DEVICE FOR SUSPENSION AND CEMENTING OF LINER IN WELL WITH PRELIMINARY DISCONNECTION FROM TRANSPORT STRING Russian patent published in 2022 - IPC E21B33/13 

FIELD: construction; oil and gas industry.

SUBSTANCE: invention relates to construction of oil and gas wells, namely to devices for lowering, suspension and cementing of blind strings and liners. Device for lowering of hanger and cementing of liner in well includes unit for disconnection of liner hanger, containing disconnecting sub with lock thread for connection with transportation string in upper part and an external left trapezoidal thread for connection to the housing of the device from below, an anchor-packer assembly consisting of an anchor and a packer installed in the hollow housing of the device, in which a hollow rod with radial holes is also installed. Anchor-packer assembly and the hollow rod form an internal annular cavity of the device, with which the anchor-packer assembly has a hydraulic communication channel. Besides, the device comprises a cementing plug suspension assembly including a suspended cementing plug fixed by means of shear screws in the lower part of the hollow rod, the lower end of which is freely suspended, and the upper end is fixed inside the disconnecting sub. Hollow rod has a hydraulic channel for communication through radial holes with an internal annular cavity of the device, which is hydraulically isolated from above and from below by sealing cups. Cementing plug suspension assembly additionally contains mounting bushing for ball, made with external longitudinal projections conjugated with mating internal slots of suspended cementing plug. Landing bushing and the suspended cementing plug are fixed on the sleeve of the hollow rod independently of each other.

EFFECT: preliminary, before cementing, disconnection of liner from transport string without loss of hydraulic connection with it.

1 cl, 10 dwg