基于CAESARⅡ的埋地输油管道热煨弯头危险角度及安全防护措施分析

Analysis on dangerous angle and safety protection measures of hot bending elbow on buried oil pipeline based on CAESARⅡ

输油管道危险角度范围的热煨弯头容易产生应力集中,导致弯头失效,因此有必要探讨热煨弯头的危险角度。利用CAESARⅡ软件,采用建立管道与土壤相互作用模型的方法,以阿赛线埋地输油管道增输改造项目为例,对其中埋地热煨弯头进行数值计算,通过模拟分析可知,阿赛线水平和纵向热煨弯头危险角度集中在20°~40°范围内,采用两侧不回填的方式释放管道对弯头的推力效果明显,而调整管道曲率半径对减小弯头应力效果不明显,因此应减少危险角度范围的热煨弯头使用,并采用不回填的方式减小弯头应力。

The hot bending elbow in the range of dangerous angle on oil pipeline is easy to cause stress concentra- tion which may lead to the failure of bend, so it is necessary to explore the dangerous angle of hot bending elbow. By using CAESAR Ⅱ software and adopting the method of establishing the interaction model of pipeline and soil, and taking the throughout increasing transformation project of Arshan-Saihantala buried oil pipeline （ A-S oil pipe- line） as example, numerical calculation was conducted on the buried hot bending elbow. The results showed that the dangerous angles of hot bending elbow in the horizontal and vertical directions of A-S oil pipeline were concen- trated in the range of 20° - 40°. The effect of adopting the non-backfill on the both sides to release the thrust of pipeline on bend was obvious, while that by adjusting the curvature radius of pipeline was not obvious. So the usage of hot bending elbow in the range of dangerous angle should be reduced, and the way of non-backfill should be a- dopted to decrease the stress of elbow.