Results 31 to 40 of about 140,547 (299)
The effects of process parameters on the rock-breaking efficiency of multi-nozzle jet
Journal of Petroleum Science and Engineering, 2021 Abstract This paper examines the effect of multi-nozzle bit on sandstone specimens by means of numerical simulation and experiment, and the rationality is verified. Numerically, the effects of jets with different diameters and angles on rock were simulated by using LS-DYNA, and the rock-breaking shapes of jets with different angles are analyzed ...
Lipeng He +5 more
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Experimental study of the thermal reaming of the borehole by axial plasmatron [PDF]
, 2019 Purpose. To study rock spallation dynamics in the process of the borehole thermal reaming and analyze energy consumption of the borehole thermal reaming process by plasma jets of the axial plasmatron. Methods. Field experimental study of rock spallation
Dhunnoo, N +6 more
core +1 more source
Shiyou jixie, 2021 The research on rock breaking mechanism of special-shaped non-planar PDC cutter is relatively scarce, and the research on domestic prismatic PDC cutter is even scarcer.
Wei Xiuyan +5 more
doaj
Using Concept Maps to Plan an Introductory Structural Geology Course [PDF]
, 2004 This report presents the results of incorporating constructivist methods, including concept maps, into an undergraduate structural geology curriculum. A concept map is a visual representation of concepts and their relationship to each other in a body of ...
core +1 more source
Biosurface and Biotribology, 2021 The purpose of this study is to achieve better understanding of associated mechanisms and to recommend and identify new strategies to develop new rock breaking technology for Tunnel Boring Machines (TBMs).
Jing Zheng +5 more
doaj +1 more source
IOP Conference Series: Earth and Environmental Science, 2021 Abstract Tearing cutters are generally applied to break rocks when shield tunnelling in the strata with large size boulders. To improve rock breaking efficiency, the processes of tearing cutter impacting rock model are simulated, and the effects of cutter mass, impact velocity and spacings on specific energy of rock breaking are studied.
Jinguo Cheng +4 more
openaire +1 more source
On the puzzling feature of the silence of precursory electromagnetic emissions [PDF]
, 2013 It has been suggested that fracture-induced MHz-kHz electromagnetic (EM) emissions, which emerge from a few days up to a few hours before the main seismic shock occurrence permit a real-time monitoring of the damage process during the last stages of ...
Chelidze, T. +2 more
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Rock Breaking Efficiency Analysis of PDC Bit Based on Pointing Angle of Controllable Bent Sub
Shiyou jixie, 2021 In order to improve the rock breaking efficiency of the directional downhole closed-loop controllable bent sub, the ABAQUS software was used to conduct dynamic simulation analysis on the continuous sandstone breaking by the PDC bit under the pressurized ...
Zhang Guangwei +3 more
doaj
New development of efficient rock breaking technology with diamond bit
Jin'gangshi yu moliao moju gongcheng, 2022 Diamond bit is an important tool for drilling. In recent years, with the application of new composite materials and the continuous progress in precision machining technology, combined with the continuous innovation of drilling equipment, diamond bits have achieved rapid development.
Lina SHEN +5 more
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Optimal Radio Window for the Detection of Ultra-High-Energy Cosmic Rays and Neutrinos off the Moon [PDF]
, 2005 When high-energy cosmic rays impinge on a dense dielectric medium, radio waves are produced through the Askaryan effect. We show that at wavelengths comparable to the length of the shower produced by an Ultra-High Energy cosmic ray or neutrino, radio ...
A.G. de Bruyn +53 more
core +6 more sources