分段加重法压井过程中立压与套压的变化规律研究

Study on Change Law of Standpipe Pressure and Casing Pressure in Process of Well Control by Subsection Weighting Method

基于司钻法压井循环时间长、套压峰值大和工程师法关井后等待时间长的缺点,在循环加重法的基础上,提出了分段加重法的概念,并根据流体力学基本原理和井控理论,建立了分段加重法压井过程的物理模型,推导出立压和套压的计算公式,且给出压井过程中计算机控制立压的工作原理和过程。通过算例分析,得到了压井过程中立压和套压的变化规律,验证了分段加重法相比于司钻法和工程师法的优越性,为安全、快速、经济钻井提供理论指导。

Due to the existing defects of well killing method, such as the long duration and high peak of casing pressure of driller＇s method and long duration of shut-in of engineer＇s method, the subsection weighting method of well killing is put for- ward on the base of circulating-and-weighting method. According to the principles of fluid mechanics and well control theo- retics, a physical model for the subsection weighting method is established,with the formula for standpipe pressure and cas- ing pressure deduced, as well as the principle and the working process of the computer control of the standpipe pressure in the process of well control are given. The change law of standpipe pressure, casing pressure and the advantage of this method are shown through the case. All these provide the theoretical guidance for safe, fast and economical drilling.