FLOWLINES AND RISERS PIPES ENDS LASER MEASUREMENT FOR ENHANCED GIRTH WELDS MANUFACTURING AND FATIGUE BEHAVIOR

The paper describes the laser pipe end measurement systems developed by Tenaris to perform the automatic dimensional inspection of pipe ends (measuring OD, ID, WT) and the software's applications which analyze the collected data. The measurements performed by the Laser End Measurement System (LEMS) can give great advantages to end users and laying companies allowing a more efficient pipe alignment prior welding. This is of particular importance in offshore oil recovery industry where the fatigue requirements of pipelines subject to high dynamic loads are continuously increasing, as the exploitation is moving in harsh environments. Fatigue is normally the limiting design criterion for products like Steel Catenary Risers (SCRs) or fatigue sensitive flowlines, and it represents its major engineering challenge. One way to minimize the risks of girth welds' fatigue failure is to minimize the pipes abutting Hi-Lo [1,2]. This task could be accomplished by the use of laser pipe ends measurements analyses in conjunction with dedicated software. This paper provides details on the implementation and validation processes of automatic measurement systems (fixed and portable) to determine pipe ends dimensions with precision and repeatability In addition, the features and the capabilities of the fit-for-purpose to the end user automatic applications are showed. These features include the Best Matching (search of the alignments which minimize pipes abutting Hi-Lo), the Counter-Boring (analysis of the best ID/OD to which machine the pipe ends counter-bore and of the forecast of the machined WT after counter boring), and the sorting in families (determination of pipes groups according to their ID/WT/OD tolerances).