Defect assessment on pipe transporting a mixture of natural gas and hydrogen

Abstract

Procedure of defect assessment for steel pipes used for hydrogen or mixture of natural gas and hydrogen is proposed. The hydrogen concentration is controlled by a cathodic polarisation method. Fracture toughness for blunt pipe defect such as dent is measured on "roman tile specimen". It can be determined either critical J parameter or critical notch stress intensity factor. Then the defect assessment is made using a notch modified failure assessment diagramme (NMFAD). © Springer Science + Business Media B.V. 2009.