吐哈油田大间隙、不规则井眼固井技术实践

Cementing Technology Practice of Large Gap and Irregular Borehole in Tuha Oilfield

吐哈油田部分区块存在大间隙、不规则井眼的固井问题,大环空、不规则井段的存在导致顶替效率低,固井施工作业难度大,固井过程中易发生油、气、水窜问题,影响界面胶结质量,进而影响固井质量。针对以上固井难点,通过室内实验研究,对水泥浆配方进行了优化,采取变排量固井工艺和先导浆、聚合物前置液等技术措施,解决了钻井液与水泥浆的相容性差问题,提高了顶替效率,解决了大间隙、不规则井眼固井技术难题,在神泉、三塘湖等区块进行了现场试验,固井质量优质,具有较好的应用推广价值。

There were borehole cementing difl]culties such as large gaps and irregularity in Tuha Oilfield, which results in low disp!.acement efficiency, great difficusity in cementing operation, oil, gas or water breakthrough, so it influences the interface ce- menting quality seriously. In order to solve the above difficulties the laboratory experiment research was made, the performances af cement slurry system was optimized, variable-displacement, pre- flush and polymer pad fluid were used to improve the cementing quality. The compatibility of drilling fluids and cement slurry as well as the displacement efficiency were improved. Large gap and irregular borehole cementing problems were resolved. The field test was carried out in Shenquan Block and Santanghu Block, which showed that the borehole cementing quality achieved high- ly, and has good application and promotion value.