LINER RELEASE DEVICE Russian patent published in 2023 - IPC E21B33/14 

FIELD: liner release device.

SUBSTANCE: liner release device consists of a casing with an upper part including a stuffing box. Inside the lower part of the stuffing box there is a suspension plug on shearable screws with a through passage and a seat for the plug to be dropped from the wellhead. In the lower part of the suspension plug, there is a retaining cone for fitting the plug into the seat of the stop ring. The upper part of the casing consists of a threaded part with the possibility of attaching the device to the transport pipe string. The lower part of the casing consists of an external thread with the possibility of connection with the liner. In the upper part of the stuffing box, above the insulation joints, recesses are made with limiters along the edges, located opposite each other. Movable dies with a protrusion made in the form of a radially bevelled target and pressed against the limiters by springs are installed in the recesses. The lower part of the casing is equipped with at least two through grooves with the possibility of alignment with the movable dies of the stuffing box.

EFFECT: enabling the shank rotation when lowering it into the well and during cementing, increasing the efficiency of liner cementing, possibility of guaranteed disconnection of the pipe string from the liner, regardless of its length, in any interval of the well.

1 cl, 4 dwg