Gap element method of longitudinal vibration of drill string
نویسنده
چکیده
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 mechanical model of axial vibration for the deep wells. Analyze and calculate the dynamic response of the drill string by adopting the method of three-dimensional dynamic finite element theory improved the Ritz vector method at the same time, present the fatigue limit stress formula of the drill string, and the software has been compiled based on the above model and the theory. Convenient for drilling construction, contemporary, give the effective action of the vibration reduction based on the theory and calculation.
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