bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of stress distribution simulation under fracture in predicting drilling leakage in Bozhong area
Authors: Xu Sheng-Li , Li Hui , Sun Yu-Hong , Zhang Ye , He Shuang-Cheng , Wang Bin 
Published: November 2024

Abstract
Faults and fractures are the most important factors that cause serious drilling leakage. Aiming to meet the production demand of improving the the reliability of leakage prediction, this paper uses the forward modeling technique of stress distribution in fault zones, by forward modeling of different fault combination modes, different scale fault stress influence ranges, and different fault zone filling modes, the stress changes, sizes, distribution characteristics, impact ranges, and properties of the fault zones on both sides of the fault were quantitatively displayed, achieving a comprehensive and quantitative characterization of the stress distribution under the fault; In addition, under the guidance of stress distribution, the reliability of leakage prediction can be improved effectively; Farther more, this paper combined the characteristics of the well-seismic data in the actual fault zone with the distribution of drilling leakage, proves that the three-dimensional space stress simulation and the stress intensity can effectively predict the plane and longitudinal distribution position of drilling leakage. The practicability of the method has been effectively applied and tested in the drilling leakage prediction and tracking in Bozhong area.
Development Characteristics of Single Sand Body of Yan’An Formation in Western Ordos Basin
Authors: Hui Fang , Zhang Tong , Wang Kunpeng , Sun Wei , Wang Bo 
Published: November 2024

Abstract
The precise characterization of the types and spatial distribution of strongly heterogeneous single sand bodies are a necessary prerequisite for the study of oil and gas reservoir formation. This article takes the Yan’an Formation in the western Ordos Basin as an example to systematically study the internal structure and profile distribution of strongly heterogeneous single sand bodies. The research results indicate that using mud interlayers, physical interlayers, and calcium interlayers as layered interfaces can effectively classify the single sand body types of each small layer in the Yan’an Formation. The drilling rate of a single sand body is between 50% and 85%, and the average number of sand layers is between 3 and 8. When two rivers intersect and are horizontally tangent, due to the mutual erosion of water flow, relatively thick sand bodies can be retained, ultimately resulting in a pattern of relatively thick on both sides and thin in the middle. The single sand body at the bottom is the most developed and has good continuity. In the transverse direction of the river, the continuity of a single sand body is relatively poor, and the extension range of a single sand body is 300m to 1200m. Along the river channel, single sand bodies are developed with good continuity, extending about 2km. The connectivity between the sand body and the well varies with the migration of the river in the transverse river profile of the research area. The lateral contact relationship of a single sand body determines the boundary of the river channel, and the profile characteristics of a single sand body also reflect its planar distribution. The intergranular pores of the Yan’an Formation sand body are relatively developed, and a large number of quartz particles offset the compressive stress of the rock. The corrosion of feldspar particles is relatively strong, retaining a large number of primary intergranular pores. There is a good quantitative relationship between the thickness of sand in a single level channel and the width of the channel. The control of the well network on the sand body is relatively small, and there is room for further densification of drilling. The vertical contact relationship of a single sand body in the Yan’an Formation of the research area can be divided into three modes: separation, stacking, and overlapping. Cut pile sand bodies with good connectivity have good production capacity. The different planar contact relationships reflect the degree of connectivity between channel sand bodies and wells, with lateral cutting type>docking type>isolation type. The side cut sand body has uniform longitudinal water absorption, small water absorption difference, and high-water drive degree. The isolation type has the greatest difference in water absorption rate and the lowest degree of water flooding.
Numerical Investigation on Cathodic Protection of X80 Pipeline Steel in Marine Environment
Authors: Wang Shuli , Yao Jing , Hao Chengming , Xiang Xiaosen , Chen YiLin , Rao Yongchao 
Published: November 2024

Abstract
Submarine pipelines are usually buried in sea mud, but part of the pipes will be exposed to seawater directly because of the change of seabed, the differences between sea mud and seawater result in different corrosion states. Generally, due to its large geometric size, complex medium, difficult to detect and other reasons, corrosion defects will cause greater harm to pipeline materials. A numerical analysis model of the outer surface corrosion of submarine pipelines was developed to simulate status of cathodic protection, furthermore, potential distribution and local density of current inside the defects was also analyzed and evaluated. The results indicates that:
(1)The CP potential distributes more evenly in sea mud when the same sacrificial anode is used, and the cathodic protection current density needed to meet the anti-corrosion requirements is much larger in seawater than in sea mud.(2)Compared with sea mud, the polarization potential of the sacrificial anode in seawater is more negative, and the CP potential at the edge of anodes is the most positive in both sea mud and seawater. Furthermore, in seawater, the dissolution rate of sacrificial anodes closer to the seabed is lower, and anodes dissolve much faster at the inner surface, while it is just the opposite in sea mud.(3)Cathodic protection cannot ensure complete and effective protection at defect points. At defect bottom, the cathodic protection current is partially shielded, reducing the effectiveness of CP system on corrosion protection of pipelines. Moreover, the shielding effect of defect point on cathodic protection current has a great deal with the geometric shape of defect points, with decreasing width and increasing depth, the shielding phenomenon becomes more obvious.(4) Numerical simulation technique based on the finite element model provides a new method to solve this problem and plays a positive role in assessing anti-corrosion status and the service life of anodes.
Research on the Mechanism of Nanoparticle materials in Oil Displacement and its Application
Authors: Zhang Yiran , Ma Yishu , Ju Binshan , Li Lingyun 
Published: November 2024

Abstract
The application of nanoparticles in the field for enhanced oil recovery (EOR) is a new technology, which has attracted widespread concern. However, there is a lack of systematic research on the types and mechanisms. In order to clarify the types and characteristics of the material, oil displacement mechanism and its effect on oil and water flow, this paper systematically sorted out the classification of nanoparticle materials used in the field of petroleum development, and analysed its percolation and oil displacement mechanism. Numerical simulation and field data analysis were carried out to study the applications of two types of nanomaterials in improving reservoir water injection and oil displacement efficiency quantitatively. The results show that the main mechanism of nanoparticle flooding is to change reservoir wettability, reduce oil-water interfacial tension, modify the mobility ratio between water and oil phases, and reduce asphaltene precipitation. Lipophilic and hydrophobic nanoparticle may reduce injection pressure, and increases significantly injection in low permeability reservoirs, and the average water injectability of 6 wells is increased by 177.76%. The displacement efficiency of hydrophilic and oleophobic nanoparticles can be increased by 14.78%. This paper reveals the oil displacement mechanism of nanoparticle materials and establishes a new method to quantitatively predict the oil displacement effect of nanoparticle materials, which provides a basis and reference for the application of oilfield.
Application of Microwave Imaging Combined with Electromagnetic & Ray Localization in Pipeline Deformation Detection
Authors: Huang Hai , Dai Zhixiang , Tang Ping 
Published: November 2024

Abstract
This article aims to explore a new type of non excavation pipeline detection method, which combines microwave imaging with electromagnetic and ray positioning methods, to improve the accuracy and efficiency of pipeline detection and accurately locate the deformation of pipelines. [Method]Firstly, the microwave imaging method is used to detect the pipeline, and the deformation of the pipeline is determined by the reflection of the microwave. At the same time, electromagnetic and X-ray positioning technologies are used to accurately locate the pipeline and its deformation situation, in order to more accurately understand the position and deformation of the pipeline. [Result] Through the inspection of actual pipelines, we found that microwave imaging combined with electromagnetic and ray positioning technology has high detection accuracy and reliability, and can effectively detect the deformation or blockage position information of pipelines. Meanwhile, this method also has the advantages of simple operation and fast detection speed.[Innovation]Microwave imaging method combines electromagnetic and ray positioning technology organically, and is a non-contact detection method. It solves the problems of self deformation caused by impact in existing diameter plate methods, damage to pipe walls, and imprecise positioning of pipe deformation positions. This method is expected to be applied to the detection and maintenance of various pipelines, improving the efficiency and accuracy of pipeline maintenance.
Numerical Analysis and Application of Marciniak and Nakazima Experimental Model on the Formability of 304L Sheet
Authors: Zhang Jiguang 
Published: November 2024

Abstract
The comprehensive strength, ductility and high work hardening rate of 304L stainless steel contribute to its excellent mechanical and forming properties. This steel alloy is further distinguished by its notable corrosion resistance, high and low temperature capabilities, and excellent welding performance, making it a widely utilized material in industries such as petroleum, chemical, and nuclear power. In this study, we developed a simulation model based on the testing methods of Marciniak and Nakazima. By incorporating a constitutive model for ductile damage into our simulations, we made predictions regarding strain damage and failure under three different types of strain paths: uniaxial tension, biaxial tension, and plane strain. The results obtained from our finite element analysis were then utilized to generate the Forming Limit Diagram (FLD), which provided valuable insights into the material’s behavior under various forming conditions. Highlighting key differences in the simulation results between the Marciniak and Nakazima test methods. Additionally, the study included a comprehensive simulation verification in the context of bending forming analysis. Notably, the results of the bending analysis fell within the safe range, establishing a solid theoretical foundation for subsequent plate forming and risk assessment.
Experimental Study on the Optimal Operating Envelops of Ejection Supercharging Technology for Unconventional Natural Gas
Authors: Zhou Wei , Jiang Mi , Anqi Du , Zhonghao Dong 
Published: November 2024

Abstract
Ejection supercharging technology could make use of the energy of high pressure gas wells to assist the development of low pressure unconventional natural gas. But at present, the process of adaptability analysis is complicated, the period is long, and the process implementation is difficult in process application. In this paper, based on the production situation of unconventional natural gas, experiments are carried out to investigate the impact of structural and operational parameters on the performance of ejection supercharging. According to analyze the relationship among high, middle and low pressure inlet conditions and their influence on operational performance, as well as the dimensionless processing of pressure parameters, the optimal operating envelops of Ejection supercharging technology for unconventional natural gas is established. Furthermore, A chart is proposed with variable parameters under different conditions to determine the target gas wells for this technology, allowing for a rapid analysis and determination of whether gas wells are suitable for Ejection supercharging technology. And it also get the pressure reduction range of the process acting on the low pressure well, which provides a reference for analyzing the application effect of the process. Finally, The results of the case analysis demonstrate a 100% match rate with the chart established in this paper. The research results greatly simplify the process of well selection, and transform the analysis for specific working conditions one by one into a unified analysis for multiple working conditions, consequently lays a solid foundation for the widespread application of the ejection supercharging technology for unconventional natural gas.
Development and Application of Drilling Intelligent Assistant Decision System
Authors: Wang Jian-long , Wang Yue-zhi , Yu Zhi-qiang , Yu Chen , Zhang Fei-fei , Wang Xue-ying 
Published: November 2024

Abstract
In order to systematically harness the substantial volume of data generated during the drilling process and achieve intelligent analysis and auxiliary decision-making for real-time risk monitoring and warnings during drilling, an intelligent drilling auxiliary decision-making system has been developed. This system integrates various technologies, including physical models, intelligent algorithms, and trend analysis. By analyzing the characteristics of logging data under different operating conditions, an intelligent algorithm capable of automatically distinguishing six types of drilling operating conditions has been established. Taking into account the impact of rock cuttings on the stress on the pipe string and annular pressure loss during the drilling process, coupled frictional torque and cyclic pressure loss calculation models were developed under coupled conditions. Building upon this foundation and considering the trend of deviation between predicted and measured parameters, a monitoring algorithm for detecting stuck drilling, wellbore leakage, and overflow incidents was formulated. The development of the drilling intelligent decision-making system was completed based on a C/S three-layer architecture and a data center. This system has been successfully applied in more than 50 exploration wells of various types, including shale oil and gas horizontal wells and deep wells. The static analysis results demonstrated a compliance rate of 91.5% with on-site monitoring, playing a crucial role in drilling parameter optimization and risk monitoring. The practicality and feasibility of the system have been verified, providing essential support for efficient and safe drilling production.
Investigation the Impact of Different Injection Agents on Tight Oil Reservoirs of Recovery Performance
Authors: Wan Tao , Ding Kun , Qin Jianhua 
Published: November 2024

Abstract
Objectives/Scope: Due to strong water sensitivity and extremely low permeability, conventional water flooding method is not suitable for the Mahu Conglomerate reservoir. In response to the complex reservoir physical properties, different injection agents such as CO2, N2, water and air huff and puff injection were carried out in order to optimize injection parameters for enhanced oil recovery in tight conglomerate reservoirs. Methods, Procedures, Process: By means of NMR, scanning electron microscopy, energy spectrum, pore fluids state in different media after different agents displacement were studied. Displacement and CT testing on different media and post fracturing state were conducted. Through experiments on on-site cores from two different layers, three different injection media (H2O, N2, CO2 and air with different O2 concentration) were tested for enhanced oil recovery. Then, the injection process was performed under different injection pressures. Finally, multiple cycles of enhanced oil recovery tests were conducted corresponding optimal injection pressures. Results, Observations, Conclusions: The remaining oil in the pores is mainly in free and bound states, with a free state of approximately 58% and a bound state of approximately 42%. Four pressures were selected for this test based on the minimum miscibility pressure of CO2 with crude oil: 15MPa, 20MPa, 23MPa, and 25MPa. The recovery factor under different pressures is 6.44%, 8.14%, 10.31%, and 10.38%, respectively. As the huff and puff pressure increases, the recovery of CO2 huff and puff gradually increases, and the increase of recovery is insignificant when the mixture pressure is reached. The gas flooding process involves oil production from large and submicron pores first. As the displacement pressure difference increases, oil production from large pores decreases, with medium pores becoming the main force of oil production, while oil production from nanoscale micropores shows an increasing trend. The increase in oxygen content results in significant development of sub-micron micron scale pores. The gas breakthrough time is long, the capillary force decreases, and air can undergo low-temperature oxidation with crude oil, resulting in an overall oil displacement efficiency of 65.81%. Novel/Additive Information: At present, there is few research on the pore fluid flow and status of oil displacement in tight conglomerate reservoirs with different injection media. This study provides a good understanding of the submicron to nanoscale pore throat structure characteristics of tight oil reservoirs, revealing the state of pore fluids in gravel after displacement by different injection media, and providing support for on-site application of CO2 enhanced oil recovery in tight conglomerate oil reservoirs.
Current Status and Trends in Shale Oil and Gas Drilling Engineering Technology Development at Home and Abroad
Authors: Jing Yu , Bo Zhou , Pingliang Fang , Bing Li , Wenchao Sun , Long Chang 
Published: November 2024

Abstract
Shale oil and gas is an important component of unconventional oil and gas, and the United States has achieved energy independence through the shale revolution. China has abundant unconventional oil and gas resources, and the vigorous development of shale oil and gas is a necessary path for the development of China’s oil and gas industry. By systematically analyzing the developmental characteristics of shale oil and gas major countries, represented by North America, this study compares domestic and foreign shale oil and gas drilling engineering technologies from the perspectives of development process, well construction cycle, drilling parameters, and other aspects. It clarifies the advantages and challenges of Chinese shale oil and gas drilling engineering technology and provides targeted recommendations. The drilling mode for shale oil and gas in China has progressed from single horizontal wells to large-scale platform factory operations, significantly reducing costs and increasing efficiency. However, due to the complex geological conditions of shale formations and poor surface environment, China’s shale oil and gas wells have a horizontal section length about 1000 meters shorter than those in North America, and the well construction cycle is 2-3 times longer. There are still certain gaps in drilling efficiency and operating costs compared to foreign countries. By systematically analyzing the development process and parameter characteristics of shale oil and gas drilling engineering technology at home and abroad, this study clarifies the current status of drilling engineering technology, providing references for the integration and promotion of mature technologies, demonstration of key core technology breakthroughs, and exploration of cutting-edge technology research and development.
Optimization of Welding Process for 825 Bimetallic Composite Pipes Based on Corrosion Testing
Authors: Fu Ling-di , Gao Jian , Li Chao-lang , Zhao Shuai 
Published: November 2024

Abstract
In the process of welding bimetallic composite pipe ring joints, a problem arises where the outer layer of carbon steel dilutes the inner corrosion-resistant alloy lining, resulting in a reduction in corrosion resistance. Therefore, selecting the appropriate welding process and parameters is crucial. This study established manual, semi-automatic, and fully automatic welding processes for welding 825 bimetallic composite pipes, conducted simulated corrosion tests on weld joint ring seams under sulfur-containing conditions, and performed comprehensive evaluations of physical and chemical properties, as well as corrosion resistance. The research findings are as follows: (1) There is a phenomenon of softening in the heat-affected zone of bimetallic composite pipe ring seams. Among them, the fully automatic welding method exhibits significant fluctuations in weld joint strength, higher toughness in the weld and heat-affected zone, and higher hardness values with less variation compared to other welding methods. (2) Under the manual, semi-automatic, and automatic welding processes, the intergranular corrosion rates are 1.08 mm/a, 1.64 mm/a, and 1.11 mm/a, respectively, and the pitting corrosion rates are 0.41 g/m2, 0.25 g/m2, and 0.31 g/m2, respectively. The uniform corrosion rates are 0.0002305 mm/a, 0.0002183 mm/a, and 0.0002197 mm/a, respectively. (3) High-temperature solution heat treatment (above 980 ° C for 30 minutes) can effectively promote the dissolution of carbides into the matrix, improving the intergranular corrosion resistance of alloy 825. The research demonstrates that under sulfur-containing conditions, weld joints obtained using the fully automatic welding process developed in this study exhibit better physical characteristics and corrosion resistance. This can effectively prevent corrosion failures and leakage incidents.
Main Challenges and Strategies to Develop Santos Basin Sub-Salt Fields, Deep water Brazil
Authors: Wang Yaqing , Gao Ce , Jiang Bin , Shang Fanjie 
Published: November 2024

Abstract
Santos basin of Brazil is a hot area of oil and gas exploration and development in the world. Many sub-salt oil fields have been discovered in recent years. The reservoirs are mainly composed of microbial carbonate rocks with strong heterogeneity, which has developed a variety of storage space types. The fluid is complex with high gas oil ratio and CO2 content. The re-injection of produced gas brings uncertainty to the production performance and the stability of facilities. The project investment is huge due to many factors such as deep-water, deep buried and far away from the coastline. The complexity of reservoir and high investment of project make the economic and effective development of reservoir full of great challenges. This paper describes the development strategies of Brazil’s sub-salt deep-water oilfield and the main successful methods to maximize recovery and profits under uncertain conditions. It includes the following three aspects: (1) abundant information acquisition to reduce the main uncertainties; (2) development plan with robustness and flexibility to deal with potential risks; (3) multidisciplinary comprehensive research to evaluate reservoir mode and development mode.