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Pressure drop characteristics of reverse circulation pneumatic cuttings removal during coal seam drilling [PDF]
Science Progress, 2020 To solve the problems that the borehole depth is shallow and the drilling efficiency is low during the gas drainage drilling in soft coal seam with current cuttings removal method, a new technology of reverse circulation pneumatic cuttings removal is ...
Xiaoming Han, Songnan Song, Jialiang Li
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Energy Science & Engineering, 2019 Reverse circulation down‐the‐hole (RC‐DTH) air hammer drilling is a fast and cost‐effective method for hard rock drilling. As the air RC drill bit is the heart for RC‐DTH air hammer drilling system to form the reverse circulation, a large‐diameter RC ...
Xinxin Zhang +3 more
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Nuclear Engineering and Technology, 2020 In a sudden shutdown of primary pump or coolant loss accident in a marine nuclear power plant, the primary flow decreases rapidly in a transition process from forced circulation (FC) to natural circulation (NC), and the lower flow enters the steam ...
Mingrui Li +3 more
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Engineering Applications of Computational Fluid Mechanics, 2022 A feature of reverse circulation pneumatic down-the-hole (DTH) hammer drilling system is its ability to reduce the emission of respirable dust which is known to be harmful to drilling workers and equipment.
Xinxin Zhang +5 more
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Analytical and experimental study of a reverse circulation drill bit with an annular slit
Advances in Mechanical Engineering, 2016 A new type of drill bit designed with an annular slit was developed to enhance the reverse circulation effect of the down-the-hole hammer drilling technology. A computational fluid dynamics code, Fluent, was used to simulate the flow phenomena inside the
Pinlu Cao +4 more
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Design optimization of a coal seam annular air reverse circulation bit
Energy Science & Engineering, 2023 Reverse circulation (RC) drilling technology enables the rapid acquisition of coal seam samples, which is crucial in accurately measuring gas content. In addition, the design of the drill bit plays a key role in RC sampling. In this study, the turbulence
Demin Chen +3 more
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Numerical Simulation Study of a Swirling Drill Bit Used for Ice Core Drilling
Journal of Marine Science and Engineering, 2022 Due to its high mechanical penetration rate and lack of pollution of the environment, air reverse circulation drilling is considered to be a promising method for ice drilling.
Mengke Wang +4 more
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Energy Science & Engineering, 2023 To solve the insufficient energy for reverse circulation fishing tools in complex structure wells, it is necessary to further optimize the design of the tools to improve the impurity salvage efficiency.
Yumei Li +5 more
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Gas reverse circulation drilling technology for large-diameter DTH hammer
Meikuang Anquan, 2023 Large diameter DTH hammer is a drilling tool which has been proved by a lot of engineering practice and can improve the construction efficiency of large diameter drilling on mine surface. However, after drilling into the aquifer, the penetration rate of
ZHAO Jiangpeng
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Meikuang Anquan, 2021 According to the characteristics of shallow depth of collapse column and fault coring borehole in mining face, the hydraulic reverse circulation coring method of horizontal hole is proposed.
ZHAO Jiangpeng
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