高温高压深井试油井下管柱力学分析及其应用

MECHANICAL ANALYSIS OF WELL TESTING DOWN-HOLE STRING IN DEEP WELL WITH HTHP AND ITS APPLICATION

分析了高温高压深井试油及其管柱的特点,考虑井身结构、管柱组合、管柱载荷、高温高压及联作等因素,进行管柱轴向屈曲分析,得到了屈曲临界载荷;然后,综合考虑屈曲状态、井口和封隔器的约束,给出了井下管柱载荷、变形、应力计算方法与公式。在此基础上,经多年、数十口井的实践,摸索出了一套实用的试油管柱力学计算步骤、方法,已形成"做法"或"惯例",据此进行管柱力学分析,可以得到实用的结论和可操作的建议。

The paper analyzed the characteristics of production test and well testing string in high temperature and high pressure wells. Based on considering the casing programme, tubing and downhole tools combination, external loads, and influences of high pressure and high temperature, the longitudinal buckling forces of the strings were analyzed, and the buckling critical load was obtained. Then, the computational methods and formulae for calculations of downhole casing load, stress and longitudinal deformations were deduced. With the verification by laboratory and oilfield experiment, a practical calculation process of well testing strings mechanics was formed. Based on the carrying out mechanics analysis, the useful conclusions and operation suggestions were obtained.