STRUCTURAL INTEGRITY ASSESSMENT OF A PIPE MADE IN X 52STEEL AND USED FOR TRANSPORT OF A MIXTURE OF NATURALGAS AND HYDROGEN

摘要

Procedure of defect assessment for steel pipes used for hydrogen ormixture of natural gas and hydrogen is proposed. The hydrogen concentration iscontrolled by a cathodic polarisation method. Fracture toughness for blunt pipedefect such as gouge is measured on "roman tile specimen". It can be determinedeither critical J parameter or critical notch stress intensity factor. Then the defectassessment is made using a notch modified failure assessment diagramme(NMFAD.