封闭式开窗捞筒打捞器的研制与应用

Development and Application of a Closed Overshot with Slot

在侧钻施工中,当钻井完成后,往往需要对地层进行测井施工,在Φ139.7mm套管内侧钻井钻头外径一般为Φ118mm,测井仪器外径为Φ76mm。由于泥浆配伍性或地层不稳定性,在现场施工中易出现被粘附粘卡等事故,导致测井仪器卡阻无法上提。由于侧钻井一般都采用定向钻井,井眼曲率变化大,使用穿心打捞效果差。室内及现场应用表明,封闭式开窗捞筒操作方便,安全可靠,打捞成功率高。

During the side tracking operation, logging operation will be carried out to the stratum after the drilling is finished. Usually the outside diameter of drilling bit is φ118 mm within an annular tube with inner diameter φ139.7 mm, and the outside diameter of a logging tool is φ76 mm. Because of the mud compatibility or stratum instability, accidents like sticking and blocking easily happened, which resulted in lifting failure of the dpwnhole tools. As mostly the sidetracked well are controlled by drilling with the ferquently changed bore hole curvature , it is undesirable to use the go--through fishing method. Both lab and field applications showed that the closed overshot with slot is safe and convenient to operate and proves a high success rate.