Assessment Methods for the Dented Pipe of Grade X80

  • Qiaofei Sun
  • Lei Guo
  • Dahai Zheng
  • Leilei Wang
  • Yi Liu
Conference paper
Part of the Lecture Notes in Mechanical Engineering book series (LNME)


Dents are common defects in pipeline, and may occur during pipeline construction or in service. The dents may threaten the integrity of pipelines. To guarantee the safety operation, the assessment of plain dents is mainly based on the depth or the strain criterion. This paper reviews the basis of the criteria in different codes and the recent research of plain dents. In addition, comparisons are made between different grades of the steel in terms of mechanical properties. With the increasing grade, the strength and the yield ratio increase, but the plastic property decreases. The average UEL of X80 is only 6.2%. When the strain-based criterion is applied to the X80 pipe with dents, it needs to be demonstrated by engineering analysis.


Plain dents Burst strength Depth-based criterion Strain-based criterion Fatigue life 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Qiaofei Sun
    • 1
  • Lei Guo
    • 2
  • Dahai Zheng
    • 3
  • Leilei Wang
    • 2
  • Yi Liu
    • 2
  1. 1.China Petroleum Pipeline Research Institute Co. Ltd.LangfangChina
  2. 2.Sci-Tech Information CenterPetroChina West to East Gas Pipeline CompanyWuhanChina
  3. 3.Piping DepartmentPetroChina West to East Gas Pipeline CompanyWuhanChina

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