新型井下可控套管整形装置的研究

New Controllable Downhole Casing Drift Swage

针对现有套管整形方法的不足,提出了一种新型井下可控套管整形装置,并对装置进行了可控性分析和安全性分析。该装置主要由整形机构和回复机构组成,通过控制地面泵提供的液体压力来控制单次整形量;其工作部件为2个硬质支撑块和整形棱柱,大大增加了整形面积,减小了单个部件的胀形力。分析结果表明,装置通过整形棱柱和硬质支撑块整形,地面泵控压,结构简单,且泵泄压后通过复位弹簧复位;随着地面泵压的增大,套管外壁到内壁的径向应力非均匀性增大,表明整形时需提供合适的压差以控制套管整形径向应力;在不同的工况条件下,整形棱柱和硬质支撑块不会发生塑性变形和剪切失效,满足安全使用要求。

With regard to insufficiency of existing casing drift swages, a new controllable downhole casing drift swage is proposed, and it is analyzed for controllability and safety. This swage mainly consists of repair mecha- nism and recovery mechanism, and controls single repair quantity through controlling liquid pressure provided by ground pump. Its working parts include 2 rigid support blocks and shaping prisms, which greatly increase repair are- a and reduce bulging force of single part. The analysis results show that the swage, with simple structure, realizes repair relying on shaping prism and rigid support block, and controls pressure with ground pump. It can reset through reset spring after pressure relief. With the increasing of ground pump pressure, the radial stress from outer wall to inner wall of casing increases unevenly, this means that it is necessary to provide suitable pressure difference during the repair, so as to control the radial stress of casing drift swage. Under different working conditions, shaping prism and rigid support block will not suffer from plastic deformation or shearing failure, so the swage meets the requirements for safety.