安28断块钻井液技术研究与应用  

Drilling fluid technology for An28 block

作　　者：陈德铭[1] 刘亚元[1] 黄学芳[1] 席凤林[1] 田军[1] 

机构地区：[1]华北石油管理局第一钻井工程公司

出　　处：《钻井液与完井液》2004年第3期34-37,共4页Drilling Fluid & Completion Fluid

摘　　要：安 2 8断块地层承压能力低 ,全井压力形成低 高 低分布 ;地层造浆性强 ,生产用水中钙、镁离子含量高 ,钻井施工难度大 ,井塌、井漏、井喷、压差卡钻等工程事故隐患伴随整个钻井过程 ,在以往钻井过程中 ,经常出现钻井液切力大、触变性强 ,加重引起粘度和切力升高 ,形成加重 排放 再加重的恶性循环。安 2 8断块钻井要求钻井液具有较强的抑制性、一定的抗盐能力 ,良好的流变性能 ,一定的防漏堵漏能力 ,好的润滑防卡性能 ,膨润土含量小于 6 0 g/L ,保证钻井液具有较低的粘度和适宜切力 ,以利于加重作业。通过室内试验研究 ,优选出适应该断块的强抑制封堵型钻井液体系 ,并制定出配套工程措施 ,该套钻井液技术在 1 0口井中成功应用 ,很好地解决了该区块钻井难题 ;钻井液性能稳定 ,起下钻畅通 ,完井电测成功率达到了 1 0 0 % ;钻井周期比以前钻的井缩短了 37.8% ;在三开钻进中出现的几次井漏 ,采用随钻和静止堵漏均取得了满意的效果 ,成功率达 1 0 0 %。In An28 block, the bearing capability of formation is low, and the pressure profile is low high low from upside to down hole. It is difficult to drill in this block, for the strong mud making property of the formation and high concentrations of Ca 2+ and Mg 2+ in industrial water, and engineering accident potentials such as well sloughing, lost circulation, well blowout and pressure differential sticking exist during the whole drilling job. In the past, problems of drilling fluid frequently appeared: high shear value, strong thixotropic property, viscosity and shearing force increasing during weighting process, therefore vicious circle of weighting discharge weighting once more was formed. It is required that the drilling fluid for An28 block should provide excellent inhabitation, some salt tolerance, good rheological behavior, some sloughing preventing and sealing capacity, prominent lubricating ability to avoid pipe sticking, bentonite content less than 60 g/L, low viscosity and proper shear value to make preparation for later weighting job. A strong inhibitive plugging drilling fluid system was optimized based on lab tests, coupled with other engineering measures. The fluid has succeeded in 10 wells, solving drilling problems effectively. The drilling fluid property was stable, trips were smooth and the success percentage of well completing logging was 100% and the drilling period was shortened by 37.8%. In addition, though several lost circulation occurred in the third drilling section, measurements of plugging while drilling and static plugging made satisfied work, with success ratio reaching 100%.

关 键 词：钻井液 抑制性 井眼 承压能力 蒙脱土 地层压力 回收率 pH值 

分 类 号：TE254[石油与天然气工程—油气井工程]