DEVICE FOR INSTALLATION OF METAL PATCH IN CASING STRING Russian patent published in 1995 - IPC

FIELD: well work over. SUBSTANCE: device for installation of metal patch in casing string has levers spring-loaded relative to stop and connected with their lower ends to outer surface of stop and guide bushing with projections secured to stop and located under stop. Patch corrugation trough have holes. Lever upper ends are located in corrugation holes of patch and protrusions of guide bushing in patch ridges. Made on body inner surface above anchor is closed recess, and outer surface of shaft has longitudinal grooves. Anchor body is installed for disconnection from shaft and axial motion relative to it, and in the extreme lower position, for communication through shaft longitudinal grooves of chamber between shaft and anchor with well space and location, in this case, of shaft radial channels in place of making closed recess of anchor body. EFFECT: provision of wedging of mandrel head in patch due to patch installation from top down. 3 dwg