منابع مشابه
Research on Three-point Centering Device of Cylindrical Drill Pipe
In the process of tightening up and screwing off the iron roughneck, it is required that the center of clamping pliers and the center of drill pipe are coincident, so as to avoid the damage of the circular guide in clamping system, and to ensure the iron roughneck work normally. While the traditional method of centering is artificial in iron roughneck, its precision is low, so it is easy to dam...
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Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on ...
متن کاملاصلاح خطای بهره طبقه تقویت کننده در مبدل آنالوگ به دیجیتال pipe - line به صورت دیجیتالی
چکیده ندارد.
15 صفحه اولThe inertial subrange in turbulent pipe flow: centre line
The inertial subrange scaling of the axial velocity component is examined for the centre line of turbulent pipe flow for Reynolds numbers in the range 249 6 Reλ 6 986. Estimates of the dissipation rate are made by both integration of the one-dimensional dissipation spectrum and the third-order moment of the structure function. In neither case does the non-dimensional dissipation rate asymptote ...
متن کاملGap element method of longitudinal vibration of drill string
Due to the lower tool as the research object to analyze the vibration of the drill string, causes the loss of the low order natural frequency of the drill string and the inherent vibration mode, give rise to the distortion and error of the result from the transient analysis of the drill string. For this purpose, the whole drill string of the deep wells is studied in the article, build the mecha...
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ژورنال
عنوان ژورنال: Doboku Gakkai Ronbunshu
سال: 1984
ISSN: 0289-7806,1882-7187
DOI: 10.2208/jscej.1984.349_144