GAO Zhehui, SHUAI Jian, ZHANG Sihong. Quantitative safety assessment and tolerance size of pipeline weld defects[J]. Oil & Gas Storage and Transportation, 2015, 34(5): 488-492, 496. DOI: 10.6047/j.issn.1000-8241.2015.05.006
Citation: GAO Zhehui, SHUAI Jian, ZHANG Sihong. Quantitative safety assessment and tolerance size of pipeline weld defects[J]. Oil & Gas Storage and Transportation, 2015, 34(5): 488-492, 496. DOI: 10.6047/j.issn.1000-8241.2015.05.006

Quantitative safety assessment and tolerance size of pipeline weld defects

More Information
  • Author Bio:

    GAO Zhehui, reading master, born in 1989, graduated from China University of Petroleum (Huadong), engineering mechanics, in 2011, engaged in the research of residual strength assessment, failure analysis and integrity management of pipelines. Tel: 13810679473, Email: gaoahu302@163.com

  • Received Date: May 28, 2014
  • Revised Date: February 28, 2015
  • Available Online: August 20, 2023
  • Published Date: February 11, 2015
  • Weld defects can be classified as major potential safety hazards that may negatively impact operation of aged pipelines. And for instance, in an old pipeline, the defects, misalignment and evident surface in its girth weld and spiral weld seams are found. Tensile and fracture toughness tests have been performed for parent materials and weld seams of the pipeline, respectively. Based on these test data and with consideration to basic parameters and operation of these pipelines, FAD has been deployed to perform Class Ⅰ and Class Ⅱ assessments of girth weld and spiral weld defects. In this way, safety margin around defected pipes can be analyzed quantitatively. Through iteration, sizes of allowable surface cracks can be determined. Furthermore, quantitative studies have been performed over crack tolerance sizes of girth weld and spiral welding lines. Relevant research results show that Class ⅠS assessments may underestimate bearing capacity of the pipeline, whereas the crack tolerance size determined through calculation is lower than those determined through Class Ⅱ assessments; under the operating pressure of 4 MPa, spiral weld defects of the pipeline displayed minor safety margin with hazards higher than those of girth weld defects, whereas crack tolerance size around welding lines is lower than that of girth weld; compared with crack length, crack depth displayed even higher impacts to assessment results. Relevant researches may provide solid criterions for acceptance of pipeline defects. In addition, these researches may provide valuable references to rational and scientific assessments of weld seams.
  • [1]
    王珂, 罗金恒, 董保胜, 等. 我国在役油气老管道运行现状[J]. 焊管, 2009, 32(12): 61-65. https://www.cnki.com.cn/Article/CJFDTOTAL-HGZZ200912016.htm
    [2]
    SHIH C F, KUMAR V, GERMAN M D. Studies on the failure assessment diagram using the estimation method and J-controlled crack growth approach[C]. West Conshohocken: Elastic-plastic Fracture: Second Symposium, Volume 2 - Fracture Resistance Cruves and Eingeering Applications, 1983.
    [3]
    British Standards Institution. BS 7910-2005 Guide to methods for assessing the acceptability of flaws in metallic structures[S]. London: The Authority of the Standards Policy and Strategy Committee, 2005.
    [4]
    American Petroleum Institute. API 1104-2007 Welding of pipelines and related facilities[S]. Washington D C: API, 2007.
    [5]
    Ainsworth R A. R6-2001 Assessment of the integrity of structure containing defect[S]. London: British Energy Generation Ltd, 2001.
    [6]
    British Standards Institution. PD 6539-1994 Guide to methods for the assessment of the influence of crack growth on the significance of defects in components operating at high temperatures[S]. London: the Authority of the Standards Policy and Strategy Committee, 1994.
    [7]
    李伟, 郑伟. 对钢质管道对口错边量规定的认识[J]. 石油工程建设, 2009, 35(5): 75-77. https://www.cnki.com.cn/Article/CJFDTOTAL-SYGJ200905033.htm
    [8]
    汪建华, 陆皓. 焊接残余应力形成机制与消除原理若干问题的讨论[J]. 焊接学报, 2002, 23(3): 75-79. https://www.cnki.com.cn/Article/CJFDTOTAL-HJXB200203019.htm
    [9]
    杜志明, 范军政. 安全裕度研究与应用进展[J]. 中国安全科学学报, 2005, 14(6): 6-10. https://www.cnki.com.cn/Article/CJFDTOTAL-ZAQK200406001.htm
    [10]
    孙经先, 刘立山. 非线性算子方程的迭代求解及其应用[J]. 数学物理学报, 1993, 13(3): 141-145. https://www.cnki.com.cn/Article/CJFDTOTAL-SXWX200103014.htm
    [11]
    王雅芬, 李荣光, 冯少广, 等. CFRP修复城市燃气管道焊缝缺陷的可行性[J]. 油气储运, 2012, 31(9): 674-677. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCY201209011.htm
  • Related Articles

    [1]LIU Xiaoqian, LI Yuxing, LI Shunli, YUAN Zhu. Liquid holdup distribution laws and critical inclination angle model of undulating wet gas pipelines[J]. Oil & Gas Storage and Transportation, 2017, 36(2): 177-184. DOI: 10.6047/j.issn.1000-8241.2017.02.009
    [2]Tao Weifang, Liu Xu, Wang Qijing. Study on Loss Constitution and Change Law of Underground Gas Storage[J]. Oil & Gas Storage and Transportation, 2010, 29(4): 258-259. DOI: 10.6047/j.issn.1000-8241.2010.04.005
    [3]NI Lingying. Study on Flow Law of Hydraulic Pipe Cleaning Technology[J]. Oil & Gas Storage and Transportation, 2008, 27(8): 27-27, 38. DOI: 10.6047/j.issn.1000-8241.2008.08.008
    [4]HE Chengcai. Flow Law on Turbulent-Laminar Stratified Flow in Aerating Pipes[J]. Oil & Gas Storage and Transportation, 2005, 24(7): 41-45. DOI: 10.6047/j.issn.1000-8241.2005.07.013
    [5]LIANG Xizhang. On the Basic Laws of Pipeline Construction[J]. Oil & Gas Storage and Transportation, 2003, 22(12): 1-9. DOI: 10.6047/j.issn.1000-8241.2003.12.001
    [6]HE Chengcai. Flowing Laws on Eccentric Annular Pipe Flow[J]. Oil & Gas Storage and Transportation, 2002, 21(11): 25-28. DOI: 10.6047/j.issn.1000-8241.2002.11.006
    [7]Chen Jialiang, Wei Zhaosheng, Chen Taoping. Pressure Drop Calculation of Two Phase Horizontal Flow of Gas-Power Law Liquid[J]. Oil & Gas Storage and Transportation, 1994, 13(3): 34-38,46.
    [8]Chen Jinghui, Zhang Longjiang. Prediction in Plug Flow Pressure Drop of Gas——Non—Newtonian Liquid Being Transported in Pipelines[J]. Oil & Gas Storage and Transportation, 1994, 13(2): 15-18.
    [9]Yang Baojun, . Research on Practical Ratio of Gas Content for the Two-phase Flow of Gas and Power-law Liquid in Horizontal Pipe[J]. Oil & Gas Storage and Transportation, 1991, 10(1): 1-6, 26.
    [10]Zhang Longjiang, . Summing-Up of the Two Phase Flow, Gas and Non-Newtonian Fluid[J]. Oil & Gas Storage and Transportation, 1988, 7(3): 1-7, 16.

Catalog

    Article views PDF downloads Cited by()

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return