防砂注汽井节能管柱的研究与应用

Research of Decreasing Wellbore Heat Loss Pipe String Used in Sand Control and Steam Injection Wells

孤岛油田边部稠油单元储层发育差、敏感性强，地层压力下降较快，入井液漏失严重，导致井筒热损失较大，周期液量下降快，生产周期短，油汽比低，热采效果差。针对注汽过程套管存在裸漏段的问题，应用全程密闭注汽管柱设计思路；针对配套工具无密闭注汽、可重复充填功能的问题，优化充填工具结构，增加可配合密封段和井下二次打开装置；针对地层压力低、注汽后漏失冷伤害的问题，优化注汽管柱配套工具，设计防洗井漏失装置。2013～2014年在孤岛油田共实施密闭注汽管柱施工62井次，实施效果较好，大大降低了劳动强度，减少了低温液体漏失对套管的冷伤害，套管使用寿命延长，社会效益明显。

In the heavy oil units on the margin of Gudao Oilfield,reservoir development was poor with strong sensitivity,there existed rapid formation pressure drop,serious fluid leakage.These problems caused grievous wellbore heat loss,periodical fluid falling was fast with short production period,low gas-oil ratio and poor thermal recovery effect.In consideration of the problem of existence of casing leakage in steam injection,the idea of whole and closed steam injection casing string was used.Combined with the problem of no closed steam injection and repeated application of matched tools,the packing tool structure is optimized and a device is added for matching with sealing section and for reopen.In allusion to the problem of low formation pressure and cold damage induced after steam injection,an apparatus for leakage prevention is designed.It has been used in 62 wells in Gudao Oilfield from 2013 to 2014,good application effect is obtained,by which labor intension and the damage of low temperature fluid loss to casing are greatly reduced,it obtains good social effect.