压力管道延性断裂止裂可靠性分析
Reliability Analysis of Crack Arrest in Ductile Fracture of Pressure Pipeline
祁金青 1王莉 1张志平 1肖玖冬 1贺青刚1
作者信息
摘要
为保证压力管道的安全平稳运行,结合正态分布概率密度函数建立了单根钢管止裂概率的计算方法.基于BTC法和CSM公式对管道止裂韧性值进行了修正,在腐蚀速率的影响下考察了整条管道的裂纹止裂可靠性,并分析了不同裂纹扩展范围下的管道失效年限,最后将延性断裂风险和应力失效风险结果进行了对比.结果表明:增大夏比冲击功的均值,可提高单根钢管的止裂概率;在腐蚀速率为 0.38 mm/a时,满足 8根钢管可靠性标准的管道失效年限为 15.2年,满足5根钢管可靠性标准的管道失效年限为15.8年;裂纹延性断裂比应力失效带来的风险更大,应重点关注高腐蚀区域管道的裂纹扩展.该研究可为制管技术指标的制定和在役管道运行的失效分析提供实际参考.
Abstract
In order to ensure the safe and stable operation of pressure pipelines,the calculation meth-od of crack arrest probability of a single steel pipe is established by combining the normal distribution probability density function.The crack arrest toughness value of the pipeline is modified based on the BTC method and the CSM formula.The crack arrest reliability of the whole pipeline is investigated un-der the influence of corrosion rate,and the failure time of the pipeline under different crack expansion ranges is analyzed.Finally,the results of ductile fracture risk and stress failure risk are compared.The re-sults show that the crack arrest probability of a single steel pipe can be improved by increasing the mean value of Charpy impact energy.At a corrosion rate of 0.38 mm/a,the failure life of pipelines that meet the reliability standards for 8 steel pipes is 15.2 years,and the failure life of pipelines that meet the reli-ability standards for 5 steel pipes is 15.8 years.The risk of crack ductile fracture is greater than that of stress failure,and the crack propagation of pipelines in high corrosion areas should be paid more atten-tion.The research can provide a practical reference for the formulation of technical indicators for pipe manufacturing and the failure analysis of in-service pipeline operation.
关键词
压力管道/延性断裂/止裂/可靠性/夏比冲击功/应力失效Key words
pressure pipeline/ductile fracture/crack arrest/reliability/Charpy impact energy/stress failure引用本文复制引用
出版年
2024
NETL
NSTL
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