METHOD OF PATCHING IN CASING PIPES Russian patent published in 2008 - IPC E21B29/10 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil and gas industry, particularly to equipment and procedure of well capital repair, notably to methods of attaching metallic corrugated and round patches. The method consists in lowering a device assembled with a patch on an instrument into the well, in orientation of the patch to the damage, in generating excessive hydraulic pressure in the system, in expanding the patch with a mandrel head top-down where expanding is facilitated by means of a power-producing pusher with a wellhead arrester which compensates counterweight of the instrument to the power-producing pusher. At implementing the method the lowered instrument is rigidly tied with a wellhead flange; the wellhead arrester is secured to the wellhead flange facilitating its rotation; then progressive motion of the mandrel head and instrument is performed. Rotating motion is communicated to the instrument with a rolling head placed above the mandrel head and connected with a latter with ability to rotate.

EFFECT: upgrading quality of pressurisation, reducing costs and extending scope of repair.

3 dwg