Citation

Shabani H, Goudarzi N, Shabani M. Eng. Failure Anal. 2018; 84: 167-184.

Copyright

(Copyright © 2018, European Structural Integrity Society, Publisher Elsevier Publishing)

DOI

10.1016/j.engfailanal.2017.11.003

PMID

unavailable

Abstract

In the present work, the failure investigation of a 30in. diameter gas transmission pipeline (API 5L X-60 grade steel) has been described. The failure was due to a longitudinal crack developing in the centerline of longitudinal weld joint. Mechanisms and morphology of crack initiation and propagation were studied through different tests including: thickness measurement, chemical composition analysis, metallographic inspection, mechanical property testing, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The experiments resulted to the conclusion that some factors associated with Sulphide Stress Cracking (SSC) and metallurgical defects cause the failure of weld joint pipe. Detailed examination revealed that these factors are inappropriate welding parameters, pitting corrosion on longitudinal weld, and hydrogen permeation to the weld metal.
Keywords: Pipeline transportation

Language: en

Keywords

API 5L X60 grade; Failure analysis; Gas transmission pipeline; Sulphide Stress Cracking