Results 11 to 20 of about 359,678 (168)
Shock and Vibration, 2019 By the multidomain modelling method, the vibration of a high-speed punching press was modelled and simulated, and the influence of the hydraulic system on the vibration of the punching press and the protection efficiency of the punching press under the ...
Teng Xu +5 more
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Research on process parameters of directional hydraulic punching considering creep effect in composite coal seam [PDF]
Meikuang AnquanWith the increasing depth of coal mining and the difficulty of gas control in China, the technology of directional hydraulic punching to enhance gas extraction in composite coal seam has been widely promoted and applied.
Yi LIU, Dingqi LI, Yubo CHEN
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Meitian dizhi yu kantanObjective and Method For broken soft and low-permeability coal seams, gas drainage achieved through permeability enhancement and pressure relief by cross-seam hydraulic caving in coal seam floor faces problems including serious borehole collapse in the ...
Ningping YAO +4 more
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Punching shear strength of steel fibre reinforced lightweight concrete slabs. [PDF]
, 1981 One of the problems in slab-column connections is the punching shear failure at over loads. Such failures are sudden and catastrophic, and are undesirable since they do not allow an overall yield mechanism to ...
Theodorakopoulos, Dimitrios D.
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Technology and equipment of preventing gas overrun in drilling operation of outburst coal seam
Meikuang Anquan, 2021 Aiming at the problem of gas gushing hole during the construction of through layer drilling(hydraulic punching), the factors that easily cause gas overrun in the working space during the hydraulic punching operation are analyzed and determined.
HAO Dian, LI Xuechen, WEI Peijin
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Gong-kuang zidonghua, 2020 Current research on hydraulic punching technology seldom considers that pressure relief range of hydraulic punching in inclined coal seam varies with direction and influence of coal seam inclination on the effective radius of hydraulic punching pressure ...
HUA Mingguo, YAO Banghua, LI Jianwei
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Process simulation and application of hydraulic cavitation while drilling technology
Meikuang Anquan, 2022 In improving the efficiency of gas extraction from soft and low permeability coal seams, the traditional hydraulic punching method requires drilling, lifting the auger, lowering the hole-making device, lifting the auger and then lowering the screen pipe
DUAN Heming +4 more
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Application of integrated drilling and stamping technology in gas extraction through layer drilling
Energy Exploration & Exploitation, 2022 In coal mine gas extraction in China, the current hydraulic permeability enhancement measures generally have complex processes, low adaptability, long operation time, and high labor intensity.
Jinxing Song +3 more
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Geofluids, 2022 Owing to the exhaustion of shallow coal resources, deep mining has been occupied in coal mines. Deep buried coal seams are featured by the great ground stress, high gas pressure, and low permeability, which boost the risk of gas disasters and thus ...
Chaojun Fan +4 more
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Simulation of punching and post-punching shear behaviours of RC slab–column connections
, 2021 The punching and post-punching shear behaviours of reinforced concrete (RC) flat plate structures are often studied by using a representative slab–column connection isolated from the parent structure.
Guan, Hong +4 more
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