DEVICE TO CEMENT TAIL IN WELL Russian patent published in 2012 - IPC E21B17/06 E21B33/14 E21B43/10 

FIELD: mining.

SUBSTANCE: device designed to construct and repair wells, including directional wells, comprises a tail, a flow string (FS), a disconnector connecting an upper part of the tail with an outer funnel and a lower part of an FS with a seal assembly. In the funnel there are slots in the form of an inner circular recess. A fixator is arranged in the form of a split ring spring-loaded to the inside, and the seal assembly - in the form of a hollow body with an inner circular cavity and radial holes for stop balls, with movable outer and inner bushings. The inner bushing interacts from the inside with stop balls and is fixed relative to the body with a shear screw. In the lower part of the inner bushing there are two rows of radial channels, between which there is a seat for a ball. The inner bushing is arranged as capable of limited displacement downwards after ball discharge with release of stop balls and communication via the circular cavity of the body between upper and lower rows of channels. The outer bushing is arranged as capable of upward displacement relative to the hollow body with fixation in the upper position upon release of stop balls with further disengagement from the fixator as the seal assembly with the FS moves down relative to the tail.

EFFECT: invention makes it possible during subsequent rising of pipes to extract all parts of a device, apart from a tail fixed to a funnel and to carry out a technological process of tail disconnection and cementing in a single round trip.

2 dwg