控压固井注入阶段井筒压力预测模型  

A Model for Predicting Wellbore Pressure during the Managed Pressure Cementing Injection Stage

作　　者：刘金璐 李军[1] 李辉 杨宏伟[1] 柳贡慧[1] LIU Jinlu;LI Jun;LI Hui;YANG Hongwei;LIU Gonghui(College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing 102249)

机构地区：[1]中国石油大学(北京)石油工程学院,北京102249

出　　处：《钻井液与完井液》2024年第2期231-238,共8页Drilling Fluid & Completion Fluid

基　　金：国家自然科学基金重大科研仪器研制项目“钻井复杂工况井下实时智能识别系统研制”(52227804);国家自然科学基金联合基金项目“特深井复杂温压场测量与井筒压力剖面控制基础研究”(U22B2072);中国石油大学(北京)科研基金(2462023BJRC008)联合资助。

摘　　要：控压固井技术在应对窄密度窗口地层固井难题时具有显著优势,但目前对注入阶段井筒压力的预测模型研究较少。结合控压固井的工艺流程,将注入阶段分为4个环节。基于流变学理论、井筒传热学理论和压力场理论,考虑注入阶段多流体间流变性能的差异,建立了温度-压力-流体性能参数耦合模型,并采用四循环迭代方法进行求解。以X井的控压固井参数为例进行了模拟计算,预测结果误差较小。对控压期间井筒的温度场、压力场和环空ECD进行了分析,研究结果表明,温度场在不同时间段对井口回压的影响规律不同,当环空流体结构为多液柱结构时,井口回压对温度的敏感性较小;井筒压力变化规律受流体位置的分布影响较大;在其他条件不变的情况下,提高注入排量会增加作业密度窗口,但环空最大ECD基本不变。根据研究结果提出了对应的改进思路,以便对控压参数进行更好地设计。Managed pressure cementing(MPC)technology has significant advantages in dealing with cementing challenges in formations with narrow density windows,but there are fewer studies on the prediction model of wellbore pressure during the injection stage.The cement slurry injection stage,based on the process of MPC,is divided into four substages.Based on rheological theory,wellbore heat transfer theory and pressure field theory,a model coupling temperature,pressure and fluid property is established taking into account the differences in the rheology of multiple fluids during the injection stage.The model is solved using four-loop iterative method.Using the parameters from the MPC operation of well X,the model was solved,and the prediction errors are small.Analyses of the temperature field,pressure field and ECD in the annulus during MPC show that the effects of the temperature field on the backpressure at wellhead are different in different time periods;when the fluid column in the annulus is a multi-liquid column,the effects of temperature on the backpressure at wellhead are relatively small.The change of the wellbore pressure is greatly affected by the distribution of fluid position.When other conditions remain constant,increasing injection rate will increase the operating density window,while the maximum ECD in the annulus remains basically unchanged.Corresponding improvement ideas are proposed based on the results for better design of the pressure control parameters.

关 键 词：控压固井 注入阶段 井筒温度 井筒压力 环空ECD 

分 类 号：TE256[石油与天然气工程—油气井工程]