Predictive crack growth models for pipeline integrity and risk management - phase II

用于管道完整性和风险管理的预测裂纹扩展模型 - 第二阶段

• 批准号: 429697-2011
• 负责人: Chen, Weixing
• 金额: $ 10.85万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=552504
• 关键词: Predictive; crack; growth; models; pipeline

Near-neutral pH Stress Corrosion Cracking (NNpHSCC) represents a substantial cost to Canadian pipeline companies and hence to Canadian consumers. NNpHSCC is controlled from an integrity management point of view by in-line inspection for oil pipelines or by hydrostatic testing for gas pipelines. Either of these techniques provides protection from in-service failures for a number of years and then the process has to be repeated. The testing cycle is particularly troublesome for gas pipelines since only quite large flaws that fail at hydrotest stress are detected by the hydrostatic testing technique. These procedures are also enormously expensive. The re-inspection interval or re-test interval is currently determined based on empirical models, which are rather imprecise. Long term investigation at the University of Alberta has found that the crack growth behavior of pipeline steels in NNpH environments is consistent with that of corrosion-fatigue, and crack growth rate can be correlated with a single term that is incorporated with all possible measurable variables pertinent to crack growth.

近中性pH应力腐蚀开裂（NNpHSCC）对加拿大管道公司和加拿大消费者来说都是一笔巨大的成本。从完整性管理的角度来看，NNpHSCC通过对石油管道进行在线检查或对天然气管道进行流体静力测试来控制。这两种技术中的任何一种都可以在数年内防止在役故障，然后必须重复该过程。对于天然气管道来说，测试周期尤其麻烦，因为水压测试技术只能检测到在水压测试应力下失效的相当大的缺陷。这些手术也非常昂贵。目前的复检间隔或复测间隔是根据经验模型确定的，这是相当不精确的。阿尔伯塔大学的长期研究发现，管道钢在NNpH环境中的裂纹扩展行为与腐蚀疲劳的行为是一致的，并且裂纹扩展速率可以与一个单一的术语相关联，该术语包含了与裂纹扩展相关的所有可能的可测量变量。