Effects of Pre-Strains on Failure Assessment Analysis to API 5L X65 Pipeline

다국어 초록 (Multilingual Abstract)

This paper prescribed the structural integrity of the API 5L X65 pipeline subjected to tensile pre-strain. The effects of pre-strain on the mechanical properties of API 5L X65 pipe were substantially investigated through a variety of the experimental procedures. Axial tensile pre-strain of 1.5, 5 and 10% was applied to plate-type tensile specimens cut from the pipe body prior to mechanical testing. Tensile test revealed that yield strength and tensile strength were increased with increasing tensile pre-strain. The increasing rate of the yield strength owing to the pre-strain is greater than that of the tensile strength. However, the pre-strain up to 5% had a little effect on the decreasing of the fracture toughness. The structural integrity of the API 5L X65 pipeline subjected to large plastic deformation was evaluated through the fitness-for service code.

참고문헌 (Reference)

1 American Petroleum Institute, "Welding of Pipelines and Related Facilities"

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3 American Petroleum Institute, "Specification for Line Pipe"

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6 British Standards Institution, "Guidance on Methods for the Assessing the Acceptability of Flaws in Fusion Welded Structures"

7 British Standards Institution, "Fracture Mechanics Toughness Tests"

8 American Petroleum Institute, "Fitness for Service"

9 Hagiwara, N., "Effects of Pre-Strain on Fracture Toughness and Fatigue-Crack Growth of Line Pipe Steels" 123 : 355-361, 2001