Session: DA-08-02 FFS Involving Piping and Pipelines

Paper Number: 106116

106116 - A Novel Strain-Based Fracture Evaluation Method For Long-Distance Pipeline Girth Weld With The Crack Tip Under Large Scale Yield Condition 

The strain-based failure assessment diagram is an important method to assess the crack defects in the pipeline, especially when the nominal stress of the pipeline exceeds the yield strength of the material. The weld strength matching factor is an important parameter affecting the fracture behavior of the pipeline girth weld, while the traditional strain-based failure assessment diagram method cannot consider the influence of weld strength matching. Given this, a finite element model of the crack driving force for local circumferential cracks on the outer surface of girth welds of pipelines was established by the numerical simulation method. Based on the reference strain calculation method proposed by BS 7910 - 2019, the effect of crack depth, crack length, weld strength matching factor, and pipe yield strength on the assessment accuracy of SBFAD for pipeline girth weld crack was verified. Based on this, the improved method and calculation model of reference strain is proposed, and the weld strength matching is incorporated into the strain-based failure assessment diagram accurately, which improves the application scope and evaluation accuracy of the BS 7910 - 2019 evaluation method. The accuracy of the evaluation method is verified by experimental data. The results provide a reference for the engineering critical assessment of pipeline girth welds and also provide technical support for ensuring the intrinsic safety of high-grade steel pipelines.

Presenting Author: Kai Wu Hefei General Machinery Research Institute Co. Ltd.

Presenting Author Biography: I have long been engaged in strength analysis, reliability evaluation, safety evaluation and integrity management of oil and gas storage and transportation facilities based on basic mechanics theory, numerical simulation technology and data-driven method. I have participated in two national key R & D projects and eight enterprise technology R & D projects, and have published 42 academic papers in this field, including 13 SCI papers, 3 EI papers. In addition, I serve as a reviewer of the SCI journals such as Engineering Failure Analysis, International Journal of Pressure Vessels and Piping. In recent years, I focus on high-grade steel pipeline girth weld fracture failure, geological disasters and pipe-soil interaction of China 's oil and gas storage and transportation safety.

Authors:

Kai Wu Hefei General Machinery Research Institute Co. Ltd.
Jie Dong Hefei General Machinery Research Institute Co. Ltd.
Guangfei Guo Hefei General Machinery Research Institute Co. Ltd.