Results 21 to 30 of about 19,345 (302)
Effect of forceful suction and air disinfection machines on aerosol removal
BMC Oral Health, 2023 Backgrounds Dental procedures involving drilling and grinding can produce a significant amount of suspended aerosol particles (PM) and bioaerosols. This study aims to analyze the size and concentration of aerosol particles generated during drilling and ...
Yaru Du, Fei Zhao, Ran Tao, Bing Liu
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Calibration of Ultrasonic Transducer Based on Ultrasonic Logging Instrument for Shaft Sinking
Sensors, 2022 High-precision logging equipment is critical for measuring the borehole diameter and drilling offset in coal mining and petroleum drilling. We propose a module composition and positioning principle for an ultrasonic transducer based on an ultrasonic ...
Maoyong Cao +5 more
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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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Meikuang Anquan, 2022 In view of the characteristics of large coal dust production, fast flow rate and high gas content in the air directional drilling of broken soft coal seam, the dust removal device of negative pressure suction and classification purification was designed ...
CHU Zhiwei
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Metals, 2019 Compacted graphite iron (CGI), which is used as a potential material in the auto industry, is a hard-to-machine material for the different minor elements and for the geometry of graphite with grey cast iron.
Yang Li, Wenwu Wu
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Machines, 2021 In this paper, to identify the roof unconfined compressive strength (UCS) in the process of coal mine roadway support in real-time and optimize the real-time drilling speed while drilling, this paper proposes and establishes a drilling test method for ...
Guangdong Yu +4 more
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Impact Characteristics of a Bidirectional Pneumatic DTH Hammer for Unconsolidated Formations
Applied Sciences, 2023 With advantages of high efficiency and low cost, DTH hammer drilling has been highly applied in various drilling projects. When drilling in unconsolidated formations, it is prone to drilling accidents such as drilling tools sticking or burying.
Yuanling Shi, Shuang He, Conghui Li
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Microwave propagation in air drilling [PDF]
Petroleum Science, 2010 This paper examines the feasibility in air drilling of transmitting down-hole signals by using microwaves. Firstly the basic theory of microwave propagation in the drill-pipe or casing was studied, including power loss, cutoff wavelength, and dust scattering.
Xiaofeng Meng +3 more
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Gong-kuang zidonghua, 2018 For problems of shallow gas drainage hole depth, low control precision of drilling trajectory and poor gas drainage effect in soft—fragmentized coal seam of Qinglong Coal Mine, based on the analysis of mine gas geological conditions and existing pre ...
LI Quanxin +3 more
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Evaluation of an air drilling cuttings containment system [PDF]
, 1994 Drilling at hazardous waste sites for environmental remediation or monitoring requires containment of all drilling fluids and cuttings to protect personnel and the environment.
Westmoreland, J.
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