FRACTURE ASSESSMENT PROCEDURE OF API 5L GAS PIPE STEELS<
Mohamed Hadj Meliani1,2, Zitouni Azari2, Yuri G. Matvienko3, Abdulrazag Elhoud4, Guy Pluvinage2
1)LPTPM, FSSI, University Hassiba Benbouali of Chlef, Algeria,
2)LaBPS-ENIM, University Paul Verlaine of Metz, France
3)Mechanical Engineering Research Institute of the Russian Academy of Sciences, Moscow, Russia
4)Sinal Equipments Scientific & Didactique, Annaba, Algeria
The fracture assessment procedure of API 5L gas pipe steels is analysed from the viewpoint of notch fracture mechanics. The procedure is determined by the interaction between the material failure curve and the notch driving force. The material failure curves, based on three-parameter fracture criterion of (K-T-A3) are determined by experimental tests for different laboratory specimens. The notch driving force consisted in modelling a real pipe with different geometry with a surface longitudinal notch submitted to internal pressure. The extrapolated points of the notch driving force to the material failure curve showed three critical parameters (Kρ,c - Tef - A3ef,c) of fracture resistance of pipe steels. These values could be applied as an important engineering parameter for structural integrity assessment of pipelines during long-term operation.
Keywords: fracture assessment, material failure curve, notch driving force, API 5L, pipeline