Leak Before Break Fracture Assessment for X70 Steel Pressurized Tubes With Axial Surface Crack

Abstract

In oil and gas pipelines, cracks can initiate from regions of high stress concentration or from defects due to either manufacturing or corrosion or both. The cracks under service may grow due to applied load and form stable through-thickness cracks causing leak prior to catastrophic failure. If this leak-before-break (LBB) takes place, then there is a possibility of preventing catastrophic failure. Therefore, LBB analysis is an important requirement for the safe design and re-assessment of pipelines life. This paper presents a simplified approach for the failure assessment utilizing LBB concept of pressurized pipes having an axial crack.