PACKER Russian patent published in 1996 - IPC

FIELD: oil and gas producing industry; isolation of tubing-casing annulus in operations involved in increase of oil recovery of producing formations. SUBSTANCE: packer has hollow body with radial hole and annular groove. Installed on body is collar and pushing bushing. The latter is located for engagement with collar. Pushing bushing has radial holes and cams which lock pushing bushing in annular groove on the body. Packer has stop sleeve which is connected with body above collar and has hole in wall and forms annular hollow together with body and pushing bushing. Body is movable relative to pushing bushing and its hollow is communicated with ambient medium. This communication is effected above collar through radial hole in body, annular hollow and hole in stop sleeve. EFFECT: higher operate reliability and simplified design. 3 dwg