固井冲洗液冲洗效率评价方法  

Assessment method for flushing efficiency of flushing liquid in cementing

作　　者：唐世忠[1] 饶富培[1] 吴华[1] 郑丽娜[1] 张学强[1] 

机构地区：[1]中国石油大港油田公司采油工艺研究院

出　　处：《石油钻采工艺》2016年第5期601-605,共5页Oil Drilling & Production Technology

基　　金：中油股份公司重大科技专项"大港油区大油气田勘探开发关键技术研究"的子课题"高效钻完井及油气层保护配套技术研究"(编号:2012E-10)

摘　　要：针对目前固井冲洗效率评价方法在实验重复性、测试准确性等方面存在的不足,研制了一种新的冲洗效率评价的装置及实验方法。利用牛顿流体在2个同轴圆筒之间的环形区域内剪切速率分布规律,通过改变装置中杯体直径、转子转速,使冲洗液对杯体内壁的冲洗剪切速率与现场的冲洗剪切速率相等,测量冲洗前后杯体内壁所挂钻井液的变化量,从而计算得到冲洗效率。利用该方法对在用的3种冲洗液的冲洗效率进行了评价,依据评价结果优选了冲洗液类型,并优化了冲洗液用量。实验结果表明:该方法能够模拟固井施工中冲洗液对井壁的冲洗剪切速率及冲洗时间,在相同实验中冲洗效率结果的变化率控制在5%以内,具有较高的重复性,可以作为冲洗效率对比评价的一种方法。Innovative devices and test methods have been developed for assessment of flushing efficiency to compensate insufficiencies of existing methods in repeatability and accuracy. Newtonian fluids are used to highlight distribution of shearing rates in circular zones between 2 coaxial cylinders. By changing diameters of cylinders and rotation speeds of rotors, shearing rate of flushing liquid on internal wall of cylinders can be matched with the shearing rate on site. According to changes in drilling fluid attached to internal wall of the cylinder before and after flushing, flushing efficiency can be determined effectively. The newly-developed technique has been used to assess flushing efficiencies of three different flushing liquids. In accordance with relevant assessment conclusions, optimal flushing liquid type and volume can be identified. Research results show the innovative method may effectively simulate shearing rate and flushing time of flushing liquid to borehole sidewalls during cementing operation. In the same test, changes in results of flushing efficiency can be controlled within 5%. With relatively high repeatability, the method can be used to assess flushing efficiencies.

关 键 词：固井 冲洗液 冲洗效率 剪切速率 冲洗时间 评价方法 

分 类 号：TE256[石油与天然气工程—油气井工程]