Results 21 to 30 of about 161,873 (336)
On the formation of limit cycle of the friction-induced stick-slip vibration in oilwell drillstring
Petroleum, 2015 In this paper, the stick-slip vibration in oilwell drillstring is studied. The drilling system is modelled as a lumped-parameter torsional pendulum and the interaction between the drill bit and the rock is treated as Coulomb friction.
Xiaohua Zhu, Liping Tang
doaj +1 more source
Machines, 2023 Drill bits with internal cooling capabilities are still not employed in stone machining practices within shop floor environments. Therefore, a conventional industrial drill bit used in stone machining was subject to a redesign wherein an axial cooling ...
Miho Klaić +3 more
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Geofluids, 2022 A swirling drill bit designed with an integrated vane swirler was developed to improve reverse circulation in down-the-hole hammer drilling. Its entrainment effect and influential factors were investigated by CFD simulation and experimental tests.
Cheng Yang +6 more
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The Wear Analysis Model of Drill Bit Cutting Element with Torsion Vibration
Advances in Mechanical Engineering, 2015 Due to some deficiencies in the existing researches of cutting element wear of polycrystalline diamond compact (PDC) drill bit and to reduce the wear rate of cutting element of PDC bit, accurately illustrate the effect of tooth-distributing angle on ...
Jialin Tian +7 more
doaj +1 more source
Full and half-wavelength ultrasonic percussive drills [PDF]
, 2018 Ultrasonic-percussive drills are a leading technology for small rock drilling applications where power and weight-on-bit are at a premium. The concept uses ultrasonic vibrations to excite an oscillatory motion in a free-mass, which then delivers ...
Harkness, Patrick +2 more
core +1 more source
Eos, Transactions American Geophysical Union, 1996 The International Continental Scientific Drilling Program (ICDP) is seeking proposals by January 15, 1997, for its next cycle of scientific projects.Started in February 1996 as a joint program between Germany's GeoForschungsZentrum‐Potsdam, the United States' National Science Foundation (NSF), and China's Ministry of Geology and Mineral Resources, ICDP
openaire +1 more source
Damage assessment of drilled hybrid composite laminates [PDF]
, 2008 Hole drilling operations are common in fibre reinforced plastics - FRP’s - to facilitate fastener assembly to other parts in more complex structures. As these materials are non-homogeneous, drilling causes some damages, like delamination, for example ...
Durão, Luís M. +3 more
core +2 more sources
Research on collaborative optimization of cutting and conveying of separated auger drill
Meitan kexue jishu, 2023 Auger drilling tool is widely used in mining, exploration and security and other fields, is an important part of mine equipment, aiming at the best cutting speed and conveying speed of drill tool mismatch.
Qiang ZHANG +4 more
doaj +1 more source
Impregnated drill bits strengthened by nanoparticles for mineral exploration drilling [PDF]
, 2018 In order to improve the drilling efficiency and service life of impregnated diamond drill bit, WC and ZrO2 nanoparticles were introduced into traditional drill bit matrix.
Baochang, L. +3 more
core
Synchrotron Radiation for Quantum Technology
Advanced Functional Materials, EarlyView.Materials and interfaces underpin quantum technologies, with synchrotron and FEL methods key to understanding and optimizing them. Advances span superconducting and semiconducting qubits, 2D materials, and topological systems, where strain, defects, and interfaces govern performance.
Oliver Rader +10 more
wiley +1 more source