FLOW STRING PRESSURE-TESTING DEVICE Russian patent published in 2007 - IPC E21B17/00 E21B33/12 

FIELD: mining, particularly sealing or packing boreholes or wells.

SUBSTANCE: device comprises hollow body made so that body interior may be sealed. The body has head for fishing tool receiving. Anchoring unit with seat may cooperate with flow string joint in lower section of interval to be pressure-tested. Sealing unit includes sealing means and seating mechanism. Annular isolation means is formed as part of movable hollow body section. Additional seating mechanism seal is arranged from the first isolation means side. Additional seal is sleeve having L-shaped cross-section. Opened sleeve end faces elevated pressure cavity. Gland is installed from another side of annular isolation means. The gland is in contact with fixed section of hollow body arranged in anchoring unit seat. The later is installed at flow string joint. Protective case is installed on fixed hollow body section.

EFFECT: simplified structure and increased reliability.

1 dwg