对于埋设的高温海管,如果轴向移动被约束,管线中将产生较大的轴向压力,这些压力会使管线产生向上的屈曲,也就是业界常说的“隆起屈曲”。当埋设管线屈曲后可能产生两种情况,一是强度破坏,二是管线伸出泥面,改变原来的设计条件,造成其他形式的破坏。近年来,随着越来越多边际油田的开发,原油的输送温度不断提高,管线的设计温度也就相应提高,因此这种破坏形式有可能成为一种控制工况。介绍了计算隆起屈曲的三种方法,并讨论了各种方法的适用范围。
For buried high temperature subsea pipelines, if the axial movements are restrained, large axial compressive forces will occur and these compressive forces will cause upward buckling (UHB), namely the upheaval buckling. After pipeline buckling occurs, there will be two possible consequences: strength failure, or other type of failure resulting from the deviation from design conditions since the buried pipeline comes out of the seabed. Recently, more and more offshore marginal fields are developed, the transporting temperature rises, and the pipeline design temperature rises accordingly, so the UHB will be probably a critical case. Aiming at this problem, three methods for UHB analysis are presented and the applicable scope is discussed.
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