侧钻井分注选注工具及其配套管柱

SEPARATIVE INJECTION AND SELECTIVE INJECTION TOOLS AND AUXILIARY WORKING STRING IN SIDETRACKING WELL

辽河油田套管损坏现象日益严重,其中套管严重损坏无法修补的油水井只能以打侧钻井的形式加以重新利用。目前侧钻井数量已在1400口以上,但与之配套的分注选注工具及其工艺管柱尚不完善。针对侧钻井的井身结构特点,将传统的热膨胀坐封封隔器改为液压式压缩胶筒坐封的小直径注汽封隔器;参考常规177.8mm井分注阀的结构研制了侧钻井分注阀;针对稠油油藏纵向非均质性严重、吞吐开采时吸汽不均、蒸汽波及效率低、油层纵向动用程度差的问题,设计开发了侧钻井分层注汽工艺管柱和侧钻井选层注汽工艺管柱。经现场应用,新型侧钻井注汽封隔器密封、坐封、解封均十分可靠,避免了卡井现象;侧钻井分注选注管柱的设计较为合理、安全,适用于稠油侧钻井的分注选注。

The problem of casing damage is becoming more and more severe in Liaohe Oilfield, and for those oil and water wells that are so badly damaged and cannot be mended, a new hole is sidetracked from the original borehole, and to date, a total of 1400 sidetracked holes have been drilled; however, the auxiliary separative and selective injection tools and working strings are not well equipped. According to the wellbore profile characteristics of the sidetracked holes, small diameter packer of hydraulic rubber cylinder setting is used to replace the conventional thermal expansion setting packer, and a separative injection valve for the sidetracking well is developed based on the structure that of for the 177.8 mm well. Aimed at solving these problems such as severe longitudinal non-homogeneity in heavy oil reservoir, uneven steam absorption, low efficiency of steam spreading, and poor longitudinal pay zone developing, etc., working strings for separative and selective injection in the sidetracking wells were designed and developed. Field application showed that the new type sidetracking injection packer is very reliable in packing, setting and releasing, no sticking was encountered; the design of separative and selective working string is reasonable and safe, and it is suitable for using in the sidetracked wells for heavy oil production.