分层压裂多孔滑套设计与室内试验

Design and Laboratory Test of Multi-hole Sliding Sleeve for Separate Layer Fracture

针对分层压裂采用常规的单孔滑套时，滑套内径受节流压差制约不能进一步缩小，分压层数受限的问题，研制了多孔滑套。该滑套由一个内孔扩展到2～4个孔，增加了分压层数；设计的自定位结构具有强制钢球落入滑套孔内的功能。室内试验结果表明，多孔滑套能实现有效密封。采用该多孔滑套和单孔滑套组合，能够大幅度提高分压层数，为长庆气田多层系井分层压裂提供了技术支撑。

Separate layer fracture adopts conventional single-hole sliding sleeve and thus the inner diameter of the sleeve cannot be further reduced due to the constraint of choke pressure difference and the number of layered fracturing layers is restricted. Therefore, the multi-hole sliding sleeve was developed. The sleeve extended from one inner hole to two to four holes, increasing the number of layered fracturing layers. The designed self-localization structure has the thnction of forcing steel ball to fall into the sleeve. The laboratory test findings show that the multi- hole sliding sleeve can achieve effective sealing. The combination of this multi-hole sleeve and single-hole sleeve can improve the number of layered fracturing layers remarkably, providing the technological support for the separate layer fracture in multiple-layer series wells in Changqing Gasfield.