底部支撑锚定分注管柱的研究与应用

华北油田注水井具有井眼深、温度高、斜度大等特点,曾经采用不同类型封隔器进行分注,但大部分分注井管柱有效期短,部分井管柱还出现起出困难甚至大修的情况,无法满足油藏分注的要求。通过对常规分注管柱井下受力的分析研究,论证其短寿命原因,提出了分注管柱底部支撑锚定的方式,从根本上解决了深井分注管柱上下蠕动的问题。此外,现有的封隔器用于多级分注时解封负荷过大且易上大修,研制出的新型逐级解封封隔器可以解决常规封隔器下井后的安全起出问题,具有一定的推广价值。

Research and application of layered water injection pipe string anchored by bottom support

The water injection wells in Huabei Oilfield are characterized by great wellbore depth, high temperature, large deviation, etc. Historically, various types of packers were used for layered injection, but the pipestring in most injection wells had a short effective period. Some pipestrings were hard to be tripped out and even repaired. So such pipestrings could not satisfy layered injection into reservoirs. Analysis of downhole stress on conventional layered injection pipestring demonstrated the causes for their short service life and put forward the anchoring mode of bottom support of layered injection pipestrings, which solved the problem of up and down creepage of injection pipestring in deep wells. In addition, the present packers, when used for layered injection, have a large unsetting load and need to be serviced. The new type of stepwise unsetting packers developed lately can solve the problem of safe tripping out of downhole conventional packers and is of some promotion significance.