摘要
在对CNG储气井现场事故调研的基础上对其失效原因进行了分析。采用法兰连接对套管与封头处的连接进行结构改进,并对连接处的主螺纹进行预紧及操作状态下的受力分析和校验。应用非线性有限元分析软件MSC.MARC对CNG储气井套管接头螺纹进行了有限元分析。对分析结果与实际受力情况的比较表明,有限元分析结果是可靠的,为分析套管和接头螺纹处的受力情况、失效分析及结构改进提供了一种新的思路。指出CNG储气井的失效不仅与疲劳受力有关,更重要的是腐蚀的作用和影响,只有综合考虑腐蚀疲劳,才能对储气井的寿命做出准确可靠的评估。
An investigation of accident of CNG gas storage well was made to analyze on its failure. Flange connection was adopted to improve on the joint structure between casing and head. Main bolt was pre-tightened on the joint and force analysis at operation condition is made, and adjustment was done during test. Non-linear FEA of MSC. MARC was used to do FEA for thread of CNG gas storage tank. The comparison between analysis and actual force applied on shows that the FEA result is reliable and provides a new method to analyze the force applied on the joint of casing and thread, to do failure analysis and structure improvement. It is also put forward that the failure is not only related with fatigue, but related with corrosion. Only the consideration of corrosion fatigue is made, can the reliable evaluation of gas storage well life be made.
出处
《石油矿场机械》
2008年第10期59-63,共5页
Oil Field Equipment
基金
"石油天然气装备"教育部重点实验室基金资助项目(2006STS04)
四川省教育厅自然科学重点实验室专项基金资助项目(2006ZD043)
