The passibility of down-hole tools in buckled tubing is analyzed when the tools are pulled or lowered through the tubing. Therefore,a new concept"local model",which provides a sophisticated description of down-hole tools passage in buckled tubing from local perspective,is proposed to help instruct practical applications. Ac-cording to the constrained geometric relationship between the tubing and down-hole tools,the dimension governing equation is built. By using the governing equation,the maximum tool length and maximum outside diameter are an-alyzed considering the clearance between the tubing and tools and the clearance between the tubing and wellbore. The results show that the buckled tubing configurations have significant effects on the tool passage length,which in-creases with the growth of wavelength,while decreases with the growth of amplitude. This"local model"calcula-tion results can be implemented in the down-hole tool design model to avoid various down-hole accidents.%针对井下工具在屈曲油管内上提和下放作业过程中的通过性问题,提出了一个新的局部模型来重点研究井下工具在屈曲油管内的可通过性.根据井下工具在屈曲油管内刚性通过时的几何限制条件,建立了工具可通过的尺寸控制方程.根据该控制方程,讨论了在斜直井眼内工具通过屈曲油管的最大长度,并推导得出了工具的最大长度、最大外径等计算公式.分析结果显示屈曲油管构型(波长、幅度等)对工具可通过性有重要影响.屈曲油管的角位移幅度越大,工具越不容易通过,而较大的波长和螺距有利于工具的通过.这一局部模型分析结果可以结合到井下工具的设计模型中,以避免各种井下事故的发生.
展开▼
