previous constructions.
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Feder, Judy. "Implementation of an Intelligent Drilling Automation System in the Middle East." Journal of Petroleum Technology 73, no. 02 (February 1, 2021): 45–46. http://dx.doi.org/10.2118/0221-0045-jpt.
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This article, written by JPT Technology Editor Judy Feder, contains highlights of paper SPE 203251, “Drilling in the Digital Age: Harnessing Intelligent Automation To Deliver Superior Well-Construction Performance in a Major Middle Eastern Gas Field,” by Brennan Goodkey, Gerardo Hernandez, and Andres Nunez, Schlumberger, et al., prepared for the 2020 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, held virtually from 9-12 November. The paper has not been peer reviewed. While breakthroughs in digital technology have rewarded many industries with a step change in productivity and efficiency during the past decade, the drilling industry has yet to benefit on a large scale from these advances. The complete paper details the introduction of a drilling automation system (DAS) to deliver superior well-construction performance in a major gas field in the Middle East. The DAS was deployed on two onshore gas drilling rigs. The paper discusses the technology itself, the deployment process, implementation challenges, the agile development model, and the results achieved. Introduction In 2018, Schlumberger partnered with a major Middle Eastern national oil company on one of the world’s largest lump-sum, turnkey gas-well-delivery projects, where drilling operations had already been optimized by targeting high-impact, low-effort areas of opportunity. Drilling automation was pursued to achieve an improvement in performance, specifically to shift the technical limit and to minimize the frequency of service incidents that could cost days of nonproductive time (NPT). An in-house solution under development for some time was designed to take control of the rig’s surface equipment to automate and optimize most drilling tasks and to generate value in the following areas: Automation of drilling actions to perform exactly as planned, within the safe limits of operation, by eliminating the inconsistency of manual operation and its susceptibility to human factors Identification and mitigation of drilling dysfunctions that could lead to costly tool failures and incidents by using intelligence engines that would adapt drilling parameters continuously for best performance Technology Overview The DAS was developed as the execution component of a well-construction platform designed to link planning and execution. The planning component allowed for all well-design stakeholders to collaborate online and create the well plan simultaneously. Once prepared, the plan would be exported to the rig as a machine-interpretable digital drilling plan that the DAS could digest. With the validation of rig personnel, the DAS would then take control of a selection of drilling actions and execute exactly as instructed in the well plan. While drilling, extensive information would be collected to serve as a vehicle to drive performance when planning future wells. In the deployment summarized in the complete paper, a pilot version of the drilling automation module was deployed as a standalone product. The key objectives of design included three categories - dynamic planning, safety and resilience, and interoperability.
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Stanciu, Lavinia Silvia, and Ioan Popa. "Stress and Displacements Analysis for Drilling Mast Elements Made of Rectangular Pipe under the Action of the Wind as a Hurricane." Key Engineering Materials 601 (March 2014): 116–19. http://dx.doi.org/10.4028/www.scientific.net/kem.601.116.
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According to API 4F, SR EN ISO 14693:2004, the action of wind as a hurricane, with a speed of 120 km/h, represents a special load the drilling masts, which are a part of the drilling rigs, are submitted to. By their construction, the masts are multiple statically indetermined structures, made of many welded ends beams, and are designed as a component of the hoisting system, having some main purposes as supporting devices as the crown block at the top, the crane, the rotary swivel etc and providing support for the drill pipes to be stacked vertically during the round trips operations. In the present paper was analyzed, from this point of view, a drilling mast made of rectangular pipes, rated for a maximum hook load of 300 kN. The authors calculated the wind pressures, in accordance with the formulae specified in the standards, and introduced this special loading as a distributed load, firstly on the transversal direction of the mast and then on the longitudinal direction, with respect to the spatial reference system attached to the analyzed mast. Using the Finite Element Method, the nodes displacements and mast`s elements stress were determined. The most important obtained values of the displacements and stress were graphically shown and commented and, also, interesting conclusions are presented concerning the drilling mast resistance in specific conditions that occur in case of the wind action as a hurricane.
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Wright, D. J., and S. R. le Poidevin. "DEVELOPMENT OPTIONS FOR OFFSHORE OIL AND GAS FIELDS: IMPLICATIONS FOR OPTIMUM LONG-TERM RECOVERY." APPEA Journal 32, no. 1 (1992): 391. http://dx.doi.org/10.1071/aj91030.
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Technology used in the Australian offshore oil and gas industry in recent years has diversified with the introduction of innovative concepts for field developments. These innovations are aimed at cost reduction and greater access to reserves, especially those in small and remote fields. Further innovations are anticipated as research progresses in several areas of potential cost reduction. Changes in technology can dramatically affect the relative economics of data acquisition, contingency planning and the extent of field development. Drilling and workover economics, well servicing, reservoir surveillance and the opportunities for infrastructure development are strongly dependent on the choice of development technology. These choices, in turn, have implications for long-term recovery, including the discovery and development of new pools and extensions to known pools, overall field recovery factors, the opportunities for development of gas caps and nearby fields, and the future potential for enhanced oil recovery (EOR).Government involvement in development approvals in various countries has diverse objectives. The Australian Petroleum (Submerged Lands) Act specifies as one objective the optimum long-term recovery of petroleum. Critical areas of interest are pre-development planning with necessarily incomplete information, the phenomenon of unexpected reserves growth, and provision for contingencies such as well failures. Early drilling and completion decisions and infrastructure planning have major effects on future developments. Subjects of direct relevance for future improvements in development economics include reductions in pipeline construction costs, reductions in the cost of drilling from mobile rigs and flexibility in completion design.
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Mironiuk, Waldemar. "Model studies of ships as an element of maritime transport." WUT Journal of Transportation Engineering 121 (June 1, 2018): 267–76. http://dx.doi.org/10.5604/01.3001.0014.4607.
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Transport of large amounts of cargo, mining and exploiting natural mineral resources, carrying large number of passengers by sea are characterized by high risk, even if the latest technologies are employed. It is not a long time ago that thousands of people lost their lives in catastrophes of ships, off-shore oil rigs and other marine objects. It is estimated that around 80% of accidents at sea are caused by making wrong decisions by persons keeping watch on the bridge, especially during difficult navigational and weather conditions. Accidents can also be caused by lack of skills necessary for crews or absence of appropriate tools. Therefore, it is important that seafarers should be trained in accordance with the highest standards. The scope of crew research and training may include both static, dynamic and damage stability. This stand bad also enables the analysis of the influence of the free surface effect of the liquid occurring in the compartments or tanks after damage to the ship's hull and the analysis of the impact of cargo operation on the ship's initial stability. Experiences gained on the research stand lead to a better understanding of the phenomena occurring in the current operation of the ship and to improve the safety of swimming. The aim of this article is presentation selected scenarios for the model tests of vessels and to familiarize with the construction of selected types of ship models and the capabilities of stability test stands in the aspect of improving the safety at sea.
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van Og, Geertjan, and Jeroen Burgerhout. "Advanced directional CwD system pushes integration envelope to elevate efficiencies and reduce costs." APPEA Journal 57, no. 2 (2017): 676. http://dx.doi.org/10.1071/aj16084.
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The evolution of casing while drilling (CwD) illustrates the economic, efficiency and health, safety and environment benefits achievable with the seamless integration of downhole tools and surface drilling equipment. However, several technology gaps have restricted CwD from reaching its full potential to optimise the well construction process. This paper describes the integrated development and application of a retrievable Enhanced Casing Installation (ECI) system, engineered to take directional (Level 3) casing drilling technology to another level and further expand the functionality of both specialised and standard land drilling rigs. The system, which enables directional drilling with composite casing and standard mud motors, differs from typical Level 3 CwD methodologies in that the composite option allows bottom hole assembly (BHA) placement inside the shoetrack, thus helping reduce vibrations and wear on the reamer and other downhole tools. Along with increased well stability and allowing simultaneous logging/measuring while drilling, the ECI device is configured with a comparably lightweight BHA, requiring fewer components, such as jars and roller reamers, making it easily retrievable with cable. As discussed, the cost-effective integration of downhole and surface equipment is clearly reflected in the capacity to rerun the retrieved bit and reamer – a marked difference between the sacrificial bits required for the commonly used Level 2 (vertical) CwD technique. Moreover, the authors will present results of a specialised test stand evaluation and subsequent field trial, where the system was integrated on a fit-for-purpose rig and used for casing drilling at a 45° angle with the BHA pulled intact from 1800 m MD.
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Alexey, Neroslov. "The Method of Cluster Drilling in the Western Ural as the Beginning of the Technical and Economic Revolution in the World Drilling." TECHNOLOGOS, no. 3 (2020): 47–57. http://dx.doi.org/10.15593/perm.kipf/2020.3.03.
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In 1943, at the height of the Great Patriotic War, the new revolutionary drilling technique with high efficiency was used in Krasnokamsk oilfield of Molotov (Perm) Oblast for the first time in the world – the cluster turbodrilling method. The development of oil industry in Prikamye in the 1940s was associated with certain complications. The main deposits of the Krasnokasmk oilfield discovered before the war turned out to be located due to a number of reasons within the area of industrial and residential construction of the city of Krasnokamsk and under the Kama river and the Paltinskoye swamp close to the city. Conventional drilling methods could not be used for their development. The way out was to use the method of directional drilling that was little known at that moment. The development of the innovative technology in Krasnokamsk oilfield in 1942 was largely due to the involvement of the specialists of the Experimental Turbodrilling Bureau evacuated from Baku. Directional drilling which involved the deviation of the bottom hole (the ultimate lowest point of the well) from the wellhead (the initial uppermost location) by several hundred metres opened up broad opportunities for developing hard-to-recover oil deposits while significantly accelerating and ensuring cost savings of the drilling process. The directional drilling served as the basis for the development in Prikamye of an advanced technology of cluster drilling when several directional wells with different azimuths were drilled from a small well pad. In 1943–1944, cluster drilling was tested and successfully used in Krasnokamsk oilfield. The cluster drilling comprised an entire range of innovative solutions including the movement of assembled drilling rigs without dismantling power equipment. Also, it resulted in the reduction of total labour costs, scope of construction and assembly works, costs of building oilfield roads, power lines and pipelines, and transportation costs. People’s Commissariat of Oil Industry of the USSR initiated a large-scale rollout of the advanced method of cluster drilling in the largest oil-producing regions of the Soviet Union – Azerbaijan and the North Caucasus, and the area of the “second Baku” – Bashkiria, Tatary, and Kuybyshev oblast. The transition to the advanced and cost-saving technology of cluster drilling laid the foundation for the technical and economic revolution of the world drilling practices.
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Wang, Xiao, Dacheng Cong, Zhidong Yang, Shengjie Xu, and Junwei Han. "Iterative learning control with complex conjugate gradient optimization algorithm for multiaxial road durability test rig." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 7 (July 17, 2018): 2349–60. http://dx.doi.org/10.1177/0954406218786981.
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Service load replication performed on multiaxial hydraulic test rigs has been widely applied in automotive engineering for durability testing in laboratory. The frequency-domain off-line iterative learning control is used to generate the desired drive file, i.e. the input signals which drive the actuators of the test rig. During the iterations an experimentally identified linear frequency-domain system model is used. As the durability test rig and the specimen under test have a strong nonlinear behavior, a large number of iterations are needed to generate the drive file. This process will cause premature deterioration to the specimen unavoidably. In order to accelerate drive file construction, a method embedding complex conjugate gradient algorithm into the conventional off-line iterative learning control is proposed to reproduce the loading conditions. The basic principle and monotone convergence of the method is presented. The drive signal is updated according to the complex conjugate gradient and the optimal learning gain. An optimal learning gain can be obtained by an estimate loop. Finally, simulations are carried out based on the identified parameter model of a real spindle-coupled multiaxial test rig. With real-life spindle forces from the wheel force transducer in the proving ground test to be replicated, the simulation results indicate that the proposed conventional off-line iterative learning control with complex conjugate gradient algorithm allows generation of drive file more rapidly and precisely compared with the state-of-the-art off-line iterative learning control. Few have been done about the proposed method before. The new method is not limited to the durability testing and can be extended to other systems where repetitive tracking task is required.
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Trlifaj, Jan. "Constructions and homological properties of simple von Neumann regular rings." Czechoslovak Mathematical Journal 40, no. 4 (1990): 583–91. http://dx.doi.org/10.21136/cmj.1990.102412.
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Weatherl, Michael H. "Technology Focus: Drilling Automation and Innovation (February 2021)." Journal of Petroleum Technology 73, no. 02 (February 1, 2021): 44. http://dx.doi.org/10.2118/0221-0044-jpt.
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Drilling automation and innovation continue as dominant trends despite market downturns and unprecedented challenges in the past year. In many ways, the drive toward new efficiencies and step changes in well-construction performance has taken on an even greater sense of urgency. Further advancements in automation and innovation in well construction are recognized globally as keys to unlocking new opportunities in the ever-changing world in which we live. OTC Live sessions in late 2020 included a fascinating session titled “Opportunities and Challenges in Frontier Basins and Emerging Offshore Areas.” Despite pandemic-induced uncertainty, a significant number of high-impact exploration efforts, including projects in deepwater Gulf of Mexico, Brazil, west Africa, the Mediterranean, and Asia were ongoing. Panelists agreed, given world population and energy consumption being forecast to grow 20% by 2040, that increased hydrocarbon supplies, in addition to renewables, are essential to meeting future demand. The discussion also highlighted increased emphasis on carbon footprint reduction. Leaders from Shell, Expro, Wood Mackenzie, and others spoke to a CO2-intensity/barrel of oil equivalent chart comparing relative values for deep water, unconventionals, oil sands, and liquefied natural gas. It is noteworthy that deepwater production represents the lowest carbon footprint of all hydrocarbon sources by a significant margin. This advantage, combined with the potential for large resource size, high flow rates, and low well count, suggest that deepwater assets will compete in long-term portfolios for many operators. Referring to the current selection of SPE drilling-related manuscripts, automation of land rigs within onshore unconventional basins remains a widely published subject. More specifically, automation of the directional drilling process continues to yield improvements in performance and efficiency. It is often noted that well costs have been reduced by more than 50% with advancements related to horizontal technology, digitalization of well construction, and rig automation. These technologies were largely initiated within onshore, unconventional projects, but application is now wide-spread for offshore, complex wells. Selected papers in this feature are chosen to highlight the latest achievements and near-term opportunities across the full spectrum of upstream projects. A consistent message from paper SPE 203251 regarding drilling automation in the digital age reads, “industry has yet to benefit on a large scale from these advancements and…significant value remains untapped.” This reoccurring theme appears across operator and geographical boundaries, revealing significant opportunity and the need for ongoing emphasis. Software and hardware evolution progresses along with more- comprehensive integration of rig equipment and functionality. Industry now is more focused on moving from automation of individual tasks toward automation of the full well-construction process from plan to completed borehole. This idea is presented in paper SPE 201763. Change management remains a key issue within the process to ensure adequate control, early buy-in from stakeholders, and strong leadership. In summary, impressive examples of ongoing innovation span domestic unconventional plays, remote/international locations, geologically complex thrustbelt fields, and deep water with managed-pressure drilling in narrow pore pressure/fracture gradient environments. The few selections that appear here are a reflection of many more published by SPE in the past year and are a powerful testament to the ingenuity and perseverance of those involved.
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CRIST, RANDALL, and JOHN N. MORDESON. "VAGUE RINGS." New Mathematics and Natural Computation 01, no. 02 (July 2005): 213–28. http://dx.doi.org/10.1142/s1793005705000123.
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We examine the notion of a vague ring. We develop a method of constructing vague rings which can be used in the construction of other algebraic structures. We make a connection between vague rings and M-adic topologies on rings and also to the solution of nonlinear systems of equations and to the convergence of Cauchy sequences in power series rings. We introduce the notion of Ω-vagueness which we apply to the integration and differentiation of fuzzy functions.
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Jézéquel, Ronan, Karine Duboscq, Léa Sylvi, Emma Michaud, Lise Millera Ferriz, Enora Roic, Robert Duran, et al. "Assessment of oil weathering and impact in mangrove ecosystem: PRISME Experiment." International Oil Spill Conference Proceedings 2017, no. 1 (May 1, 2017): 634–56. http://dx.doi.org/10.7901/2169-3358-2017.1.634.
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Abstract 2017-410 Mangroves are among the most sensitive marine ecosystems to oil pollution due both to the sensitivity of mangroves species and to the high persistence of hydrocarbons in these environments. Despite their ecological and socio-economic value, the potential effects of an oil spill on French Guiana mangroves remain so far unknown. Yet, there is an increasing transboundary risk of oil spill due to Brazilian offshore oil exploitation (in mid-April 2013, there were 122 offshore drilling rigs in Brazil, including 29 under construction – Brazilian Amapá region located in the French Guiana border area is thought to become an important world oil production area in the coming years). The aim of the PRISME project was to assess the natural degradation of oil in mangrove sediment as well as its impact on benthic communities (micro, meio and macrobenthos): a one-month in situ experiment was conducted in the young French Guianese mangrove (around 3 years old) at the mouth of the Sinnamary estuary. The experimental units consisted in eight plastic cores (Ø : 10 cm ; height: 30 cm) manually introduced within sediments. A thin layer of oiled sediment (2 cm, 20 000 ppm) was applied on four cores while the remaining four cores were considered as control (no oil addition). Three cores were additionally sampled at the beginning of the experiment as initial control sediments. After one month in situ, the eight cores were collected and sliced on site into different sedimentary layers aliquots for later analyses (hydrocarbons, bacterial, meio, macrofauna fauna diversity, bioturbation, biogeochemical parameters). Samples were sent to the different laboratories involved in this multidisciplinary project. Results and knowledge gained from this experimental work were used to develop an approach for assessing coastal vulnerability for oil spills preparedness in mangroves.
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Melnyk, О. "ORGANISATION OF THE TRANSPORTATION PROCESS OF OVERSIZED CARGO BY MODES OF TRANSPORT. ROLE AND POSITION OF MARITIME TRANSPORT IN THIS PROCESS." Municipal economy of cities 1, no. 154 (April 3, 2020): 231–39. http://dx.doi.org/10.33042/2522-1809-2020-1-154-231-239.
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The article deals with comparison of modes of transportation concerning oversized and heavylift cargo carriage. The peculiarities of each mode of transport directed to determine the rational spheres of its use, but at the same time the development of the geography of maritime trade and intercontinental mainline freight flows has had a significant impact on the increase in the volume of transportation of industrial cargoes, raw materials and high-tech equipment and served as an impetus for the realization of the competitive advantages of the water transport over the other modes of transportation. Assistance in the development of external economic relations and provision of international trade relations as priority components in the list of advantages of which marine transport has in the world economy. Therefore, it becomes obvious that one of the most difficult types of transportation is the carriage of oversized and heavylift cargoes. It is reasonable to note that this concept has differences depending on the type of transport used. There are also various rules of transportation by rail, sea, air and road. Advantages and disadvantages of the implementation of the transportation process of oversized cargo using a particular mode of transport are not very apparent and depend primarily on factors such as indication of dimensions, information on weight, type of cargo, route requirements and time required for transportation, volume of transportation, specific conditions and requirements for carriage. Oversized cargoes in their turn include the cargo units of construction vehicles (excavators, bulldozers, graders, trucks), drilling rigs, earthmoving machines, various machinery and mechanisms for mining industry, steel structures and bridge supports, wind generators, transformers, as well as extra-length equipment, parts and components of plants. Keywords: Oversized and heavylift cargo transportation, water transport, mode of transportation
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Bills, Kym. "Building a world-class Australian decommissioning industry." APPEA Journal 58, no. 2 (2018): 690. http://dx.doi.org/10.1071/aj17154.
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Collaboration in decommissioning offshore infrastructure could save both industry and taxpayers billions of dollars and facilitate new industries and exports for Australia, especially in the Asia-Pacific region. At the end of the liquefied natural gas (LNG) plant construction boom, Australia must not miss out on this major new opportunity. The 2017 bid for Commonwealth funding to establish a Decommissioning Offshore Infrastructure Cooperative Research Centre (DOI-CRC) involved more than 30 participants and many other collaborators. High-level commitments were made by Chevron, Woodside, Shell, BHP, ExxonMobil, Quadrant, The University of Western Australia, Curtin University, the University of New South Wales, Deakin University, Australian Maritime College, CSIRO and Australian Institute of Marine Science. A Perth-based DOI-CRC was supported by National Energy Resources Australia, National Offshore Petroleum Safety and Environmental Management Authority and other Australian Government bodies and by the Western Australian Government and its Chief Scientist and agencies but did not receive sufficient support from the CRC Advisory Committee. Meeting decommissioning challenges in the North West Shelf, Bass Strait and the Northern Territory in a timely, robust, scientific, efficient and cost-effective manner that contributes to a sustainable marine environment should draw upon and augment international best practice with local capability and expertise. Good science and innovative engineering are needed to support regulatory approval of options such as ‘rigs to reefs’ and commercial opportunities such as in waste management and expanded fishing and tourism. APPEA and operators wish to maintain DOI-CRC’s momentum and learn from UK research arrangements through funding marine science projects. But we must be much broader if we are to build a sustainable world-class Australian decommissioning industry. In particular, we need to work more closely with state and federal regulators and policymakers and undertake more engineering science research and innovation.
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SHAH, TARIQ, and ANTONIO APARECIDO DE ANDRADE. "CYCLIC CODES THROUGH B[X], $B[X;\frac{1}{kp}Z_{0}]$ AND $B[X;\frac{1}{p^{k}}Z_{0}]$: A COMPARISON." Journal of Algebra and Its Applications 11, no. 04 (July 31, 2012): 1250078. http://dx.doi.org/10.1142/s0219498812500788.
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It is very well known that algebraic structures have valuable applications in the theory of error-correcting codes. Blake [Codes over certain rings, Inform. and Control 20 (1972) 396–404] has constructed cyclic codes over ℤm and in [Codes over integer residue rings, Inform. and Control 29 (1975), 295–300] derived parity check-matrices for these codes. In [Linear codes over finite rings, Tend. Math. Appl. Comput. 6(2) (2005) 207–217]. Andrade and Palazzo present a construction technique of cyclic, BCH, alternant, Goppa and Srivastava codes over a local finite ring B. However, in [Encoding through generalized polynomial codes, Comput. Appl. Math. 30(2) (2011) 1–18] and [Constructions of codes through semigroup ring [Formula: see text] and encoding, Comput. Math. Appl. 62 (2011) 1645–1654], Shah et al. extend this technique of constructing linear codes over a finite local ring B via monoid rings [Formula: see text], where p = 2 and k = 1, 2, respectively, instead of the polynomial ring B[X]. In this paper, we construct these codes through the monoid ring [Formula: see text], where p = 2 and k = 1, 2, 3. Moreover, we also strengthen and generalize the results of [Encoding through generalized polynomial codes, Comput. Appl. Math.30(2) (2011) 1–18] and [Constructions of codes through semigroup ring [Formula: see text]] and [Encoding, Comput. Math. Appl.62 (2011) 1645–1654] to the case of k = 3.
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ABRAMS, GENE, and P. N. ÁNH. "SOME ULTRAMATRICIAL ALGEBRAS WHICH ARISE AS INTERSECTIONS OF LEAVITT ALGEBRAS." Journal of Algebra and Its Applications 01, no. 04 (December 2002): 357–63. http://dx.doi.org/10.1142/s0219498802000227.
Full textAbstract:
Two known constructions of rings R, each having the property that different sized matrix rings Mn(R) and Mm(R) are isomorphic but the free left R-modules RRn and RRm are not, are shown to be isomorphic. The first construction utilizes a direct limit, while the second involves an intersection process.