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Research Status And Prospect Of Drill Pipe Thread Used In Coal Mine, Tian Dongzhuang, Chen Yanyu, Li Qing, Dong Mengmeng, Mou Peiying Aug 2020

Research Status And Prospect Of Drill Pipe Thread Used In Coal Mine, Tian Dongzhuang, Chen Yanyu, Li Qing, Dong Mengmeng, Mou Peiying

Coal Geology & Exploration

Drill pipe is one of the main device for drilling construction of gas drainage, water detection and drainage and geological exploration. Due to complicated force conditions and using environment of drill pipe, accidents in boreholes caused by the failure of drill pipe threads are common. According to different structural classification, the characteristics of drill pipe thread structure in coal mines are introduced in detail; the current research status of thread stress distribution and failure analysis of thread are summarized. The research methods of thread stress distribution mainly include analytical method, finite element method and test method. The main causes of …


Table Of Contents, The Editors Aug 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Layer-Penetrating Staged Fracturing Law Of Horizontal Wells Within Roof Of Coal Seams Under Stress Interference, Xu Yaobo Aug 2020

Layer-Penetrating Staged Fracturing Law Of Horizontal Wells Within Roof Of Coal Seams Under Stress Interference, Xu Yaobo

Coal Geology & Exploration

Layer-penetrating fracturing is the key link to improve production in horizontal well within roof, and stress interference has important influence on layer-penetrating segmental fracturing effect in the horizontal well within roof. Therefore, the layer-penetrating segmental fracturing numerical model of horizontal well within roof is set up, the influence law of fracture propagation on stress interference to layer-penetrating segmental fracturing is studied. The results show that:the rock mechanics parameters, the interval distance and the fracturing construction method are the three important factors affecting the intersegment disturbance of the horizontal well within roof. As the Poisson's ratio of the coal seam goes …


Multi Frequency Perspective Fine Detection Of Radio Wave For Thin Coal Areas In Fully Mechanized Coal Face, Wu Rongxin, Shen Guoqing, Wang Hanqing, Xiao Yulin Aug 2020

Multi Frequency Perspective Fine Detection Of Radio Wave For Thin Coal Areas In Fully Mechanized Coal Face, Wu Rongxin, Shen Guoqing, Wang Hanqing, Xiao Yulin

Coal Geology & Exploration

The large area of thin coal area in the fully mechanized coal mining face is difficult to be detected accurately by the single frequency perspective detection of radio wave, which seriously affects the efficient and safe production of coal face. In order to detect the occurrence of thin coal area more precisely, a method of multi frequency perspective detection of radio wave is put forward. Taking coalface 1610A of Zhangji mine of Huaihe Energy Group as the research object, according to the geological conditions, four frequency(0.088, 0.158, 0.365 and 0.965 MHz) perspective detection are selected to delineate the thin coal …


Development And Application Of Lightweight Underground Drill Rig, Fan Dong, Wang Ruize, Tian Hongliang, Chang Jianghua Aug 2020

Development And Application Of Lightweight Underground Drill Rig, Fan Dong, Wang Ruize, Tian Hongliang, Chang Jianghua

Coal Geology & Exploration

The underground drill rig is too heavy, so it is difficult to move and transport in the roadway with poor conditions. In order to solve the problem, ZDY1200G lightweight underground drill rig with 5052-h38 state high strength aluminum alloy as the main material is developed. The idea of light structure design and modular assembly is adopted, combined with the application of light materials. The maximum weight of single component after quick disassembly of the drill rig is 292.5 kg. The three-dimensional DIC speckle system was used to measure and analyze the strain and displacement of the aluminum alloy feed body …


Summary Of Water Disaster Characteristics And Water Prevention And Control Technology In Open-Pit Coal Mines In China, Huang Xuanming, Zhang Yan, Li Wensong, Tian Zenglin Aug 2020

Summary Of Water Disaster Characteristics And Water Prevention And Control Technology In Open-Pit Coal Mines In China, Huang Xuanming, Zhang Yan, Li Wensong, Tian Zenglin

Coal Geology & Exploration

Opencast mining is one of the two ways of coal mining in China. Similar to the underground coal mine, the open-pit coal mine also faces the problem of water prevention and control in the process of mining. Due to the relatively single type of water disaster in open-pit coal mines in China, domestic scholars have conducted in-depth study on the characteristics of water disaster and water control technology. Based on the distribution of open-pit coal mines in China, this paper analyzes the characteristics of water hazards in open-pit coal mines from three aspects of water filling source, water filling channel …


Water Cutoff Curtain Technology Of Open-Pit Coal Mine Based On Low Strength Impermeable Concrete, Cao Haidong, Miao Hechao, Chi Zan, Gao Sihua Aug 2020

Water Cutoff Curtain Technology Of Open-Pit Coal Mine Based On Low Strength Impermeable Concrete, Cao Haidong, Miao Hechao, Chi Zan, Gao Sihua

Coal Geology & Exploration

The concrete underground continuous wall has the advantages of convenient construction, reliable quality, good impermeability and so on. It is widely used in water conservancy, hydropower, foundation pit support, subway and other impermeability projects. The materials used are both plastic concrete and rigid concrete. In the water-cutting curtain project of an open-pit coal mine in Inner Mongolia, according to its engineering geological and hydrogeological characteristics, a kind of low-strength(8-10 MPa) impermeable(P6 grade) concrete was developed as the wall casting material, which water/cementitious materials ratio is 0.68, sand ratio is 45%, For 1 m3 of concrete, the content of each …


Technology Of High Pressure Jet Grouting Water Cutoff Curtain In Gravel Aquifer, Zhu Mingcheng, Han Qiang, Zhao Guibin, Liu Yuzhu Aug 2020

Technology Of High Pressure Jet Grouting Water Cutoff Curtain In Gravel Aquifer, Zhu Mingcheng, Han Qiang, Zhao Guibin, Liu Yuzhu

Coal Geology & Exploration

The high-pressure jet grouting pile is mainly suitable for the muddy soil, cohesive soil, silt, sand, loess and gravelly soil, but it is seldom used in the gravel stratum or under the dynamic water condition. A water cutoff certain in an open-pit coal mine was constructed by using RJP method, and the high pressure jet grouting technique was successfully applied to gravel aquifer. Based on the pile test and screening test, the influence of gravel layer characteristics on the size of pile diameter was analyzed. The results show that the RJP method had good effect and reliable quality in the …


Properties Of The Occluded Pile Curtain Material Under Low Temperature And Dynamic Water Condition In Deep And Thick Gravel Layer, Peng Wei, Wang Hai, Wang Zhongquan, Bu Guiling Aug 2020

Properties Of The Occluded Pile Curtain Material Under Low Temperature And Dynamic Water Condition In Deep And Thick Gravel Layer, Peng Wei, Wang Hai, Wang Zhongquan, Bu Guiling

Coal Geology & Exploration

In order to reduce the water drainage of the studied open-pit mine, a curtain wall is proposed to cut off the river supply on the north side. With full consideration of the realities of construction site, the occluded pile curtain method is applied in an areas with a high voltage line overhead. The gravel layer thickness of the construction area is 45 m and the permeability coefficient is up to 100 m/d, with 0.033 hydraulic gradient and 5℃ groundwater temperature maintained for a long time. In order to ensure fast pile formation in deep gravel layer and low temperature dynamic …


Inspection Method And Analysis Of The Effect Of Water Cutoff Curtain In Open-Pit Coal Mine, Wang Hai, Peng Wei, Cao Haidong, Wang Li Aug 2020

Inspection Method And Analysis Of The Effect Of Water Cutoff Curtain In Open-Pit Coal Mine, Wang Hai, Peng Wei, Cao Haidong, Wang Li

Coal Geology & Exploration

In order to reduce the water drainage of the studied open-pit mine, a curtain wall was constructed to cut off the river supply on the north side. According to the site construction conditions, four technologies were applied to construct the water cutoff curtain, such as the low-strength impermeable concrete underground continuous wall, HDPE impermeable film, ultra-high pressure angular variable speed jet grouting, and occluding pile. To test the effect of water cutoff curtain in the open-pit coal mine during construction, four surrounding well tests were carried out for three kinds of water cutoff curtain technologies, including low-strength impermeable concrete underground …


Relationship Between Ndvi And Hydromet Factors In Grassland Area Of Open-Pit Coal Mine, Zhang Yan, Huang Xuanming, Chen Shi, Shi Bingxing Aug 2020

Relationship Between Ndvi And Hydromet Factors In Grassland Area Of Open-Pit Coal Mine, Zhang Yan, Huang Xuanming, Chen Shi, Shi Bingxing

Coal Geology & Exploration

The groundwater level of an open-pit coal mine in the grassland area of the east Inner Mongolia has been decreasing continuously under the condition of long-term drainage. In order to study whether the growth of vegetation around the mining area was affected by the decline of groundwater level, the NDVI method was used to analyze the change trend of vegetation index in the study area from 2013 to 2019. Based on the joint entropy theory, the mutual information between NDVI and different meteorological and hydrological elements(temperature, rainfall and groundwater depth)were calculated, and the main influencing factors of vegetation growth were …


Genesis Analysis And Study On Tectonic Control On Water Of Huainan North China-Type Coal Field, Ding Tongfu, Wang Minhua, Zhao Junfeng Aug 2020

Genesis Analysis And Study On Tectonic Control On Water Of Huainan North China-Type Coal Field, Ding Tongfu, Wang Minhua, Zhao Junfeng

Coal Geology & Exploration

In order to analyze deeply the genesis and tectonic control on water of the macrostructures of the fourth stage of the Huainan North China-type coalfield, the forms of folds and faults of the Huainan coalfield were used to verify and compare the North China craton geohistory, stratigraphy, and regional tectonics. Quantitative evaluation of the impact of mining area 8 on production mines was conducted. The results show that the Huainan coalfield was formed by the superposition of the Indosinian, Yanshan and Himalayan movements. The Indosinian movement formed the Huainan coalfield at near-east-west tectonic line(body) in the first stage, and the …


Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong Aug 2020

Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong

Coal Geology & Exploration

In order to restore the sedimentary environment of the Paleogene Yunlong Formation in the Lanping basin, inductively coupled plasma mass spectrometry(ICP-MS) was used to analyze trace elements in 13 samples of gypsum, limestone, gypsum mud, mudstone and sandstone from the Paleogene Yunlong Formation in Lanping Basin. The sedimentary environments and paleoclimate are estimated based on the spider diagram of trace elements in each lithology and the characteristics of the ratio of Cu/Zn, Sr/Cu and Sr/Ba and the content of Sr. The results show that:gypsum, limestone, gypsum mud, mudstone and sandstone are all rich in Rb, Pb, Zr; gypsum and gypsum …


Applicability Of Mercury Injection Test To The Characterization Of Low Rank Coal And Its Correction Method, Liu Yinan, Liu Yong, Xin Fudong, Wei Hongyu Aug 2020

Applicability Of Mercury Injection Test To The Characterization Of Low Rank Coal And Its Correction Method, Liu Yinan, Liu Yong, Xin Fudong, Wei Hongyu

Coal Geology & Exploration

As an effective method for coal reservoir characterization, mercury intrusion has been widely used in reservoir property analysis of medium-high rank coal. However, for low-rank coal, due to its loose and brittle nature, the process of mercury intrusion will destroy the pore structure, resulting in poor applicability of mercury intrusion experiments. In order to accurately assess the damage to the pore structure of low-rank coal by mercury intrusion experiments, lignite and long flame coal were selected as the research objects, and the pore size distribution of coal was tested by mercury intrusion and nuclear magnetic resonance. The results show that …


Biogas Production And Variation Of The Chemical Composition Of The High Temperature Water Extract Of Lignite, Ren Hengxing, He Huan, Liu Fangjing, Wang Meilin, Guo Xin, Chen Linyong, Zhao Han, Yuan Xuefang, Guan Jiadong, Yue Lijiao Aug 2020

Biogas Production And Variation Of The Chemical Composition Of The High Temperature Water Extract Of Lignite, Ren Hengxing, He Huan, Liu Fangjing, Wang Meilin, Guo Xin, Chen Linyong, Zhao Han, Yuan Xuefang, Guan Jiadong, Yue Lijiao

Coal Geology & Exploration

The interaction process between microorganism and coal is complicated. In order to deeply analyze the function and change rule of organic matter in coal in the process of biological gas production, taking Yima lignite and methanogens preserved in laboratory as research objects, the gas production characteristics of water-soluble organic matter of lignite and its chemical composition change before and after gas production were studied. The water-soluble organic components of Yima lignite obtained by deionized water extraction at 70℃ and the extraction residue were used as substrates for biogas production. High performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography(GC) and gas chromatography-mass …


Application Of Controllable Electric Pulse Wave Permeability-Enhancing Technology In The Low-Permeability Coal Seams, An Shigang, Chen Dianfu, Zhang Yongmin, Kong Delei, Li Yang, Zhang Di, Wang Yang Aug 2020

Application Of Controllable Electric Pulse Wave Permeability-Enhancing Technology In The Low-Permeability Coal Seams, An Shigang, Chen Dianfu, Zhang Yongmin, Kong Delei, Li Yang, Zhang Di, Wang Yang

Coal Geology & Exploration

Controllable electric pulse wave permeability-enhancing technology is one of the ideal measures for anti-reflection transformation of low-permeability coal seams. The optimization of construction schemes needs to be solved urgently. Aiming at this problem, in the low-permeability coal seam of Baode coal mine, controllable electric pulse wave permeability-enhancing technology was adopted to optimize the permeability-enhancing construction scheme of the boreholes. Test results show that the controllable electric pulse wave permeability-enhancing effect is the best under the condition of the average permeability-enhancing section of 131 m, the impact density of 0.5 times/m and the average daily extraction volume in an anti-reflection borehole …


Geochemical Characteristics And Their Origin Of Cbm In Xingxian Area, Ordos Basin, Wang Xiangye, Sun Baoping Aug 2020

Geochemical Characteristics And Their Origin Of Cbm In Xingxian Area, Ordos Basin, Wang Xiangye, Sun Baoping

Coal Geology & Exploration

The distribution of carbon and hydrogen isotope of methane is of signification in revealing the origin, the distribution of CBM reservoir, and the source evaluation of CBM. To study the origins of coalbed methane and carbon dioxide, the data of the components、carbon and hydrogen isotopes of CBM from the desorption gas of coal core from Xingxian area were analyzed. With the CBM origins chart board, and the geological environment, the geological effect of the formation and the evolution of CBM were analyzed. the ratios of CBM with different origins were estimated. The results show that the δ13C, values …


Corrosion And Degradation Of Feldspar Sandstone In Acidic Environment, Zhou Bin, Zhang Dongming, Xu Jiang, Cheng Liang, Li Jiaxin Aug 2020

Corrosion And Degradation Of Feldspar Sandstone In Acidic Environment, Zhou Bin, Zhang Dongming, Xu Jiang, Cheng Liang, Li Jiaxin

Coal Geology & Exploration

In order to study the effect of acidic environment on the corrosion and deterioration of rocks, CT images processing technology was used to analyze the meso-composition and structural changes of feldspar sandstone after soaking in acidic water. Shimadzu AGI-250 servo material testing machine was used to carry out uniaxial compression test to observe the deterioration of mechanical parameters. The results show that the total density of the feldspar sandstone decreased Ofter the acidic environment treatment, the distribution trend is homogeneous, and the mineral with higher density is formed in the local area. The secondary pores of the feldspar sandstone increased …


Overburden Failure Simulation Under Double Coal Seams Mining In A Coal Mine In North Shaanxi Province, Sun Xueyang, Zhang Qi, Li Cheng, Zhang Lei Aug 2020

Overburden Failure Simulation Under Double Coal Seams Mining In A Coal Mine In North Shaanxi Province, Sun Xueyang, Zhang Qi, Li Cheng, Zhang Lei

Coal Geology & Exploration

Under the conditions of multi-seam mining, the overburden failure of coal seams has unique characteristics, which affects the mine production arrangement. Taking a mine in northern Shaanxi Province as an example, based on the geological and mining conditions of the mine, the influence of double-seam mining on overburden rock damage was analyzed by using the method of similar material simulation experiment and numerical simulation. The results show that the height of the caving zone and the height of the fractured zone in the overburden of coal seam obtained by using similar material simulation and numerical simulation with different widths of …


Sensitivity Analysis Of Disaster-Pregnant Environmental Factors For Slope Geological Hazards In Kaiyang County, Guizhou Province, Qin Yigen, Yang Genlan, Xie Jin, Liu Bangyu Aug 2020

Sensitivity Analysis Of Disaster-Pregnant Environmental Factors For Slope Geological Hazards In Kaiyang County, Guizhou Province, Qin Yigen, Yang Genlan, Xie Jin, Liu Bangyu

Coal Geology & Exploration

The geological conditions are complex in Kaiyang County, and geological disasters occur frequently. On the basis of field geological hazard investigation, 8 factors including elevation, slope, slope direction, engineering petrofabric, slope structure, fault, drainage and NDVI value are selected as the disaster-pregnant factors of slope geohazards. Based on the GIS platform, and by using the certainty factor model(CF) and the sensitivity-exponential(E), susceptibility of these 8 factors are researched. The results show that the areas with elevation from 515 to 993 m, the slope degree from 20° to 50°, the aspect of the west, the northwest and the southeast, …


Spatial Distribution Of Soil Nutrients In Reclamation Dump Sites Based On Subdivision Idw, Zhao Yanling, Zhao Bincheng, Wang Xin, Xiao Wu, Liu Huifang Aug 2020

Spatial Distribution Of Soil Nutrients In Reclamation Dump Sites Based On Subdivision Idw, Zhao Yanling, Zhao Bincheng, Wang Xin, Xiao Wu, Liu Huifang

Coal Geology & Exploration

Accurately grasping the spatial distribution of soil nutrients is of great significance for evaluating the soil quality of reclamation dumps and formulating corresponding reclamation measures. The general interpolation method of the complex terrain of the dump site has a poor prediction effect. The northern dump of Shengli No.1 open-pit mine in Xilinhot, Inner Mongolia was selected as an example in the paper. The soil nutrients(available nitrogen, available potassium, available phosphorus and organic matter) were spatially interpolated using the inverse distance weighting method based on terrain partitioning, and compared with the conventional inverse distance weighting method and kriging interpolation method. The …


Study On The Effect Of Dual-Freedom Coupling Between The Tilt Geophones And The Surface, Sun Chao, Sun Liang, He Dengke, Tian Siqing Aug 2020

Study On The Effect Of Dual-Freedom Coupling Between The Tilt Geophones And The Surface, Sun Chao, Sun Liang, He Dengke, Tian Siqing

Coal Geology & Exploration

In the process of coalfield seismic data acquisition, there is a situation of repeated geophone layout at the same point. The tilt angle difference of the geophones will leads the change of coupling condition between the geophone and the surface, which affects the quality of seismic data acquisition. In this paper, the tilt angle parameters of geophone were introduced into the coupling system of the geophone and the surface. From the point of view of vibration mechanics, the "vibration system with coupling of the dual degree of freedom" of tilt geophone was deduced. The influences of the tilt angle of …


The High-Resolution Transient Electromagnetic Detection Technology For Ultra-Shallow Layer In Coal Mine, Zhang Jun Aug 2020

The High-Resolution Transient Electromagnetic Detection Technology For Ultra-Shallow Layer In Coal Mine, Zhang Jun

Coal Geology & Exploration

In order to reduce the blind zone of the transient electromagnetic detection in mines and improve the detection accuracy, the high-resolution transient electromagnetic detection technology for the ultra shallow layer in mines is studied. The high-resolution transient electromagnetic detection technology for ultra-shallow layer in mines is not only suitable for conventional mine geological exploration, but also for high-resolution detection of shallow geological bodies such as cracks in the roof of the mine roadway, ensuring the safe and efficient mining. Through theoretical research, the feasibility of the shallow high-resolution transient electromagnetic method in mine was established; the hardware system of the …


Design Of Piezoelectric Effect-Based Energy Recovery Device Wile Drilling, Wu Tianyu, Zheng Jun, Zhang Bo, Chen Yu, Tian Hong, Dou Bin Aug 2020

Design Of Piezoelectric Effect-Based Energy Recovery Device Wile Drilling, Wu Tianyu, Zheng Jun, Zhang Bo, Chen Yu, Tian Hong, Dou Bin

Coal Geology & Exploration

Aiming at the problem of continuous power supply of downhole instruments and the recovery of longitudinal vibration energy of drill pipe in drilling field, a new type of energy recovery device based on positive piezoelectric effect was designed. The radial dimension parameters and piezoelectric materials were designed by field experiences and geological survey reports. The piezoelectric coupling model was established based on the numerical simulation software COMSOL Multiphysics, and the length range and the best installation position of the piezoelectric plate were obtained through forced vibration analysis. Through modal analysis and frequency response research, it is obtained that the natural …


Analysis Of Paleoclimatic Cycles In The Ultra Thick Coal Seam Of Yan'an Formation In The Southern Ordos Basin, Dong Guoqi, Wang Dongdong, Liu Haiyan, Mao Qiang, Yin Lusheng Jun 2020

Analysis Of Paleoclimatic Cycles In The Ultra Thick Coal Seam Of Yan'an Formation In The Southern Ordos Basin, Dong Guoqi, Wang Dongdong, Liu Haiyan, Mao Qiang, Yin Lusheng

Coal Geology & Exploration

Coal is a climate-sensitive sediment that contains abundant paleoclimate information. In order to find out the paleoclimate information contained in the coal seam and the evolution of its controlling factors, the No.4 thick coal seam in the first member of Yan’an Formation in the south of Ordos basin was studied. Based on the intensive sampling of the thick coal seam, the information of organic macerals, major and trace elements, and stable carbon isotopes of organic matter were systematically tested. By using the macerals, characteristic elements and carbon isotopes of coal and rocks, four cycles of paleoclimate with alternation of warm-wet …


Change Law Of Adsorption/Desorption Energy Of Coal With Different Water Content Under The Action Of Far Infrared, Ma Kai, Ma Qianqian, Shi Yongtao Jun 2020

Change Law Of Adsorption/Desorption Energy Of Coal With Different Water Content Under The Action Of Far Infrared, Ma Kai, Ma Qianqian, Shi Yongtao

Coal Geology & Exploration

The essence of coal gas adsorption/desorption process is the process of interaction between gas molecules and molecules or atoms on the surface of the coal matrix, and the nature of the interaction is energy change. In order to deeply study the coalbed gas adsorption/desorption rules and energy change rules under the action of far infrared, the self-developed device was used to perform CO2 adsorption/desorption experiments on coal samples with different water contents under the action of far infrared. Then, the experimental results are calculated using the adsorption/desorption energy change model obtained from the principle of far-infrared thermal radiation, and …


Acoustic Emission Characteristics And Damage Evolution Of Coal-Rock Under Different Confining Pressures, Yu Jie, Liu Xiaohui, Hao Qijun Jun 2020

Acoustic Emission Characteristics And Damage Evolution Of Coal-Rock Under Different Confining Pressures, Yu Jie, Liu Xiaohui, Hao Qijun

Coal Geology & Exploration

Using PCI-2 acoustic emission(AE) system, the AE experiments of different confining pressures (0, 8, 16, 5 MPa) were carried out in Baijiao coal mine in Furong, Sichuan Province, in order to reveal the change rule of ringing count rate, the temporal and spatial distribution of AE, b value of AE and damage characteristics of damaged coal-rock under different confining pressures, and to provide a theoretical basis for prediction of coal-rock damage. The results show that the AE phenomenon can reflect the crack propagation of coal-rock and the confining pressure can restrain the damage of coal-rock. With the increase of confining …


Model-Driven Energy Attenuation Method For Coal Seam Strong Reflection, Zhang Xianxu Jun 2020

Model-Driven Energy Attenuation Method For Coal Seam Strong Reflection, Zhang Xianxu

Coal Geology & Exploration

The reflection of coal seam in seismic data has the characteristics of strong energy, which makes the reflection of adjacent strata often concealed by the reflection of coal seam. This makes it difficult to image the adjacent weak layer and lithological interpretation difficult. Aiming at this problem, a model-driven energy attenuation method for coal seam strong reflection was proposed. This method uses the coal thickness calculated by logging and measured by borehole in underground coal mine to construct cross plot with reflection amplitude of coal seam, and fit the relationship formula between amplitude and thickness. The digital model was constructed …


Influence Of Water Injection In Burst-Prone Coal Seam On Suction And Sticking During Drilling, Hao Zhiyong, Li Zhiwei, Pan Yishan Jun 2020

Influence Of Water Injection In Burst-Prone Coal Seam On Suction And Sticking During Drilling, Hao Zhiyong, Li Zhiwei, Pan Yishan

Coal Geology & Exploration

When the spiral drill pipe is used to predict and evaluate the dynamic disasters such as rock burst, the drilling dynamic phenomena such as suction and sticking are easy to occur. In order to study the influence of water injection in burst-prone coal seam on suction and sticking, the mechanism of dynamic phenomenon of suction and sticking was analyzed by establishing the mechanical model of drill pipe, pointing out that the stress of coal body and the amount of drilling cuttings are the important factors that affect the occurrence of suction and sticking, deriving the calculation formula of drilling mechanical …


Table Of Contents, The Editors Jun 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.