渤海油田侧钻“瘦身井”关键钻完井技术研究与应用

Research and Application of Key Drilling and Completion Technologies for Offshore Sidetracking "Slimming Wells"

老井侧钻是渤海油田老区挖潜上产的重要手段。常规方案是在9-5/8in技术套管内开窗侧钻,形成的8-1/2in井眼中只能下入7in尾管,但面临着7in套管内完井无法进行分层开采的问题。通过开展井眼尺寸和套管结构的优化,海上首次创新使用了一种非标准井身结构,侧钻8-1/2in井眼内下入7-5/8in套管,并研发了一套适用于7-5/8in套管的完井工具和工艺技术,经现场试验取得了成功,对渤海油田非常规套管程序的使用及油田高效开发提供了有力保障。

Old well sidetracking is a main ways of tapping the potential and stimulation in matured wells in Bohai Oilfield. The conventional solution is that the wells were sidetracked in 9-5/8in casing, then an 8-1/2in hole was formed and only down into 7in liner. However, it was faced with the problem that the completion for 7in casing cannot be carried out in separate layers. Through the optimization of borehole size and casing structure, a non-standard casing program was innovatively used for the first time on offshore. A set of completion separation tools and technology suitable for 7-5/8in casing was developed, and successful field test has laid an important foundation for the application of unconventional casing program and the fine and efficient development of offshore oilfield.