FIELD: oil and gas production.
SUBSTANCE: devices designed for repair and/or plugging section of casing consist of mandrel equipped with pumped membrane expanding in radial direction under effect of internal pressure. End zones of the membrane form circular collars tightly pressed to a wall when fluid medium is pumped into a cavity between the mandrel and the membrane. Also, the middle zone of the membrane expands with less amplitude leaving circular space for pumping grout into it. The device is positioned opposite to a treated section; fluid medium is pumped inside the membrane, grout is pumped into circular space; upon cement hardening the membrane is lowered and the device is extracted.
EFFECT: facilitating device passing through smaller diametre of equipment for well completion at cementing lower zone of casing.
13 cl, 15 dwg
