PACKER Russian patent published in 2003 - IPC

FIELD: oil and gas producing industry, particularly, means for protection of casing strings from high pressure, mainly, in injection wells. SUBSTANCE: packer has hollow upper and lower mandrels lowered into well on tubing string; expansible branch pipe connected to end of lower mandrel and provided with sealing member in form of flexible shell located on its external surface; core installed on mandrel; and hydraulic chamber. Expansible branch pipe is made with external annular boss above which anchoring section is located with serrations, and, under it, sealing member is provided whose upper part comes in contact with conical surface of annular boss, and its lower end is made in form of dovetail and in compressed state, it is located in sleeve-centralizer secured to end of lower mandrel. Core is made hollow with thickened lower end provided with removable valve, and located in mandrel. Core is made stepped for its wedging with its second step in zone of location of annular boss of expansible branch pipe in its installation. Core hydraulic chamber is formed by upper mandrel, core cavities with valve and tubing. EFFECT: higher operate reliability of packer and reduced consumed time and labor input in its setting. 3 cl, 7 dwg