ANNULAR SEAL WITH NON-METALLIC SEAL Russian patent published in 2021 - IPC E21B33/04 

FIELD: mining.

SUBSTANCE: invention relates to a device used in operation of offshore and onshore wells, specifically to an annular seal design with a non-metallic seal, and can be used for sealing annular space between housing of casing hanger and case of column head of conductor. Proposed annular seal with nonmetallic seal for sealing of annular space between housing of column head of conductor and housing of casing string suspension comprises sealing assembly, anchor with blocks, shank and composite housing. Sealing unit consists of annular support, resilient seals arranged in composite housing, composite housing is made of two parts connected to each other by means of axes. Annular support comprises a groove configured to limit movement of the circular support in the composite housing. Composite housing comprises locking ring. At anchor there is one of parts of composite housing, connected to it through locking element. Blocks for fixing the annular seal in the annular groove on the body of the column head of the conductor and in the annular groove on the housing of the casing string suspension are made with possibility of interaction with the shank, the shank is made with a locking element for fixation at the anchor. Lower thrust bearing annular groove is made with possibility to install in it case of medium and arrangement of locking segments. Case of the middle one, containing at least one ring of the spring retainer lower one, is designed so that to enable movement of the bottom thrust relative to the case of the middle one, and at least one groove on the outer and inner sides, in each of which there is at least one ring of the spring retaining upper one. Locking segments are configured to thrust against the grooves on the outer side of the body of the middle. Anchor comprises segmented ledges arranged in segmented grooves of the composite housing and intended for fixation in the radial direction of rings of spring lock upper relative to grooves in the housing medium. Inner and outer parts of composite housing comprise annular ledges, composite housing comprises segmented and closed slots. Anchor contains limiting screws arranged in closed slots of composite body, at that limiting screws serve as locking element, composite body is made with possibility of connection with anchor.

EFFECT: higher reliability of annular seal activation due to fixation of value of compression force required for activation of annular seal, achieved due to limitation of reverse linear displacement of elements compressing annular seal.

4 cl, 2 dwg