扶正器对超深气井油管柱屈曲行为的影响研究

为对苛刻工况中超深气井油管柱的屈曲行为进行完整、定量的研究，针对塔里木油田某超深气井油管柱，采用接触问题的有限元法，建立了原始油管和带扶正器油管2种工况下的有限元模型，并对油管柱的屈曲、接触问题进行模拟。结果表明:2种工况下的油管柱均在中和点到封隔器段发生了非均匀的正弦屈曲，加扶正器油管屈曲后横向位移小，屈曲段变长，屈曲形态有所改善；该模型可以全井段对原始油管柱和带扶正器油管柱屈曲形态进行对比分析，并且可获取原始油管屈曲后与套管的接触压力及其摩擦力，可为扶正器位置设计和油套管摩擦损伤失效分析提供定量数据参考。

Study on influence of centralizer on buckling behavior of tubing string in ultra-deep gas well

In order to study the buckling behavior of tubing string in the ultra-deep gas well under severe conditions completely and quantitatively, aiming at the tubing string of a certain ultra-deep gas well in Tarim oilfield, the finite element models under two types of conditions including the original tubing string and the tubing string with the centralizer were established by using the finite element method of contact problem, then the buckling and contact problems of the tubing string were simulated. The results showed that the non-uniform sinusoidal buckling occurred in the section from the neutral point to the packer for the tubing string under both two conditions. The lateral displacement after the buckling of the tubing string with the centralizer was smaller, the buckling section was longer, and the buckling shape was improved. This model can be used to comparatively analyze the buckling shapes of the original tubing string and the tubing string with the centralizer in the whole well section, and obtain the contact pressure and friction force between the casing and the original tubing after the buckling, so as to provide the quantitative data reference for the design of centralizer position and the failure analysis on the friction damage of the tubing and casing.