涪陵页岩气田老区调整井连续管钻塞难点及对策

Analysis of Abnormal Coiled Tubing Plug in Adjustment Wells in Fuling Shale Gas Old Area and Its Countermeasures

涪陵页岩气田焦石坝老区上部气层井和加密井采用密切割新型分段压裂工艺,泵送可溶桥塞射孔联作方式分段压裂。但在压裂后连续管钻磨桥塞作业过程中经常遇到地层出砂、漏失、桥塞碎屑返出率低,造成连续管包裹遇卡、工具遇卡等施工事故。通过对涪陵页岩气田焦石坝老区加密井与上部气层开发井连续管钻塞造成影响的地质、工程因素进行了分析,提出提高连续管钻可溶桥塞提高效率的对策:及时掌握作业井地质情况、优化钻塞工具、优化钻可溶桥塞工艺,可避免复杂事故的发生,达到提速增效的目的。

Upper gas wells and infill wells are the most important part of the stable production in Fuling Shale Gasfield.The pumping bridge plug+perforating method is used for staged fracturing.After the completion of fracturing,coiled tubing with shoes is used to drill and remove the bridge plug in the well,and the well is opened for test and production.Due to the changes in geological factors and fracturing technology during the second development phase,the drilling and grinding of bridge plugs often encounter the abnormal construction situation such as the formation sand production and leakage,bridge plug slip and low return rate of debris during the operation,which is easy to cause construction accidents such as coiled tubing package stuck and tools stuck.In this paper,by analyzing the geological situation of the infill well and the upper gas layer well development,the new staged fracturing technology system and the causes of the complex drilling and grinding bridge plug accident of coiled tubing,the technology suitable for drilling and grinding bridge plug of coiled tubing in horizontal shale gas wells is formed,so as to avoid the occurrence of complex accidents and achieve the purpose of speeding up and increasing efficiency.