高温高压条件下钻井液当量静态密度预测模型  

Prediction Model of Equivalent Drilling Fluid Density at High Temperature and High Pressure

作　　者：赵胜英[1] 鄢捷年[1] 王利国[2] 耿娇娇[1] 丁彤伟[3] 苑晓荣[4] 

机构地区：[1]中国石油大学石油工程教育部重点实验室,北京昌平102249 [2]中国石油大学提高采收率中心,北京昌平102249 [3]中国石化国际石油勘探开发有限公司,北京100083 [4]中国石化中原油田分公司勘探开发研究院,河南濮阳457001

出　　处：《石油钻探技术》2009年第3期48-52,共5页Petroleum Drilling Techniques

基　　金：国家自然科学基金项目"理想充填理论与保护油气层暂堵新方法研究"(编号:50574061)的部分研究内容;教育部"长江学者和创新团队发展计划"(编号:IRT0411)资助

摘　　要：高温高压井中,钻井液密度受温度和压力的影响较大,如果按照钻井液地面物性参数来计算井底静压则会产生较大误差,在孔隙压力与破裂压力差值很小的井中,可能会产生井涌、井喷或井漏等井下复杂情况或事故。从井筒温度场的数值模拟入手,首先建立了钻井液循环期间井筒的温度分布模型,然后通过高温高压钻井液密度试验,分析了钻井液的高温高压密度特性,并在试验的基础上建立了高温高压钻井液密度预测模型,在此基础上,用迭代数值计算方法建立了钻井液循环期间当量静态密度预测模型。该模型将循环期间的井筒温度场模型与高温高压钻井液密度预测模型结合起来,计算出的钻井液当量静态密度较为准确。该模型为控压钻井技术提供了理论依据,对于合理控制井下压力、预防井下复杂情况和事故的发生具有指导意义。The effects of pressure and temperature on drilling fluids are considerable at high temperature and high pressure. There is a big error if the static pressure at the bottom hole was calculated with parameters of drilling fluids at stand condition, and kick, blowout or lost circulation may occur in wells with small margins between pore and fracture pressure. This work started with establishing the model for predicting the temperature distribution profile of drilling fluids inside the drill string and in the annulus during circulating, then laboratory tests were conducted and the density property of oil-based drilling fluids was investigated. Based on the test, mathematical model for predicting the density of both oil-based and waterbased drilling fluids has been established, and the correlation coefficients are higher than 0.99. Mathematical models for predicting the equivalent static density of drilling fluid have been established by combining the temperature model during circulating and density model. The Prediction models can provide theoretical basis for managed pressure drilling technology, it is significant to control downhole pressure properly and prevent problems and accidents.

关 键 词：钻井液 高温 高压 当量静态密度 数学模型 回归分析 

分 类 号：TE21[石油与天然气工程—油气井工程]