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- Numerical simulation (87)
- Coalbed methane (47)
- Coal mine (39)
- Ordos Basin (31)
- Gas drainage (28)
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- Deep learning (27)
- Permeability (27)
- Pore structure (27)
- Coalbed methane (CBM) (25)
- Deep coalbed methane (24)
- Hydraulic fracturing (23)
- Tar-rich coal (23)
- Directional drilling (21)
- Underground coal mine (20)
- Coal (17)
- Deep coalbed methane (CBM) (17)
- Qinshui Basin (15)
- Horizontal well (14)
- Open-pit coal mine (14)
- Rock burst (14)
- Shale gas (13)
- Underground coal gasification (UCG) (13)
- Fracture (12)
- Machine learning (12)
- Mine water (12)
- Prospect (12)
- Fractal dimension (11)
- Helium (11)
- Intelligent mining (11)
- Microstructure (11)
- Publication Year
Articles 721 - 750 of 1799
Full-Text Articles in Sustainability
Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan, Jiang Chunlu, Huang Wendi, Fu Xianjie, Zheng Liugen, Cheng Shigui, Shan Chonglei
Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan, Jiang Chunlu, Huang Wendi, Fu Xianjie, Zheng Liugen, Cheng Shigui, Shan Chonglei
Coal Geology & Exploration
Hydrogeochemistry research of groundwater in coal mining areas is of great significance to the prevention and control of mine water and the comprehensive utilization of water resources. In terms of the low surfate of Permian sandstone water in Fudong mining area, Anhui Huainan Coalfield, the hydrochemical characteristics, water-rock interaction and low sulfate genesis of sandstone water were studied through water sampling and test by multivariate statistical method, in combination with the hydrogeological condition analysis and the sulfur and oxygen isotope technology. The results show that the Permian sandstone water in the study area is weakly alkaline, with an average TDS …
Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level, Hu Lin, Chen Yongchun, Xu Yanfei, Li Bing, Wang Jin, An Shikai, Chen Chen, Sun Hongjie, Miao Wei
Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level, Hu Lin, Chen Yongchun, Xu Yanfei, Li Bing, Wang Jin, An Shikai, Chen Chen, Sun Hongjie, Miao Wei
Coal Geology & Exploration
Huainan mining area is characterized by a high phreatic water level, as well as a wide range and large area of coal mining subsidence areas, with the water quality monitoring data missing and prominent water environment. Therefore, the evaluation of water quality monitoring and identification of pollution factors in large subsidence area is of great significance to regional water environmental governance. Specifically, the water quality of the subsidence area was evaluated with the Nemerow pollution index method by testing the water samples collected from 175 sampling points in the study area. Meanwhile, the eutrophication state of water bodies was evaluated …
Rate-Of-Penetration (Rop) Prediction Model Based On Formation Characteristics Of Extremely Thick Plastic Mudstone In South China Sea, Zeng Xiaolong, Li Qian, Wei Hongchao, Chen Jiahao, Zhu Haiyan
Rate-Of-Penetration (Rop) Prediction Model Based On Formation Characteristics Of Extremely Thick Plastic Mudstone In South China Sea, Zeng Xiaolong, Li Qian, Wei Hongchao, Chen Jiahao, Zhu Haiyan
Coal Geology & Exploration
In terms of petroleum and gas resources, South China Sea is the important energy replacement area in China. However, most of the reservoirs are buried deep, and the strong plasticity of the formation under high confining pressure and the complex geological environment seriously affect the drilling efficiency. It is also very difficult to accurately predict the ROP. Hence, a set of intelligent ROP prediction model was established for the extremely thick mudstone formation with unique viscoelastic and strong plastic characteristics in South China Sea. The model took the actual data of 10 wells in an area of South China Sea …
Methods For Estimating Carbon Emissions From Coals In Underground Mines: A Case Study Of The Western Fukang Mining Area, Peng Rendong, Wei Bo, Li Xin, Zhang Ji, Zhang Zizhao, Wang Bo, Zhang Na, Cui Deguang
Methods For Estimating Carbon Emissions From Coals In Underground Mines: A Case Study Of The Western Fukang Mining Area, Peng Rendong, Wei Bo, Li Xin, Zhang Ji, Zhang Zizhao, Wang Bo, Zhang Na, Cui Deguang
Coal Geology & Exploration
Carbon emissions have come into sharp focus of human society. The carbon emissions from coals rank as the most predominant part of China’s total carbon emissions. Presently, there is no available study on the accurate calculation of carbon emissions from coals in typical underground mines in Xinjiang, with the CH4 emission even overlooked. This study centers on the carbon emissions from coals in underground mines in the western Fukang mining area. As per the occurrence laws of CH4 and CO2 in coal seams, as well as coal mining plans, this study classified the sources of carbon emissions …
A New Physics-Informed Method For The Fracability Evaluation Of Shale Oil Reservoirs, Li Yuwei, Li Zijian, Shao Lifei, Tian Fuchun, Tang Jizhou
A New Physics-Informed Method For The Fracability Evaluation Of Shale Oil Reservoirs, Li Yuwei, Li Zijian, Shao Lifei, Tian Fuchun, Tang Jizhou
Coal Geology & Exploration
The accurate evaluation of reservoir fracability is an essential prerequisite for the fracturing design and post-fracturing productivity evaluation of reservoirs. Rock mechanical parameters have been applied to the fracability evaluation of shales presently, exhibiting great field application performance. Accordingly, it is crucial to obtain accurate rock mechanical parameters. This study developed a physics-informed neural network (PINN) model. Driven by data and physical information, the PINN model can accurately predict rock mechanical parameters using only a small amount of data. To verify its performance, the PINN model was compared with the artificial neural network, random forest, and XGBoost models. The comparison …
Water Inrush Mechanism Of Coal Mine Shaft Fracture Under Fluid-Solid Coupling, Xue Weipei, Shen Lei, Yao Zhishu, Cheng Hua, Rong Chuanxin
Water Inrush Mechanism Of Coal Mine Shaft Fracture Under Fluid-Solid Coupling, Xue Weipei, Shen Lei, Yao Zhishu, Cheng Hua, Rong Chuanxin
Coal Geology & Exploration
The occurrence of coal mine shaft fractures and water inrush accidents is alarmingly frequent, endangering the lives of underground personnel and compromising mine safety. To comprehend the influence of confined groundwater in the process of shaft fracture and the formation mechanism of water inrush channels, a model test was devised using similarity theory and coupled fluid-solid numerical simulation technology. The findings reveal that direct contact between the shaft lining and pressurized water hinders the development of load-bearing and deformation capacities. This is specifically evidenced by the premature appearance of the yield point, a reduction in peak strength and strain, and …
Zoned Prediction Of Water Inflow After Dewatering Of Working Face Based On Waterrichness Zoning Of Aquifer, Yang Lei, Lei Fangchao, Hou Enke, Lu Bo, Feng Dong, Zhao Kaixing
Zoned Prediction Of Water Inflow After Dewatering Of Working Face Based On Waterrichness Zoning Of Aquifer, Yang Lei, Lei Fangchao, Hou Enke, Lu Bo, Feng Dong, Zhao Kaixing
Coal Geology & Exploration
As the weathered bedrock and burned rock aquifers seriously threaten the production safety of mines in the Jurassic coalfield of northern Shaanxi Province, accurate prediction of their waterrichness and water inflow at the working face is of great significance for water control in mines. Aiming at the weathered bedrock and burned rock aquifers with close hydraulic connection, the area where working face 15217 of Shaanxi Hongliulin Coal Mine is located was taken as the study area. Meanwhile, the aquifer thickness, lithological combination index, index of rock burning and weathering degree and core recovery was taken as the evaluation indexes. The …
Study On Mesoscopic Failure Characteristics Of Layered Red Shale, Ma Zhenqian, Zhou Lang, Zuo Yujun, Zhang Jimin, Zou Yihuai, Cao Yunqin
Study On Mesoscopic Failure Characteristics Of Layered Red Shale, Ma Zhenqian, Zhou Lang, Zuo Yujun, Zhang Jimin, Zou Yihuai, Cao Yunqin
Coal Geology & Exploration
To study the mesoscopic failure characteristics of the layered red shale, uniaxial mechanical experiments were carried out by applying DSTD-1000 electro-hydraulic servo rigid pressure on the red shale with different bedding angles. Meanwhile, SEM and XRD experiments were implemented on debris to obtain its mechanical parameters, failure characteristics, microstructure, and relative content of components. Based on this, models of the red shale with different bedding angles were constructed using the discrete element PFC3D for the uniaxial compression experiments to study the mesoscopic failure characteristics of red shale. The results show that: (1) When the bedding angle θ=30°, 45°, …
An Attention Mechanism-Based Cnn-Bilstm Real-Time Transient Electromagnetic Method, Gu Yao, Xie Haijun, Zhou Zipeng, Li Lu
An Attention Mechanism-Based Cnn-Bilstm Real-Time Transient Electromagnetic Method, Gu Yao, Xie Haijun, Zhou Zipeng, Li Lu
Coal Geology & Exploration
The one-dimensional transient electromagnetic (TEM) method is time-consuming and suffers other drawbacks such as difficult parameter adjustment and heavy dependence on the initial model. Therefore, this study proposed a real-time TEM inversion method—the Attention mechanism-based convolutional neural network (CNN) - bidirectional Long Short-Term Memory (BiLSTM) (AC-BiLSTM). By fully utilizing the time difference, the AC-BiLSTM performed model training in non-observation time and the real-time inversion of the collected data in observation time. With the measured data mixed with a certain proportion of data obtained from forward modeling as the dataset, the sampling time and apparent resistivity as the input features in …
Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun
Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun
Coal Geology & Exploration
In-seam waves are commonly applied to the advance detection of hidden faults in front of mining faces. However, coal seams, which have viscoelasticity actually, imposing absorptive and attenuation effects on in-seam waves. To investigate the wave field characteristics and propagation patterns of in-seam waves in viscoelastic coal seam media, this study built a three-dimensional geological model of coal measures with faults based on Kelvin-Voigt’s first-order velocity-stress equation. Using this equation, three-dimensional finite-difference numerical simulation was carried out. The results indicate that (1) for reflected in-seam waves in viscoelastic media, which exhibit high energy attenuation, their propagation and attenuation characteristics are …
Manipulator Trajectory Planning Method Of Anchor Drilling Robot, Lei Mengyu, Zhang Xuhui, Yang Wenjuan, Dong Zheng, Wan Jicheng, Zhang Chao, Du Yuyang
Manipulator Trajectory Planning Method Of Anchor Drilling Robot, Lei Mengyu, Zhang Xuhui, Yang Wenjuan, Dong Zheng, Wan Jicheng, Zhang Chao, Du Yuyang
Coal Geology & Exploration
In order to improve the support efficiency of coal mine roadway and the automation intelligence of heading face, an anchor drilling robot integrating the cantilever roadheader and the six-degree-of-freedom manipulator was designed, and studied on the anchor drilling sequence planning strategy and the drilling boom trajectory planning method. Firstly, the kinematics model of the manipulator structure was established based on the improved DH method. On this basis, the forward and inverse kinematics solutions were analyzed, and the spatial position and the corresponding joint variable values of the drilling rig were calculated. Secondly, the manipulator space was analyzed based on Monte …
Research Progress Of Rotary Steerable System And Its Control Methods, Li Wei, Mou Lei, Zhou Xiancheng, Tan Xianhui, Fu Quan
Research Progress Of Rotary Steerable System And Its Control Methods, Li Wei, Mou Lei, Zhou Xiancheng, Tan Xianhui, Fu Quan
Coal Geology & Exploration
Rotary steerable system is a shining pearl in directional drilling technology and an important technical means to realize the low-cost and efficient development of oil and gas resources. First of all, the basic structure of the rotary steerable system was introduced. According to the different steering modes and bias effects, the rotary steerable system is divided into five categories: static push-the-bit type, dynamic push-the-bit type, static pointing type, dynamic point-the-bit type and mixed type, for which the steering principle was analyzed one by one. Secondly, according to the research and application of rotary steerable system technology at home and abroad, …
Pfc Numerical Analysis On Crack Initiation Mechanism Of Fracture Grouting In Top Of Ordovician Limestone, Liu Zhaoxing, Zhang Qi
Pfc Numerical Analysis On Crack Initiation Mechanism Of Fracture Grouting In Top Of Ordovician Limestone, Liu Zhaoxing, Zhang Qi
Coal Geology & Exploration
The advanced regional grouting is an effective means to prevent and control the water hazard of limestone in coal seam floor, and the fracture grouting projects is a key link to determine the effect of the grouting in floor against water hazard. However, due to the unclear understanding of the fracture initiation mechanism of the injected limestone stratum, the grouting pressure, grout water-cement ratio and other grouting parameters in the process of fracture grouting are not effectively controlled. Thus, it is difficult to guarantee the grouting effect. In order to solve the above problems, numerical simulation calculation was conducted for …
Table Of Contents, The Editors
Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian
Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian
Coal Geology & Exploration
To achieve an elevated accuracy in the prediction of coal and gas outbursts, this study conducted mercury injection capillary pressure (MICP) tests and isotherm adsorption experiments on selected six coal samples with different metamorphic degrees. Furthermore, it calculated the gas expansion energy of coals and analyzed the evolutionary characteristics of the gas expansion energy of coals with different metamorphic degrees, as well as their relationships with the prediction indices of coal and gas outbursts. The results of this study are as follows: (1) The differences in the pore structures and adsorptivity of coals with different metamorphic degrees led to different …
A Method For Identifying Faults Within Mining Faces Based On Spatial Statistics, Feng Yajie, Wen Guangchao, Wu Bingjie, Hu Zudong
A Method For Identifying Faults Within Mining Faces Based On Spatial Statistics, Feng Yajie, Wen Guangchao, Wu Bingjie, Hu Zudong
Coal Geology & Exploration
Minor faults within mining faces of coal mines severely affect gas drainage and coal seam mining. Accurately identifying parameters such as positions, throws, and attitudes of these faults is of great significance for the safe production of coal mines. To effectively reduce gas emissions, prevent gas explosions, and exploit and utilize gas resources, many gas drainage holes have been drilled during the construction of coal mines, providing favorable engineering conditions for identifying minor faults within coal seams. Compared with the conventional fault identification methods, which rely on the expertise of geologists, the identification model based on mathematical statistics and space …
An Improved Automated Testing Model For Maceral Groups In Coals Based On Deeplabv3+, Hu Jinwei, Xi Zhenghao, Xu Guozhong, Li Zhongfeng, Liu Xiang
An Improved Automated Testing Model For Maceral Groups In Coals Based On Deeplabv3+, Hu Jinwei, Xi Zhenghao, Xu Guozhong, Li Zhongfeng, Liu Xiang
Coal Geology & Exploration
The identification of maceral groups in coals plays a critical role in analyzing the chemical properties of coals. However, manual identification is laborious and requires high expertise. Existing computer-assisted identification methods, mostly adopting deep learning-based semantic segmentation models, fail to accurately identify maceral groups in coals due to complex compositions of microscopic coal images and the presence of transitional components. Therefore, this study proposed an improved DeeplabV3+ semantic segmentation model integrating the Swin Transformer backbone network and the SkNet. First, to deal with the challenge of feature extraction caused by the intertwined maceral groups and the presence of transitional components …
Discovery And Generation Mechanisms Of Epigenetic Biogenic H2S From Coal Seams In The Fukang Block, Southern Junggar Basin, China, Yan Peipei, Su Xianbo, Zou Chenglong, Zhao Weizhong, Wang Lufei, Fu Haijiao
Discovery And Generation Mechanisms Of Epigenetic Biogenic H2S From Coal Seams In The Fukang Block, Southern Junggar Basin, China, Yan Peipei, Su Xianbo, Zou Chenglong, Zhao Weizhong, Wang Lufei, Fu Haijiao
Coal Geology & Exploration
In the Fukang block located in the eastern part of the southern Junggar Basin, coalbed methane (CBM) from CBM wells exhibits a gradually increasing H2S concentration in the process of CBM production via water drainage, severely threatening production safety. Based on the CBM exploration and extraction data, as well as the anaerobic fermentation experiments, this study preliminarily investigated the causes of abnormal H2S concentrations during the CBM production in the Fukang block. As indicated by the gas content test in the CBM exploration stage, the original CBM showed a low H2S concentration of only …
Water-Blocking Performance Of Laterite In Weak Deposition Areas Of Neogene Baode Formation And Its Significance Of Resource Exploitation, Zeng Yifan, Bao Han, Wu Qiang, Meng Shihao, Hua Zhaolai, Miao Yanping, Zhang Ye, Bu Wenyang
Water-Blocking Performance Of Laterite In Weak Deposition Areas Of Neogene Baode Formation And Its Significance Of Resource Exploitation, Zeng Yifan, Bao Han, Wu Qiang, Meng Shihao, Hua Zhaolai, Miao Yanping, Zhang Ye, Bu Wenyang
Coal Geology & Exploration
The in-depth study on the water-blocking performance of laterite in the weak deposition areas of the key aquiclude is of significant importance for mine production safety and ecological water resource protection. Specifically, the borehole data were re-optimized based on the regional sedimentary characteristics, the thickness distribution pattern of laterite deposit in Yushen mining area was studied, and the micro-engineering characteristics and control factors related to the water-blocking performance of laterite were explored. The results show that the deposition thickness of laterite gradually increases from northwest to southeast, the distribution of laterite becomes extremely uneven with the evolution of rivers, and …
Prediction Of Rockburst Intensity Grade Based On Convolutional Neural Network, Li Kangnan, Wu Yaqin, Du Feng, Zhang Xiang, Wang Yiqiao
Prediction Of Rockburst Intensity Grade Based On Convolutional Neural Network, Li Kangnan, Wu Yaqin, Du Feng, Zhang Xiang, Wang Yiqiao
Coal Geology & Exploration
Rockburst is one of the urgent problems to be addressed in the process of deep resource extraction. In order to predict the rockburst disasters safely and efficiently, a rockburst intensity grade prediction model (MICE-CNN) based on the Multiple Imputation by Chained Equations (MICE) and Convolutional Neural Network (CNN) was proposed. Specifically, a predictive indicator system was established based on the main influencing factors and the acquisition conditions of rockburst. A total of 120 sets of raw data from rockburst cases were collected, with the outliers processed by pauta criterion. Then, the missing data were interpolated with the four interpolation models …
Numerical Model Of Two-Region Flow By Constant-Head Pumping In An Unconfined Aquifer, Shi Pengyu, Zong Yijie, Teng Kaiqing, Liu Jianjun, Xiao Liang
Numerical Model Of Two-Region Flow By Constant-Head Pumping In An Unconfined Aquifer, Shi Pengyu, Zong Yijie, Teng Kaiqing, Liu Jianjun, Xiao Liang
Coal Geology & Exploration
In order to reveal the mechanism of two-region Darcian and non-Darcian flow induced by constant-head pumping tests in unconfined aquifers, a numerical model of well flow by constant-head pumping underground based on finite difference solution was proposed. In the model, it is assumed that the aquifer is divided into two regions according to the pumping flow characteristics: the finite non-Darcian flow region near the pumping well and the semi-infinite Darcian flow region far away from the pumping well. Specifically, the flow regime in the non-Darcian flow region was simulated by the Izbash’s equation, and the reliability of the proposed solution …
Status And Development Of Intelligent Drilling Tools For Coal Mine, Gao Xiaoliang
Status And Development Of Intelligent Drilling Tools For Coal Mine, Gao Xiaoliang
Coal Geology & Exploration
As an important part of intelligent drilling, the intelligence of drilling tool system plays a crucial role in the intelligent development of coal mine underground drilling. In order to deeply explore the development direction of intelligent drilling tools, the research results and technical characteristics of intelligent drilling tools in coal mines were systematically sorted out from the aspects of directional drilling tools, measurement while drilling (MWD) system, intelligent drilling pipes and drill bits with reference to the experience in development of oil and gas industry, and the existing shortcomings were also summarized. It is pointed out that screw motor is …
Research On Three-Stage Automatic Hole Packer For Gas Extraction Drilling In Underground Coal Mine, Wang Qingfeng, Shi Shuhan, Xin Dezhong, Chen Hang, Zhang Shitao
Research On Three-Stage Automatic Hole Packer For Gas Extraction Drilling In Underground Coal Mine, Wang Qingfeng, Shi Shuhan, Xin Dezhong, Chen Hang, Zhang Shitao
Coal Geology & Exploration
In view of the requirements of hole sealing during gas extraction drilling in underground coal mine for manual packer installation and sealing material injection, as well as the low automation level of hole sealing technology, a three-stage automatic hole packer for gas extraction drilling in underground coal mine was developed, with the appearance similar to the drill pipe. The hole packer could be mechanized into the drilling hole by an automatic drilling machine, and realize the automatic injection of sealing material. Herein, the Mooney-Rivlin hyperelastic constitutive model was used to represent the strain energy function by the finite element analysis …
Intelligent Optimization And Control Technology For Drilling Process Of Coal Mine Tunnels, Yao Ningping, Wu Min, Chen Luefeng, Lu Chengda, Fan Haipeng, Zhang Youzhen, Li Wangnian, Yao Ke
Intelligent Optimization And Control Technology For Drilling Process Of Coal Mine Tunnels, Yao Ningping, Wu Min, Chen Luefeng, Lu Chengda, Fan Haipeng, Zhang Youzhen, Li Wangnian, Yao Ke
Coal Geology & Exploration
The harsh environment for drilling construction of coal mine tunnel, complex coal seam structure and complicated operation procedures can cause low drilling efficiency and high drilling cost. For this reason, it is imperative to carry out studies on the optimization and control technology for the drilling process of coal mine tunnel. Herein, study was conducted from intelligent identification of lithology of coal-bearing formation, intelligent optimization of drilling parameters and their intelligent control, focusing on the key technology for control of drilling process of coal mine tunnel. First, in order to accurately determine the type of coal-bearing formation, an intelligent identification …
Research Status And Development Trend Of Near-Bit Mwd In Underground Coal Mine, Hao Shijun, Chu Zhiwei, Li Quanxin, Fang Jun, Chen Long, Liu Jianlin
Research Status And Development Trend Of Near-Bit Mwd In Underground Coal Mine, Hao Shijun, Chu Zhiwei, Li Quanxin, Fang Jun, Chen Long, Liu Jianlin
Coal Geology & Exploration
Near-bit meusurement while drilling (MWD) integrates several key technologies such as near-bit multi-parameter measurement, power supply and communication across positive displacement motor drills, turbine continuous power generation and high-speed mud pulse wireless transmission, capable of obtaining various types of parameters near the bit. It is one of the key components of intelligent drilling technology in underground coal mine. Herein, the limitation of the existing technology applied in coal mine was analyzed with full reference to the development experience and development path of near-bit MWD in the field of surface oil and gas drilling. Meanwhile, the research idea of near-bit MWD …
Continuous And Discontinuous Numerical Simulation Of The Rock Breaking Process Of Pdc Drill Bit Under Composite Impact, Qin Chengshuai, Sun Hongbin, Li Liping, Liu Xuegang, Liu Zhihui, Feng Chun, Sun Zizheng
Continuous And Discontinuous Numerical Simulation Of The Rock Breaking Process Of Pdc Drill Bit Under Composite Impact, Qin Chengshuai, Sun Hongbin, Li Liping, Liu Xuegang, Liu Zhihui, Feng Chun, Sun Zizheng
Coal Geology & Exploration
Composite impact drilling is a novel rock-breaking technique that combines both axial and torsional impacts. To address the issues of complex failure mechanisms and unclear rock-breaking mechanisms under the axial-torsional impacts on rock by Polycrystalline Diamond Compact (PDC) drill bits, a FEM-DEM rock model based on shared nodes was established using the Continuous Discontinuous Element Method (CDEM), and the rationality of this computational model was verified through laboratory uniaxial compression experiments. Besides, a composite impact motion model for single drill bit was built through the secondary development of JavaScript, and the composite impact rock-breaking process of single PDC drill bit …
Application Of Intelligent Direct Push Measurement While Drilling Device For Environmental Geological Surveys, Sun Pinghe, Zhou Shengwei, Cao Han, Gao Qiang, Cheng Gongbi, Zhang Hui
Application Of Intelligent Direct Push Measurement While Drilling Device For Environmental Geological Surveys, Sun Pinghe, Zhou Shengwei, Cao Han, Gao Qiang, Cheng Gongbi, Zhang Hui
Coal Geology & Exploration
In order to solve the technical challenges of inaccuracy and poor credibility of contaminant survey results due to the low accuracy of drilling trajectories in environmental geological surveys, the structural and functional characteristics of the existing direct-push drilling tools were analyzed. On this basis, the method of near-bit measurement while drilling using single-action combination was proposed. An intelligent measurement-while-drilling (MWD) device was developed, a laboratory platform monitoring module was established, a set of monitoring software was developed, and the stability and reliability of the intelligent MWD device was analysed. Then, verification tests have been carried out on the laboratory platforms …
Wear Law And Design Of Assembling Diamond Bit Based On Finite Element Analysis, Yang Zhan, Tan Songcheng, Yang Kaihua, Fang Xiaohong
Wear Law And Design Of Assembling Diamond Bit Based On Finite Element Analysis, Yang Zhan, Tan Songcheng, Yang Kaihua, Fang Xiaohong
Coal Geology & Exploration
In addition to coring drilling, full (non-coring) drilling also occupies a large proportion in the energy exploration and development. Non-coring drilling can reduce the high time cost of lifting and lowering work required for coring, thereby increasing the net drilling time, improving the drilling efficiency and reducing the drilling costs. The traditional non-coring drill bits are prone to uneven wear on the bit surface during the drilling process. To identify and improve this law of uneven wear, it was herein proposed to use the assembling non-coring bit to improve the eccentric wear of bit. For this reason, numerical simulation analysis …
Table Of Contents, The Editors
Attenuation Model And Law Of High-Frequency Drilling Fluid Pressure Wave, Zhou Botao, Su Yinao, Wang Jiajin
Attenuation Model And Law Of High-Frequency Drilling Fluid Pressure Wave, Zhou Botao, Su Yinao, Wang Jiajin
Coal Geology & Exploration
The technology of transmitting high-frequency drilling fluid pressure wave information with high transmission rate. It is also one of the key technologies to achieve the automated and intelligent drilling. However, the field application of this technology is hindered by the substantial attenuation experienced by high-frequency drilling fluid pressure waves during the transmission process. Thus, exploring the attenuation characteristics of these waves is crucial for the development of high-speed transmission technology. Herein, it is assumed that the drilling fluid pressure is equivalent on the same section of drill string, and the flow rate of drilling fluid is radially distributed. On this …