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Information × Registration Number 0207U008581, 0107U006750 , R & D reports Title Remaining resource estimation methods of the main pipelines welded connections. popup.stage_title Head Andreykiv Olexandr Yevgenovych, Registration Date 18-12-2007 Organization Ivan Franko Lviv National University popup.description2 Report about SRP: 69 p., 24 Fig., 1 tab., 52 sources. Research object: welded joints of oil pipelines Purpose of work - to develop complex approach for estimation the remaining lifetime of the welded joints of pipelines during long exploitation and taking into account the real conditions of work. Research methods - mathematical modelling of fatigue failure of the welded joints and implementation of these models by the method of equivalent areas; method of acoustic emission for detecting defects of the welded joints of main oil pipelines. Two methods are offered in this work. The first is for determining the remaining lifetime of the welded joint of oil pipeline when the sizes of crack-like defects are known, the second - for determining the sizes of these defects. The idea of the first consists in application of energy approach by the performers for constructing the mathematical model to determinate the period of subcritical growth of fatigue crack in the wall of oil pipeline near the circular weld seam. Precision and reliability of this method is tested solving such tasks by the exact numerical Runge-Kut's method. The idea of the second method consists in determination of the mentioned initial sizes of crack-like defects in the wall of pipe near the circular weld seam by the method of acoustic emission. Using earlier developed by authors computer program and parameters of acoustic signals the sizes of defects and the coordinates of their location near the weld seam can be determined. Product Description popup.authors popup.nrat_date 2020-04-02 Close