Evaluation of Aspect Ratio on Tensile and Compressive Properties of Welded API X70 Steel

Abstract

Pipelines are fabricated by welding and are used for transportation of oil and gas products globally. These joints are prone to surface defects and sometimes deep cracks depending on types of loading they experience while in operation. Hence, it is necessary to understand the effect of defects on mechanical properties of welded pipeline joints for estimation of their service lives. In this study, a numerical approach was used to study the effects of aspect ratio on pipeline steel. Artificial cracks were created on API X70 steel tensile and compression specimens using different aspect ratios. ANSYS 2019 2R was used for modelling and loading of the specimens. Results show that the investigated mechanical properties were not only sensitive to materials type (weld and base) but also to aspect ratio. The maximum stresses obtained for tensile and compression specimens using various aspect ratios were discussed.