DEVICE FOR SEALING OF WELL TUBING-CASING ANNULUS Russian patent published in 2002 - IPC

FIELD: oil and gas producing industry, particularly, devices for sealing of tubing-casing annulus in separate operation of formations and performance of other operations with packers. SUBSTANCE: device has hollow body. Located on body are sealing member, drive, spring-loaded check valve, and transfer ring. Drive is made in the form of movable and immovable stops Immovable stop is installed above transfer ring for engagement with it. Body and immovable stop have radial holes for communication of drive with body cavity and said annulus above sealing member. Immovable stop is installed above transfer ring. Immovable stop contacting end part is made in the form of internal annular groove for engagement with conical-concave middle part of transfer ring. Movable stop is installed between hollow body and immovable stop and has on its lower end a circular projection for location on it of sealing member. Movable stop contacting surface is in the form of cone with its external circular bead. Connected with stops are rods from material possessing shape memory. Spring-loaded check valve is located concentrically in body. Transfer ring is made in the form of disc spring from flexible deformable metal. Transfer ring is installed with interference fit on immovable stop hub. Transfer ring is conical-concave in section. Places of connection of sealing surfaces are made in the form of annular beads. EFFECT: reliable sealing under conditions of high temperatures and pressures. 2 cl, 4 dwg