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Articles 2341 - 2370 of 3214
Full-Text Articles in Sustainability
Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun
Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun
Coal Geology & Exploration
The CBM production is usually low and development effect is poor in China, which are mainly due to the poor adaptability of the stimulation measures to the geological conditions. This article, based on the low-yield reasons for vertical CBM wells in Zhengzhuang block in southern Qinshui basin, puts forth corresponding stimulation measures, analyzes the mechanism and the geological adaptability, optimizes the parameters of specific stimulation measures and carries out pilot test. The research and practices show that in deeply buried area, fractures are difficult to form, and re-fracturing technology can make the fracture turn and increase the crack length, which …
Estimation Method And Application Of Free Gas Content In Coal, Jiang Wenping, Zhang Qun, Zhang Peihe, Dong Mintao, Tian Xinjuan, Ru Ting
Estimation Method And Application Of Free Gas Content In Coal, Jiang Wenping, Zhang Qun, Zhang Peihe, Dong Mintao, Tian Xinjuan, Ru Ting
Coal Geology & Exploration
In order to study the distribution characteristics of free gas content in coal reservoirs, based on the understanding that free gas mainly exists in coal pores, the estimation method of free gas content is optimized. Based on the test data of coalbed methane arameters of 42 groups of coals with different ranks from lignite to anthracite in typical coal-bearing areas of China, the free gas content of different coal samples were calculated by using the optimized method of free gas content estimation, and compared with the results of desorption gas content. The results show that the ratio of free gas …
Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng
Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng
Coal Geology & Exploration
In order to fully understand the reservoir pressure variation characteristics of coalbed methane wells in the southern block of Shizhuang and based on the analysis of reservoir geological parameters and the analysis of actual production data, the reservoir pressures of different types of production wells are analyzed. The specific analysis of the drainage control and reservoir sensitivity effects is also carried out based on the abnormal wells. The results showed that the reservoir lamination of coalbed methane wells in the southern block of Shizhuang can be divided into three types, namely type of rapid pressure drop, type of medium-term stability …
Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao
Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao
Coal Geology & Exploration
In order to solve the problem of fluid and gas leakage in coal seam gas well, a self-adjusting deflected wellhead sealing device suitable for coal seam gas wells is developed. The device consists of three parts:Smooth rod sealing box, self-adjusting deflected part and lower sub. The self-adjusting deflected part is a smart combination of universal joint and high pressure flexible rubber tube, which makes the sealing box and the polished rod always keep good concentricity. Practical application shows that this kind of polished rod sealing device has reliable sealing performance, simple structure and the prospect of popularization and application.
Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin
Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin
Coal Geology & Exploration
Contact angle and pore size are important factors affecting soil wettability, permeability and capillarity. In order to further understand the capillary characteristics and permeability of unsaturated loess, the contact angle test and mercury intrusion test of unsaturated loess were carried out. The relationship between pore size and contact angle was analyzed in details. Moreover, the variation of pore and contact angle with depth was discussed. It is found that the contact angle of loess in the dry state is higher than the contact angle of loess in the natural state; as the depth of the formation increases, the contact angle …
Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan
Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan
Coal Geology & Exploration
According to the high mining speed of modern mines in China, the fracture characteristics of rock mass under different uniaxial loading rate was systematically analyzed. Based on the geological condition of deep rock mass in Jining area, the optimum mortar composed of 425 Portland cement, sand with particle size less than 2 mm, gypsum, water and high efficient water reducer was used, which had the mechanical properties similar to real rock mass was ascertained. Applying the triaxial rock test system of coupled stress-seepage and PCI-2 real-time monitoring system of AE, the fracture process of specimens of large size under biaxial …
A New Instability Criterion Of Double Strength Reduction Method For Slope, Fang Hongwei, Wu Jianxun, Hou Zhenkun
A New Instability Criterion Of Double Strength Reduction Method For Slope, Fang Hongwei, Wu Jianxun, Hou Zhenkun
Coal Geology & Exploration
Based on the slip line field theory(SLFT), a new instability criterion of strength reduction method with double re-duction factors for homogeneous slopes was proposed. It is judged that the slope is in the limit equilibrium state when the slope contour under limit equilibrium state(abbreviated as the critical slope contour) calculated by the SLFT intersects with the slope line at the toe. The critical curve was constructed in the plane of the inverse of the double reduction factors, and the comprehensive safety factor was derived. The slope calculation results show that three relative position relationships between the initial point and the …
The Effect Of Viscoelasticity And Velocity Anisotropy On The Reflections Of A Thin Bed, Chen Benchi, Wang Chao, Chen Changxing, Shi Lei
The Effect Of Viscoelasticity And Velocity Anisotropy On The Reflections Of A Thin Bed, Chen Benchi, Wang Chao, Chen Changxing, Shi Lei
Coal Geology & Exploration
The coal seam is a typical thin bed characterized by much lower elastic impedance than that of the surrounding rock. Coal seam has viscoelasticity and velocity anisotropy and its reflection amplitude changes with frequency. In order to analyze the effect of viscoelasticity and velocity anisotropy on seismic responses of a thin bed, this paper aims at a thin-bed model with strong impedance contrast and simulates seismic responses under three different assumptions, elastic and velocity isotropy, viscoelastic and velocity isotropy, and viscoelastic and velocity anisotropy, through numerical simulation method based on wave equations. Comparison of these seismic reflections shows that the …
Acquisition Platform Of Frequency Domain Ip Signal, Fu Guohong, Zhang Qianfeng, Cheng Hui, Xie Tiancai
Acquisition Platform Of Frequency Domain Ip Signal, Fu Guohong, Zhang Qianfeng, Cheng Hui, Xie Tiancai
Coal Geology & Exploration
In order to improve the versatility of the induced polarization(IP) signal receiver of traditional frequency domain, a signal acquisition platform was designed, which can acquire and process IP signals of frequency domain such as variable-frequency signals, dual-frequency IP signals, and pseudo-random multi-frequency IP signals and so on. Hardware circuits were established based on STM32 to execute low-pass filtering, program-controlled amplification, analog-to-digital conversion, and data communication. The host computer was developed in LabVIEW to achieve parameter settings, digital filtering, spectrum analysis, amplitude measurement and calculation to obtain target parameters such as PFE, and has waveform display and playback, data storage and …
The Influence Of Grounding Grid On Electromagnetic Detection Of Goaf, Xu Xing, Weng Ling, Li Shiqiang, Liu Guoqiang
The Influence Of Grounding Grid On Electromagnetic Detection Of Goaf, Xu Xing, Weng Ling, Li Shiqiang, Liu Guoqiang
Coal Geology & Exploration
The existence of underground goaf can easily cause tilting and settlement of power towers, which is a major hidden factor in the safe and stable operation of power grid. To detect the mine goaf under the power transmission corridor is of great significance. When there is a grounding grid in the detection area, the grounding grid will have certain influence on the measured value. In this paper, the detection of mine goaf in the presence of a grounding grid is presented. Based on the theoretical analysis, the mathematical model is built, and the simulation model is conducted. The influence of …
Design And Application Of Multi-Section Bundled Bag Wire-Line Coring Drilling Tools, Han Yi, Zhang Shaohe, Bai Rui, Sun Pinghe, Shu Biao, Cao Han, Zhang Xinxin
Design And Application Of Multi-Section Bundled Bag Wire-Line Coring Drilling Tools, Han Yi, Zhang Shaohe, Bai Rui, Sun Pinghe, Shu Biao, Cao Han, Zhang Xinxin
Coal Geology & Exploration
Because the existing conventional wire-line coring drilling tool lacks the water-proof and core-protecting device, the broken core is easily eroded when the core is drilled in a complicated layer such as loose, weak, broken layers and the core is easy to fall off during the lifting process, so that the coring rate and core quality are not up to the design requirements, and even core can not be taken to. In response to the above problems, a bag-type wire-line coring drilling tool was designed. The drill adds a multi-section bundled bag assembly structure to the conventional wire-line coring drilling tool …
Study On Local Volume Breakage Of Diamond-Impregnated Bit, Sun Jiwei, Shen Lina, Yang Gansheng, Ye Jichao
Study On Local Volume Breakage Of Diamond-Impregnated Bit, Sun Jiwei, Shen Lina, Yang Gansheng, Ye Jichao
Coal Geology & Exploration
To solve the problem of high energy consumption and slow drilling speed of impregnated diamond drill in hard rock, the method of volume crushing to improve drilling efficiency was put forward. In order to study the crushed volume of impregnated diamond bit in hard rock, firstly, an test of single diamond pressed into rock was designed. According to the experimental data, the first partial broken volume when single diamond was pressed into rock was the volume breakage type of impregnated diamond bit. Then the mathematical model of optimal drilling pressure and speed in first partial broken volume was deduced. By …
Evaluation Technology For Key Monitoring Area Of Early Warning Of Water Inrush From The Floor Of Working Face In Coal Mine, Liu Demin, Yin Shangxian, Lian Huiqing
Evaluation Technology For Key Monitoring Area Of Early Warning Of Water Inrush From The Floor Of Working Face In Coal Mine, Liu Demin, Yin Shangxian, Lian Huiqing
Coal Geology & Exploration
Accurately delineating the key monitoring areas for water inrush warning of the floor of working face in coal mine and realizing the spatial matching of the monitoring position of the early warning system and the location of potential water inrush points are one of the urgent problems to be solved in the warning of water inrush from the floor of working face in coal mine. In order to study the evaluation technology for key monitoring area of water inrush warning of the floor of working face in coal mine, hydrogeological analysis, GIS spatial analysis and ANN prediction were used to …
Spatial Distribution And Formation Of Groundwater Hydrochemistry In Huainan Coalfield, Wang Zitao, Liu Qimeng, Liu Yu
Spatial Distribution And Formation Of Groundwater Hydrochemistry In Huainan Coalfield, Wang Zitao, Liu Qimeng, Liu Yu
Coal Geology & Exploration
In order to study the spatial distribution of groundwater in Huainan coalfield and the intensity of various hydrochemical actions, the coalfied is divided into the northern district with thicker loose beds and the southern district with thinner loose beds. Hydrochemical test data of main water-inrushing aquifers in 16 mines in these two areas were collected and statistically analyzed, ion combination method and Gibbs diagram were used to study the groundwater hydrochemical characteristics of each aquifer in north and south areas. The results indicate that TDS of aquifer is positively correlated with the burial thickness of unconsolidated formation. With the increase …
Influence Of The Freezing-Thawing Cycles On Soil-Water Characteristics Of Soil In Open-Pit Mine Dumping Sites, Wang Xuedong, Li Shiyu, Sun Yanfeng, Ye Guo
Influence Of The Freezing-Thawing Cycles On Soil-Water Characteristics Of Soil In Open-Pit Mine Dumping Sites, Wang Xuedong, Li Shiyu, Sun Yanfeng, Ye Guo
Coal Geology & Exploration
In order to study the unsaturated soil-water characteristics of soil under freezing-thawing cycles, the soil in Yuanbaoshan open-pit mine dumping site was selected as the research object. The variation of matrix suction and structure of soil under different water content after different freezing-thawing cycles was studied. The results show that during the same freezing-thawing cycles, the matrix suction increases with the decrease of water content, and the range increases gradually. The soil-water characteristic curve can be divided into sensitive stage, sub-sensitive stage and insensitive stage. With the increase of freezing-thawing cycles, the curvature of soil-water characteristic curve increases first and …
Similar Model Test And Mechanical Analysis Of Fault Structure, Song Yanqi, Wang Shilei, Sun Chuan, Hao Liangjun
Similar Model Test And Mechanical Analysis Of Fault Structure, Song Yanqi, Wang Shilei, Sun Chuan, Hao Liangjun
Coal Geology & Exploration
The pre-existing fault specimens were made to confirm the actual stratum mechanical properties based on the similarity theory. Then the mechanism of failure mode of pre-existing fault was analyzed under the crack tip stress field theory. The results show that with the increase of load, the microcracks develop gradually and propagate, and the propagation path tends to the loading direction. In the process of crack propagation, multiple branch paths are generated, and then the cracks merge with each other to destroy the specimen. The stress field theory can be used to determine the newly generated fracture direction, which is consistent …
Fractal Theory-Based Investigation Of The Optimal Interval Of Minimum Pore Radius Of Sandstone, Xu Lulu, Dong Shuning, Dai Zhenxue, Xu Bin, Yin Shangxian, Zhou Yan, Chen Junjun
Fractal Theory-Based Investigation Of The Optimal Interval Of Minimum Pore Radius Of Sandstone, Xu Lulu, Dong Shuning, Dai Zhenxue, Xu Bin, Yin Shangxian, Zhou Yan, Chen Junjun
Coal Geology & Exploration
Permeability is a main parameter for evaluation of water conductivity of porous media, and it is a macroscopic feature of micro-pore structure of water-conducting media. To obtain the geometry parameters of microscopic pores, we performed scanning electron microscopy(SEM) on sandstone samples. The image processing techniques were also applied in calculation of different statistical parameters(e.g., fractal dimensions) and geometrical parameters. Then, fractal theory was introduced to investigate the influence of micro pore structure on permeability. At the same time, the minimum pore radius rmin interval acting on the seepage was obtained by the measured permeability values. This interval can be …
Stability Of Cement-Based Grouting Slurry And Test Of Its Bleeding Law, Xu Bin, Dong Shuning, Xu Lulu, Zhou Yan, Chen Junjun, Dai Zhenxue, Wang Hao
Stability Of Cement-Based Grouting Slurry And Test Of Its Bleeding Law, Xu Bin, Dong Shuning, Xu Lulu, Zhou Yan, Chen Junjun, Dai Zhenxue, Wang Hao
Coal Geology & Exploration
To better understand the stability performance and bleeding property of cement-based grouting slurry, a new test device was improved to get the separated-water thickness value of slurry samples at every time, and these samples were made and sorted according to the certain proportion of the water-solid ratio(0.6:1 to 3:1), fly ash content(0-90%) and sodium silicate content(0-12%). The growth theory for separated-water thickness was introduced, and the growth curves for all formulations were plotted. The slurry stability measurement method was classified, and the equivalence relation between the direct measurement method of slurry stability and the indirect measurement method was verified. The …
Experimental Study Of Three-Component Down-Hole Tem For Detecting Water-Filled Goaf, Yao Weihua, Wang Peng, Li Mingxing, Su Chao, Cheng Siyuan
Experimental Study Of Three-Component Down-Hole Tem For Detecting Water-Filled Goaf, Yao Weihua, Wang Peng, Li Mingxing, Su Chao, Cheng Siyuan
Coal Geology & Exploration
The borehole geophysical prospecting method is a research hotspot in recent years. Considering that the down-hole transient electromagnetic method used in metal mines has the characteristics of long radial detection distance and less susceptible to surface electromagnetic interference, it is applied to the exploration of water-filled goaf in coal mines. Three-dimensional finite-difference time-domain(FDTD) algorithm is used to simulate the total field response and abnormal response of the goaf model with different orientations of boreholes. The total field three-component could reflect the water-filled goaf obviously, and the abnormal field three-component shape combination can distinguish the azimuth of the abnormal body. Based …
Fractal Characteristics Of Pores And Microfractures Of Coals With Different Structure And Their Effect On Permeability, Ye Zhenni, Hou Enke, Duan Zhonghui, Wen Qiang, Huang Meitao, He Dan
Fractal Characteristics Of Pores And Microfractures Of Coals With Different Structure And Their Effect On Permeability, Ye Zhenni, Hou Enke, Duan Zhonghui, Wen Qiang, Huang Meitao, He Dan
Coal Geology & Exploration
The characteristics of pores and fractures in coal are the basis to study permeability. In this study, the micro-pores and fractures of coal samples with different structure taken from Guojiahe coal mine were analyzed using mercury injection experiment and scanning electron microscope. The micro-pores and fractures of intact coal and cataclastic coal samples were quantitatively analyzed by using Menger sponge and box-counting dimension. The comprehensive fractal dimension was calculated by pore volume weights. Based on fractal theory, the relationship between fractal dimension of coal samples and coal permeability have been discussed. The results show that brittle deformation adds complexity of …
The Discovery And Geological Significance Of Coal-Formed Graphite In Chongyi Coal Mine In Jiangxi Province, Li Yang, Wang Lu, Cao Daiyong, Du Xin, Zhao Meng, Liu Liming, Wei Yingchun
The Discovery And Geological Significance Of Coal-Formed Graphite In Chongyi Coal Mine In Jiangxi Province, Li Yang, Wang Lu, Cao Daiyong, Du Xin, Zhao Meng, Liu Liming, Wei Yingchun
Coal Geology & Exploration
In order to study the characteristics of coal-formed graphite in Chongyi mine, Jiangxi Province, the coal in Laoshan Section of Upper Permian Longtan Formation in Chongyi mining area was tested and analyzed by means of optical microscope, X-ray diffraction(XRD), Raman spectroscopy and HRTED. The test results showed that the graphitization maceral could be observed under the optical microscope. The XRD diffraction pattern showed a graphite diffraction peak of d002, and the Raman spectrum showed a characteristic peak of graphite(G peak) with sharp peak shape. Multilayer ordered structure of carbon layer was observed by high resolution transmission electron microscope, …
Evaluation Method Of Compressibility Of Shale Gas Reservoir In Consideration Of The Influence Of Fracture Toughness, Zhang Chenqing, Xu Jiang, Peng Shoujian, Yan Fazhi, Wu Bin, Yue Yuqing
Evaluation Method Of Compressibility Of Shale Gas Reservoir In Consideration Of The Influence Of Fracture Toughness, Zhang Chenqing, Xu Jiang, Peng Shoujian, Yan Fazhi, Wu Bin, Yue Yuqing
Coal Geology & Exploration
Compressibility is an important basis for measuring the response of shale gas reservoirs to hydraulic fracturing. Currently, the brittleness index commonly used for shale compressibility has been evaluated. However, in practice, there are problems in which the brittleness index is similar and the actual fracturing effect is far different. In order to make up for the lack of brittleness index for the evaluation of compressibility of shale gas reservoirs, this study incorporated critical mechanical energy release rate in consideration of the influence of fracture toughness, and defined the average critical mechanical energy release rate of the integrated modes I and …
Test Of The Influence Of Dynamic Water Grouting Diffusion Radius Of Fractures In Rock, Gu Shuancheng, Sun Guanlin, Su Peili, Li Jinhua
Test Of The Influence Of Dynamic Water Grouting Diffusion Radius Of Fractures In Rock, Gu Shuancheng, Sun Guanlin, Su Peili, Li Jinhua
Coal Geology & Exploration
Water-cement ratio and grouting pressure are the key factors in the design of hydrodynamic grouting. In this paper, based on the self-designed simulated fissure hydrodynamic grouting indoor test platform, the dynamic water grouting test was carried out, the diffusion mode of the slurry in fractures was discussed. The relationship among the diffusion radius of pure cement slurry, the grouting pressure and water-cement ratio was analyzed. The experimental results were verified by computational fluid dynamics software. The results show that the diffusion mode of the slurry is partition diffusion. When the grouting pressure is constant, the diffusion radius is inversely proportional …
Lbfgs Csamt 1d Inversion Of Limited Memory Based On Boundary Constraint And Its Application, Tang Chuanzhang, Cheng Jianzhong, Yan Liangjun, Feng Guangye, Zhou Lei, Xu Fengjiao
Lbfgs Csamt 1d Inversion Of Limited Memory Based On Boundary Constraint And Its Application, Tang Chuanzhang, Cheng Jianzhong, Yan Liangjun, Feng Guangye, Zhou Lei, Xu Fengjiao
Coal Geology & Exploration
CSAMT is characterized by time-consuming calculation and low accuracy. The conventional inversion method has simple boundary processing, needs big memory, it is difficult to have accurate search direction, influencing severely the effect of inversion. In order to achieve rapid and high-precision forward modeling of CSAMT, to improve the boundary processing method, to reduce memory usage, to optimize the searching direction to reduce the times of iterative inversion, LBFGS CSAMT 1D inversion method based on boundary constraint and limited memory was proposed. Firstly in CSAMT forward modeling, double-precision and parallel algorithm was adopted, realizing rapid and high-precision calculation of the horizontal …
Calibration And Experiment Of Mine Electromagnetic Lwd Gamma Logging Tool, Wang Xiaolong, Jiang Bici, Wang Kaibin
Calibration And Experiment Of Mine Electromagnetic Lwd Gamma Logging Tool, Wang Xiaolong, Jiang Bici, Wang Kaibin
Coal Geology & Exploration
In order to effectively identify coal seam, roof and floor, mine electromagnetic LWD gamma logging tool was developed for directional drilling in coal mine. The calibration coefficient of the instrument can be obtained by natural gamma logging scale, and various measurement curves of mine electromagnetic LWD gamma logging tool can be obtained by standard well test and crossing borehole test in coal mine. Through comparing with the gamma curve of standard well and analyzing the geological data of the crossing borehole, the measurement result accuracy of mine electromagnetic LWD gamma logging tool is verified. The application test in underground coal …
Development Of Impact Screw Motor, Wang Siyi, Li Quanxin, Liu Jianlin, Zhao Jiangpeng, Yang Dongdong
Development Of Impact Screw Motor, Wang Siyi, Li Quanxin, Liu Jianlin, Zhao Jiangpeng, Yang Dongdong
Coal Geology & Exploration
Aiming at the problems of low efficiency and high consumption of bits and drilling tools in drilling hard rock with conventional single bend screw motor, an impact screw motor is developed by adding an impact mechanism between the universal shaft of a common screw motor and the drill bit. The impact screw motor has dual functions of impact and orientation. The structure and the working principle of impact mechanism, the design of key components and the characteristics of the impact screw motor are introduced. Laboratory tests were carried out on the φ89 mm impact mechanism, and the peak impact …
Effect Of Nmr Technology-Based Ultrasonic Frequency On Stimulated Cracking Of Coal, Ma Huiteng, Zhai Cheng, Xu Jizhao, Sun Yong
Effect Of Nmr Technology-Based Ultrasonic Frequency On Stimulated Cracking Of Coal, Ma Huiteng, Zhai Cheng, Xu Jizhao, Sun Yong
Coal Geology & Exploration
In order to further study the effect of ultrasonic frequency on the stimulated cracking effect of coal, the paper conducted the crack experiment on the original coal samples by using the ultrasonic generation meter, and measured the coal by using the NMR equipment through analyzing the T2 curve, the changes of pore structure before and after coal sample cracking were deeply studied. The results show that the pore structure of coal can be effectively improved by the ultrasonic wave. After the crack induced by the ultrasonic wave, the pore quantity inside the coal increased and the total porosity, effective …
Advances On Geological-Geochemical Research Of Coal-Type Uranium In China, Zhou Xianqing, Qin Yong, Lu Lu
Advances On Geological-Geochemical Research Of Coal-Type Uranium In China, Zhou Xianqing, Qin Yong, Lu Lu
Coal Geology & Exploration
There is a huge gap in uranium resources in China. Only developing traditional uranium resources is unable to meet the increasing demand in energy and national defense construction. The exploitation and utilization of coal-type uranium resources can relieve the pressure of demand for uranium resources to a certain extent. By summarizing the research results of coal-type uranium in recent years, the ore location, uranium content range, formation time and distribution range of coal-bearing strata of major coal-type uranium deposits in China, and the definition criteria of coal-type uranium are given, which provides a basis for the classification of coal-type uranium …
Structural Optimization And Simulation Analysis Of High Reliability Wire-Line Coring Drilling Tools For Submarine Drilling Rigs, Wang Jialiang, Peng Fenfei, Wan Buyan, Zhou Yun
Structural Optimization And Simulation Analysis Of High Reliability Wire-Line Coring Drilling Tools For Submarine Drilling Rigs, Wang Jialiang, Peng Fenfei, Wan Buyan, Zhou Yun
Coal Geology & Exploration
In order to improve the working reliability of wire-line coring drilling tools used in submarine drilling rigs, based on the particularity of submarine environment, from the aspect of improvement of the single action performance of the single action mechanism and the working reliability of the suspension mechanism, the structural optimization of the single action mechanism was carried out, the numerical simulation analysis of the suspension mechanism was conducted by using ABAQUS simulation. The results show that the improved bearing assembly structure can restrain sea water corrosion, improve the centering effect of arbor and enhance the flexibility of bearing assembly. The …
Study On Slope Stability And The Effect Of Highfill On The Mechanical Properties Of Red Clay Foundation, Gao Shengxiang, Xu Qiang, Ma Hongyu, Wu Shenglin, Wu Kang, Liu Peng, Wu Zehui
Study On Slope Stability And The Effect Of Highfill On The Mechanical Properties Of Red Clay Foundation, Gao Shengxiang, Xu Qiang, Ma Hongyu, Wu Shenglin, Wu Kang, Liu Peng, Wu Zehui
Coal Geology & Exploration
This paper takes a highfill slope in Anning in Yunnan Province as a case, using investigation, monitoring and other methods, on the basis of the distribution characteristics of red clay, the physical and mechanical properties of red clay before and after filling were analyzed, then the stability of slope was studied by numerical simulation software. The results show that the physical and mechanical indexes of the red clay foundation decrease first and then increase before and after the fill project, the stability of the fill slope shows the trend of decrease first and then increase. The ground fissures in the …