考虑分段流变模式的深井井筒压力精确预测模型  

An Accurate Prediction Model of Wellbore Pressure in Deep Wells Considering Segmental Rheological Patterns

作　　者：柳贡慧[1] 杨宏伟[2] 李军[2] 张更 王文旭 LIU Gonghui;YANG Hongwei;LI Jun;ZHANG Geng;WANG Wenxu(School of Mechanical and Energy Engineering,Beijing University of Technology,Beijing 100124,China;School of Petroleum Engineering,China University of Petroleum(Beijing),Beijing 102249,China)

机构地区：[1]北京工业大学机械与能源工程学院 [2]中国石油大学(北京)石油工程学院

出　　处：《钻采工艺》2024年第2期42-50,共9页Drilling & Production Technology

基　　金：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”(编号:U22B2072);国家自然科学基金联合基金项目“深井复杂地层智能井控井筒压力预测模型与优化控制方法”(编号:52104012)。

摘　　要：超深井、特深井井筒温度和压力分布范围宽,钻井液流变性受超高温超高压影响显著,基于常规流变模式的井筒压力预测误差较大,文章通过开展温度为20~220℃、压力为0.1~200 MPa的水基钻井液和油基钻井液流变性测试实验,提出了不同温度和压力范围内的钻井液分段流变模式优选方法,建立了考虑多因素综合影响的钻井井筒压力精确预测模型。研究结果表明,随着温度和压力的变化,钻井液流变曲线的变化规律不一致,单一流变模式无法完全表征钻井液的流变特性;赫巴流变模式对100℃以下的水基钻井液和140℃以下的油基钻井液的流变性适用性更好,其他温度范围内罗斯流变模式的适用性更好;分段流变模式对井底压力的影响较为明显。将模型的计算结果与实测数据进行对比,发现井底压力预测误差在0.3 MPa以内,立管压力预测误差小于0.6 MPa;相对于油基钻井液,水基钻井液中的井筒压力预测误差更小。研究结果能够为超深井、特深井井筒压力精确预测奠定理论基础。The wellbore temperature and pressure distribution range of deep and ultra-deep wells is wide,the rheology of drilling fluid is also obviously affected by ultra-high temperature and ultra-high pressure,and the prediction error of wellbore pressure based on conventional rheological mode is big.After rheological tests of water-based and oil base drilling fluids with temperatures from 20℃to 220℃and pressures from 0.1 MPa to 200 MPa,a selection method of segmented rheological model of drilling fluid based on different temperature and pressure ranges was proposed,and an accurate prediction model of wellbore pressure considering multiple influences established in this paper.The results show that the variation law of rheological curve of drilling fluid is inconsistent with the variation of temperature and pressure,and a single rheological model cannot fully characterize the rheological properties of drilling fluid.Herschel-Bulkley mode has better applicability to the water-based drilling fluid rheological property below 100℃and oil-based drilling fluid below 140℃,the Ross mode has better applicability in other temperature ranges.The effect of the segmented rheological mode on the bottomhole pressure was obvious.Comparison of the model calculation results with the measured data shows that the prediction error of bottomhole pressure was less than 0.3 MPa,and the prediction error of the standpipe pressure was less than 0.6 MPa.The wellbore pressure prediction error in water-based drilling fluid was smaller than that in oil-based drilling fluid.This study can provide a theoretical analysis method for accurate prediction of wellbore pressure in deep and ultra-deep wells.

关 键 词：深井 分段流变模式 井筒压力 钻井液 

分 类 号：TE254[石油与天然气工程—油气井工程]