水平井泵送桥塞工具串可通过性研究

Research on the passability of pumping bridge plug tool string for horizontal wells

水平井泵送桥塞射孔联作工艺在页岩气、页岩油、致密油等非常规油气储层开发中得到了广泛的应用。该工艺通过水力泵送的方式,把携带有可钻桥塞和多级射孔枪连结成的工具串送到指定位置。由于井眼轨迹、井筒环境复杂,泵送遇阻、遇卡事故时有发生。本文根据水平井泵送桥塞在套管中的空间结构特点和工具串构型对工具串进行针对性简化,明确在一定狗腿度下工具串在弯曲井段中与井筒的几何关系,提出泵送桥塞工具串与管壁接触点确定方法,并分析其在弯曲井段受力弯曲特性,建立可通过性判别准则。根据实际案例,进行包括井眼轨迹、最大狗腿度与管壁内径的影响因素分析,给出泵送工具串配置参数优化方案,以减少井下事故的发生。

The combined operation technology of horizontal well pumping bridge plug perforation has been widely used in the development of unconventional oil and gas reservoirs such as shale gas,shale oil and tight oil.In this process,the toolstring with drillable bridge plug and multistage perforating gun is sent to the designated position by hydraulic pumping.Due to the complexity of wellbore trajectory and wellbore environment,the pumping blocked and stuck occasionally occurs.According to the structural characteristics of the pumping bridge plug tool string for horizontal wells,this paper simplifies the tool string,the rigid geometric relationship between the tool string and the wellbore in the curved well section under a certain dogleg degree is analyzed,the method for determining the contact point between the pumping bridge plug tool string and the pipe wall is proposed,the stress bending characteristics in curved well sections are analysed,and the criteria for passability is established.According to the actual cases,the influencing factors including the well trajectory,the largest dogleg degree and the inner diameter of the pipe wall are analyzed,and the optimized scheme of pumping process parameters is given to reduce the occurrence of downhole accidents.