METHOD FOR CASING PIPE REPAIR INSIDE WELL Russian patent published in 2007 - IPC E21B29/10 

FIELD: well drilling and workover, particularly to isolate troublesome zones and leaking casing-pipe sections.

SUBSTANCE: method involves forming inwardly projecting restrictions in end cylindrical parts of profiled shutter; creating outer extensions on installation head and core so that the extensions mate the restrictions; installing shutter and core on the extensions; lowering shutter in leaking section with the use of installation head; expanding profiled parts of shutter by creating hydraulic pressure in the shutter; expanding cylindrical parts and sizing profiled ones by means of core; isolating leaking section located over profiled pipe with the use of tubes having diameters lesser than that of casing pipe to provide axial tube sliding inside casing pipe after hydraulic shutter expansion.

EFFECT: increased quality and reliability.

6 dwg