关于内外压力对油井管柱轴向力和稳定性影响问题的讨论

Discussion on Effects of Internal and External Pressure on Axial Force and Stability of Pipe String in Oil Wells

文献[1]对A.Lubinski和H.B.Woods等人建立的判别油井管柱稳定性的传统理论提出了不同看法,并认为传统理论的判别方法和公式是错误的。笔者认真学习和研究了文献[1],发现有些说法与历史事实不符,有些说法是对传统理论的误解,还发现文献[1]给出的"真实模型"不够真实,而且理论推导过程中存在着一个明显的漏洞——在计算轴向力时没有计算下端面上的液压力。详细论述了传统理论的历史发展过程,从原理和应用两方面讲述了传统理论的正确性,并对文献[1]推导过程中的明显漏洞进行了分析。分析认为:文献[1]对"虚力"和乌兹模型的否定都是站不住脚的;对传统的油井管柱稳定性判别方法和判别公式的否定也是不正确的。文献[1]不承认"虚力"的存在,因而无法正确处理下端面上的液压力,这是其推导过程中出现偏差的根本原因。

Reference {-1] raised objection to the traditional theory of determining pipe stability estab- lished by A. Lubinski and H. B. Woods etc, and reached the conclusion that the determining method and formulas of traditional theory were improper. Looking into reference[I] carefully, the author found that some wordings of reference[1]are inconsistent with the historical facts and it has some misunderstandings to the traditional theory, the actual model proposed in it is not real enough, and an apparent error exists in the derivation,i, e. the pressure force on the lower end face of the tube has not been included in calculating the axial force. After analyzing the historical development process of the traditional theory, the paper con- firms the correctness of the traditional theory and its application, and analyzes the apparent error in the der- ivation of reference[I]. It is concluded that ~he denying of fictitious force,Woods Model, traditional method and formulas for calculating stability of pipe string in oil wells does not hold water. Not recognizing the ex- istence of fictitious force in reference[1],the hydraulic pressure on the lower end of the pipe would not be nable to be handled correctly, that is the root cause of error in its derivation Process.