Initial Imperfections of Energy Pipes is of utmost importance while developing numerical models and design guidelines. The effects of initial imperfections should be considered to avoid over estimation of load carrying capacity of pipes. Various methods of taking physical measurements of initial imperfections have been developed previously. These methods are error prone, time consuming, only applicable to short pipe segments, and yield limited number of measured dimensions. The objective of the current study is to devise a more efficient and accurate method for quantifying initial imperfections. A 3D laser scanner is used for fast acquisition of a high density set of points on the pipe surface. Acquired data is then exported to a 3D inspection and reverse engineering software for analysis. Deviation of the pipe diameter is measured with respect to an ideal pipe with constant diameter. Ovalization is measured along the length of the pipe and thickness variation is measured near the pipe edge. Changes in the geometry of the seam weld along the pipe length are also observed. Four different pipe segments were scanned and analyzed. Results of diameter and thickness variations are reported with respect to the location of the seam weld. Diameter variation shows a typical pattern in which the positions of maximum positive and negative deviations of diameter with respect to the seam weld are similar in all the pipes. The high density set of points enables us to arrive at larger volume of measurement results compared to previous methods. Based on this new technique of measurement, it is possible to develop a more accurate and applicable initial imperfections model for energy pipelines.
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