Engineering Critical Assessment for the Flaws in the Pipeline Steel Girth Weld

Abstract:

In the pipeline construction, the girth welds tend to be the weakness because of defects and microstructure. The importance of suitable assessment of various defects in the weld is not only to prevent the cracks from unstable growth to cause catastrophic accident but also can effectively reduce the weld repair to reduce construction cost. Although many welding defects assessment methods and codes are used in this field, there are many differences among them. In this paper, the welding defect assessment methods, such as API 1104 and BS7910, were studied. The results show the key factors that affect the result of these assessment methods. The application of these methods was also discussed. The results indicate that API 1104 level1 has the highest conservatism, while API 1104 level 2 is next.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 881-888
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.881
• Online since: March 2016
• Authors: Jiang Qiao Wu*, Deng Zun Yao, Xin Ran Yuan, Tian Qi Wang, Long Zhang
• Keywords: Defect Assessment, Fracture Toughness, Pipeline Steel, Weld Joints

References

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DOI: 10.1115/ipc2002-27171