复合套管固井在川西水平井中的应用

针对水平井固井套管下入、居中、清除岩屑床、水泥浆失水及析水等问题，提出在水平段采用筛管、管外封隔器、复合套管固井技术，在川西JS 8H井复合套管固井应用中，较好地解决了水平段以上井段因重力作用，套管紧贴井眼下侧而形成窄环空，导致在注替水泥浆过程中井眼下侧的滤饼及钻井液顶替效率较低，易形成窜槽，影响固井质量等难题。同时还满足了完井、储层保护等的要求。该固井技术在川西水平井中的成功应用，为今后类似的水平井完井方式提供了可借鉴的经验。

Application of compound casing strings to horizontal wells cementing in west Sichuan basin

Due to the problems of casing running, centralization, removal of cuttings beds, water loss of cement slurry, and water separation out of the slurry existed during cementing of horizontal wells, compound casing strings with screen pipes and external casing packers are recommended for cementing of horizontal well bores. This technology has been used in the well JS8H in west Sichuan basin, it has avoided the narrow annulus formed due to gravity at the downside of the horizontal well bore, thus to eliminate the possibility of cakes and low displacement efficiency which may cause channeling and low cementing quality. The application of compound casing string can also meet the requirements of completion and reservoir protection. This successful application will provide valuable experiences for similar completion jobs in horizontal wells in the future.