非均匀载荷下双层套管的传递系数

TRANSFER COEFFICIENT DUAL CASING UNDER NON-EVEN LOAD

杨斌 张效羽

Yang Bin Zhang Xiaoyu

江汉石油管理局设计院, 湖北潜江 443123 中国石油规划总院, 北京 100083

传递系数是衡量双层组合套管效果的主要指标。由于应力应变关系的复杂性,用理论方法求解非均匀载荷作用下该种套管的传递系数十分困难。文中用有限元方法计算了不同类型非均匀载荷作用下的传递系数,对其变化规律进行了分析。在大量计算结果的基础上,进行了传递系数计算公式的回归分析,给出了椭圆分布载荷作用下传递系数的拟合曲线及回归公式。这些结果弥补了理论分析的不足,为双层组合套管的设计提供了有效的计算依据。计算过程还证实了双层组合套管的一些试验结果,对该种套管的特点有了进一步的认识。在计算均匀载荷作用下传递系数时,文中方法与理论方法的相对误差小于0.6%;在进行曲线拟合时,最大相对误差小于2%。

The transfer coefficient is one of the main indexes used to evaluate the efficiency of dual casing,while it is difficult to obtained Under the non-even load by the theoretical method, due to the complicity of the stress changes The finite element method is proposed in this condition, to calculate the transfer coefficient and and analyze the changing tendency. Based on large amount of calculating results, the regression of the transfer coefficient calculating formula is carried out, and the regression equation, together with the fitting curve under the elliptic distributed load is presented. This is a supplement to the theoretical and provides a calculating foundation for the designing of dual casing. Some of the testing results of the dual casing is verified by calculating using this method, and the characteristics of this type of casing is further identified. When calculating the transfer coefficient under even load, the deviation between this method and the theoretical method is lower than 0.6%, and it is lower than 2% when in curve fitting.

10.3969/j.issn.1000-7393.2001.04.004