致密油水平井连续油管自适应定向水力喷砂射孔改造技术的应用

Application of Adaptive Directional Hydraulic Sand Blasting Perforation Technology for Coiled Tubing in Tight Oil Horizontal Wells

为解决致密、页岩储层开发中常规螺旋分布炮弹射孔+体积压裂改造过程起裂压力高、易沟通底层或盖层形成无效缝网的问题,结合连续油管水力喷砂射孔技术,提出连续油管自适应定向喷砂射孔填砂分段一体化压裂改造工艺,研发了配套水平井自适应定向装置,并应用于玛湖致密油Ma1井的压裂改造,取得了较好效果。结果表明:一定角度的定向射孔可以诱导水力裂缝沿有益方向延展,通过射孔方位及射孔孔深共同影响裂缝转向半径进而控制有效复杂缝网体积;自主研发水平井自适应定向装置在水平段通过钢球重力感应控制及连续油管泵注实现定向调节,一次入井可多次定向射孔,Ma1井多次定向喷射作业未发生故障,适用性强,可靠性高;全过程通过油管高压射流实现孔内增压、冲蚀孔眼与负压携液三种作用叠加,可降低地层破裂压力、增加孔深、增大转向半径,Ma1井现场实施比常规射孔降低起裂压力26%,日均产量平均最高提高78.4%。研究表明,水力喷射定向射孔可正向诱导形成更多有效复杂缝网从而提高单井产量,有效避免因不当射孔将裂缝快速诱导至底层或盖层形成无效缝网的难题,该技术可为页岩、致密油气资源规模化开发提供一种新的技术思路。

In order to solve the problem of high initiation pressure during the conventional spiral-distributed shell perforation+volume fracturing reformation process in the development of tight and shale reservoirs,the problem of ineffective fracture network formation due to easy communication with the bottom layer or cap layer,combined with coiled tubing hydraulic sandblasting perforation technology,The coiled tubing adaptive directional sandblasting,perforation,and sand filling staged integrated fracturing reconstruction technology was proposed,and a supporting horizontal well adaptive directional device was developed,which was applied to the fracturing reconstruction of Mahu tight oil well Ma1,and achieved good results.The results show that:a certain angle of directional perforation can induce hydraulic fractures to extend in a beneficial direction,and the perforationazimuth and perforation depth jointly affect the fracture turning radius to control the effective complex fracture network volume.Self-developed horizontal well adaptive orientation device is horizontal The section is controlled by steel ball gravity induction and coiled tubing pump injection to achieve directional adjustment.It can be directional perforated multiple times in one well.The multiple directional injection operations of Ma1 well have no failures,strong applicability and high reliability.The entire process is through high-pressure tubing jets The three effects of pressurization in the hole,perforation erosion and liquid carrying under negative pressure are superimposed,which can reduce the formation fracture pressure,increase the hole depth,and increase the turning radius.The on-site implementation of the Ma1 well reduces the initiation pressure by 26%compared with the conventional perforation.The average output increased by 78.4%on average.It is concluded that the hydraulic jet directional perforation can positively induce the formation of more effective complex fracture networks to increase the production of a single well,and effectively avoid the problem of rapid induction of fractures to the bottom or cap layer due to improper perforation to form ineffective fracture networks.It provides a new technical idea for the large-scale development of shale and tight oil and gas resources.