BIDIRECTIONAL DIES Russian patent published in 2019 - IPC E21B23/06 E21B33/129 

FIELD: mining.

SUBSTANCE: downhole tool that is retained in the wellbore by means of a unidirectional die and bidirectional die. Bidirectional die has a die frame and at least two blocks of dies. Die frame comprises a central ring and a plurality of planks extending longitudinally up and down the wellbore from the central ring and located at a distance from each other along the radius around the central ring, forming at least two pairs of slots. Each pair of slots has a first slot extending longitudinally up the wellbore from the central ring, and a second slot extending longitudinally down the wellbore from the central ring. Blocks of dies have the first gripping unit, the second gripping unit and groove between the first gripping unit and the second gripping unit. First gripping unit and second gripping unit have outer surface configured to grip casing string. First gripping unit is configured to slide into first slot, and second gripping unit is configured to slide into second slot, as a result of which the block of dies has a set position, in which the groove receives a part of the central ring, and the first gripping unit and the second gripping unit extend radially outward from the die frame in order to be able to engage with the casing, and the block of dies has an unstated position, in which the block of dies is pushed radially inside relative to the set position.

EFFECT: improved efficiency of a downhole tool.

18 cl, 26 dwg