热采侧钻井塑性水泥浆研究与应用

辽河油田稠油热采侧钻井由于其自身的特殊性,如环空间隙小、水泥环薄等,固井质量一直不是很理想,进而导致油井生产寿命短.优选出一种塑性材料,在基浆中加入3%～5%该塑性材料可以将水泥石的变形能力提高8%以上,同时该塑性材料能产生适度弹性膨胀,提高水泥石与套管、地层的封隔性能,可保证水泥环的长期封隔效果.优选出了与该塑性水泥浆配伍的降失水剂、促凝剂、缓凝剂和分散剂,形成了适合不同井温条件的塑性水泥浆配方,该塑性水泥浆的流动性好,失水量可控制在50 mL以下,稠化时间在2～3 h之间可调.该塑性水泥浆在大量热采侧钻井中的现场应用,取得了十分理想的效果.

The Study and Application of Plastic Cement Slurry for Thermal Production Sidetracked Wells

A plastic material was chosen to be used in cement slurry at a concentration of 3～5% in an ef-fort to enhance the deformability (at least 8%) of the set cement. This plastic material also can produce some elastic expansion to improve the sealing between set cement and casing as well as formations. It is ex-pected that the cement job quality can be improved for those thermal production wells producing heavy oil in Liaohe oilfield. These wells have small annular spaces and thin cement sheathes. Other additives used in the cement slurry such as filtration reducer, accelerator, retarder and dispersant were also optimized for use with the plastic material. Cement slurries formulated with these materials can be used in various tem-peratures and their filtration can be controlled below 50 mL. Thickening time can be adjusted between 2～3 hours. This plastic cement slurry has found wide application in thermal production wells.