大斜度井分注管柱长效密封与安全起下技术

Long-lasting Sealing and Safe Tripping Technology for Separate Layer Injection String in Highly Deviated Well

为了满足冀东油田大斜度井长期细分注水工艺需求,调研了常规分注管柱在大斜度井中服役存在的问题:下管时锚定器易提前解卡、封隔器封隔有效期短以及起管时易解封失败等。鉴于此,研制了4种配套井下工具和1种分注管柱,包括防提前解卡的锁块式锚定器、保护封隔器胶筒的螺旋扶正器、提高密性能的长效密封封隔器和使分注管柱逐级解封、遇卡丢手的解封连通丢手接头以及大斜度井分注工艺管柱。现场应用结果表明:该技术下管作业成功率100%,封隔器的密封时效大于24个月;起管时管柱能够实现逐级解封、遇卡丢手,小修可完成起管。长效密封与安全起下技术适用于冀东油田大斜度井长期多级分注工艺。

To meet the long-term separate layer water injection demand for highly deviated wells in Jidong Oilfield,the problems of the conventional separate layer injection string in the highly deviated wells were investigated.Four types of supporting downhole tools and one separate layer injection string were developed,that is,anti-premature releasing lock-block type anchor,spiral centralizer protecting packer rubber,long-lasting sealing packers to increase sealing performance,releasing and connecting joint for releasing pipe stuck and separate layer injection string for highly deviated well. Field application showed that the technology allowed a pipe running success rate of100%,a packer sealing time of more than 24 months. When pulling the pipe string out of hole,the pipe string could be released stage-by-stage,and be released when got stuck and then pulled out of hole after workover operation. The long-lasting sealing and safe tripping technology is suitable for the long-term multi-stage separate layer water injection of highly deviated wells in Jidong Oilfield.