Hydrogen uptake in steel structures can cause a degradation mechanical properties such as toughness, and induce cracks. This phenomenon is widely known hydrogen embrittlement. For structural steels subjected to cathodic protection or pipelines transporting high-pressure gas, embrittlement represents an important challenge. Charpy V-notch testing provides fast inexpensive method for quantifying ...

CTOAC of typical X70, X80 and X90 pipeline steels plates were evaluated by using energy based regression method upon their single specimen. Clear difference in the material resistance to ductile cracking could be distinguished by the values of CTOAC and their characteristic fracture surface. The region of stable cracking on the fracture surface could be identified from the dynamic crack extensi...

in this paper, two api x70 steel pipes (with spiral seam weld) of 56 inch outside diameter and 0.780 inch wall thickness were girth welded first. next, hole drilling tests were conducted for strain measurement on the surfaces of the pipes. the values of residual stresses on the internal and external surfaces of the pipe were determined, from strain data using astm 837 standard. the experimental...