裂缝地层随钻段塞止漏技术

针对全部循环井浆加入刚性颗粒的随钻防漏技术中由于震动筛使用和井浆性能调控要求的限制,随钻防漏颗粒粒径和浓度不能太大的问题,提出了随钻段塞止漏技术.该技术机理就是通过单独配置高浓度段塞防漏堵漏浆,在出现漏失趋势或已经出现漏失的时候向井内注入一定体积的随钻段塞防漏堵漏浆进行防漏和堵漏.随钻段塞止漏技术使用防漏堵漏颗粒粒径可以较大,浓度也可以较高,因而能够封堵较大开度裂缝的漏失,并可以较好地协调全井浆加入刚性颗粒进行防漏堵漏的技术限制.现场试验证实了该技术对裂缝性地层的防漏和对地层出现漏失时不停钻堵漏的工艺可行性和良好的止漏效果.随钻段塞止漏技术的成功实施完善和丰富了随钻防漏技术的发展.

Technology of Controlling Loss by Drilling-in Slugging for Fracture Formation

To solve the problem of the preventing agent’s size can’t too big and the concentration can’t too high for the screen shaker’s limit and the drilling fluids’ demands on the process of preventing and controlling loss while drilling for fracture,the drilling-in slugging process technology was proposed.The drilling-in slugging process technology is that the bigger size and higher concentration preventing loss agents was matched on a separate tank,and a selection of drilling-in slugging was pumped into well to prevent and seal mud loss when the formation has a tendency of loss or a loss had been found.The drilling-in slugging loss control agents can seal some big fracture and make up the preventing loss process technology’s disadvantage of entering preventing loss agents into all the circulations for using the bigger size and higher concentration agents.The practice cases have resulted in a good effect on preventing and sealing the fracture loss by using this technology.The success of the drilling-in slugging process and technology has greatly developed and enriched the preventing loss technology while drilling.