FACILITY FOR CEMENTING TAIL PIECE IN WELL Russian patent published in 2009 - IPC E21B17/06 E21B43/10 

FIELD: oil and gas industry, mechanical engineering.

SUBSTANCE: suggested invention refers to oil producing industry, particularly to construction and repair of controlled directional wells. The facility consists of a tail piece composed of pipes, and of an upper coupling with a left hand thread. The tail piece is connected to a disconnector in form of a mandrel sub, which is connected to lifting pipes in its upper part, and in its lower part it is connected via the upper coupling to the flow string, consisting of two sections. From below the tail piece is connected to a packer unit assembled of a case with a circular narrowing, of a rigidly installed on the case foot bushing, above which a cylinder elastic collar with circular internal grooves is assembled on the case; this collar rests at the opposite from the foot bushing side on a movable bushing equipped with internal circular grooving, wherein a spring stop ring with cuts is inserted; the cuts interact with counter directed notches of the case. The movable bushing is also equipped with shear bolts installed in lengthwise slots of the case and connected from inside with a guiding bushing arranged inside the case and connected with it by means of shear elements. The facility is easily assembled at the head of the well by means of alternate assembly of the column of the tail piece and units connected to it first, and then by lowering the tail piece of the column and units connected to it into the flow string.

EFFECT: increased reliability of fixture operation, elimination of round-trip operations causing fitting of before pumping cement groute.

5 cl, 3 dwg