工程钻井泥浆压力对泥浆失水过程影响实验分析  

EXPERIMENTAL ANALYSIS ON EFFECT OF ENGINEERING DRILLING FLUID PRESSURE TO PROCESS OF FLUID INFILTRATION AND LEAKAGE

作　　者：杨坪[1,2,3] 吴民晖[2] 李天斌[2] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学土木工程学院地下建筑与工程系,上海200092 [3]地质灾害防治与地质环境保护国家重点实验室(成都理工大学),成都610059

出　　处：《工程地质学报》2015年第5期971-975,共5页Journal of Engineering Geology

基　　金：国家自然科学基金项目(No.41002093);上海市自然科学基金项目(No.14ZR1442800);地质灾害防治与地质环境保护国家重点实验室开放基金项目(No.SKLGP2014K013);同济大学青年优秀人才培养计划资助

摘　　要：工程钻进过程中钻井泥浆在井液压力作用下通过孔壁泥皮失水是导致水敏性地层失稳的主要原因。为了深入了解井液失水规律,本文通过改变井液的压力差,对不同井液压力作用下钻井液漏水情况进行了模拟试验研究。实验结果表明:在相同时差内,失水量随井液压力的增大呈现先减小后增大规律;在相同井液压力下,失水的速率随时间逐渐减小,并最终趋于稳定值,失水速率的稳定值与井液压力大小没有明显的相关性;不同井液压力下,随钻井液压力的增大,前期失水量所占的比重增加;形成泥皮的质量随着井液压力的增大而增大。标准失水量随形成泥饼质量的增加呈现先减小后增大的规律。研究成果为钻井泥浆的失水特征评价、失水量的控制提供了参考依据。The infiltration of water through wall cake pore under the effect of fluid pressure is the cause of instability of water sensitive formations during drilling process. In order to better understand the laws of infiltration,infiltration test is conducted under different fluid pressures. The test results show that when infiltration time is the same,the infiltration water increases first and then decreases with increasing of fluid pressure. When fluid pressure is the same,the infiltration rate decreases with increasing of time and eventually tends to a stable value. The stable value of infiltration rate has a low correlation with fluid pressure. When fluid pressure is different,the proportion of previous infiltration volume and the cake mass( under dry conditions) increase with increasing of fluid pressure.Infiltration of water increases first and then decreases with increasing of cake mass. The results of the test can provide reference for evaluation and control of fluid infiltration.

关 键 词：钻井泥浆 井液压力 失水过程 失水量 

分 类 号：P634[天文地球—地质矿产勘探]