大牛地气田双封分层压裂投产管柱研究应用

大牛地气田属低孔、低渗、低压、多层系气藏，部分井单层压裂改造不能满足经济有效开采要求，需要采用双封隔器分压二层，压后不动管柱投产合采。针对液压式封隔器组合分层压裂管柱存在的问题，研究出一套适合大牛地气田分压改造后直接合采投产的井内管柱。该管柱采用机械式封隔器组合，提高了压裂管串的可靠程度，特别是开发出了双滑套喷砂器，在压裂施工结束后不用动管柱而通过双滑套喷砂器实现下部气层与上部气层的连通，满足了压后不动管柱直接投产、二层合采的需要。从2005年至2006年7月，应用该管柱在大牛地气田进行了57口井114层的压裂施工，工具应用成功率达97.0%，取得了显著成效。

STUDY AND APPLICATION OF FRACTURING & PRODUCTION STRING WITH DOUBLE PACKERS IN DANIUDI GASFIELD

Daniudi Gas Field is a low porous, low permeable, low pressure and multizones gas field, single zone fracturing stimulation cannot meet the need of effective production so that a new method has to be used, i.e. fracturing two zones with double packers and putting the both zones into production without moving the string after stimulation. In consideration of the problems existing in separating zones fracturing string with hydraulic packer combination, a string system fitting to Daniudi Gas Field is developed which makes use of mechanical packers combination and puts the fractured zones into production after stimulation, thus the reliability of the fracturing string is enhanced. The prominent point about the combination is the use of double sliding sleeve sand injection valve, which makes the communication between upper zone and lower zone after fracturing treatment, therefore two zones can be produced together without tripping out of the string. From 2005 to 2006, 114 layers of 57 wells in Daniudi Gas Field were treated by using this string combination with a success rate of 97%, remarkable economical effect is achieved.