大尺寸井眼双级注水泥的研究和应用

Research and Application of Two-stage Cementing in Large Size Borehole

随着国内深井超深井的不断增加,在技术套管固井过程中面临着裸眼段长、套管尺寸大、套管下入深、封固段长、水泥浆量大、地层易漏失、水泥浆失重等问题,采用双级注水泥可以解决以上难题。从超大井眼长裸眼段固井面临的难点和双级注水泥分级箍的结构和工作原理出发,针对川东北马深1井存在气层压稳与漏失窗口小、套管尺寸大下入深等固井难题进行了分级箍位置确定、固井方案设计、反挤固井工艺制定和补救措施制定;并结合现场施工对固井质量进行了分析与评价。川东北马深1井Φ339.7 mm技术套管下深4 295 m,分级箍位置2 700.17~2 701.29 m,固井质量优良率达到了92%,为深井超深井的大尺寸双级固井施工提供了宝贵的经验。

With the increase of the deep and super-deep wells,many problems have occurred in the process of intermediate casing cementing such as the long open hole section,the big size of casing,the deep depth of casing setting,the long commenting segment,the large amount of cement slurry,the leakage of stratum,the cement slurry weightlessness and so on. These questions can be solved with the method of two- stage cementing. Based on the difficulties in well cementing caused by the long open hole section of super well,considering the structures and working principles of the two-stage cementing stage collar,problems such as the narrow safety density window,the great size of casing,the deep setting depth and so on are solved. In the well Mashen 1 in the northeastern Sichuan,position of the stage collar is determined,method of cementing is designed,a plan for extrusion cementing is formulated and a remedial measure to solve these questions is made. The Φ339.7 mm intermediate casing of the well Mashen 1 in the northeast of Sichuan was set at the depth of 4 295 m,the stage collar was positioned at 2 700.17 ~2 701.29 m,and the excellent rate of the cementing quality achieve 92%,which provides a valuable experience in the operation of the deep and super-deep wells with large size two-stage cementing.