DEVICE FOR CEMENTING TAIL IN WELL Russian patent published in 2007 - IPC E21B33/14 

FIELD: oil extractive industry.

SUBSTANCE: device includes tail with tubing column lowered into it, disconnector, provided with left thread for connection through the sleeve to upper end of tail, shoe with through channel and a sleeve. In accordance to invention device is provided with packing unit, consisting of body with cylindrical elastic sleeve pinned on it with circular external and internal grooves, abutting from below on rigidly mounted bushing and contacting moveable bushing from above, which is in its turn in contact with protective bushing. Spring stopper ring is mounted between ends of bushings. Protective bushing is equipped with shear screws, positioned in longitudinal grooves of body, connected by other ends of lesser diameter to controlling bushing, mounted inside the body, connected to it and made with cylindrical recess on end portion on internal side. Upper part of body is equipped with radial channels, covered on external side with elastic sleeve-valve. On ends the body is connected to sleeves with packing rings inside and plastic localizers outside. Upper sleeve is connected to tail, while lower one is connected to perforated portion of tail, and the latter is connected to shoe, between ends of which packing bushing is mounted. Tubing column with head on end in middle part is equipped with potting unit. The latter consists of branch pipe with cylindrical recess, mounted in which are spring stopping ring and a set of collars, loaded from above by potting body with radial channels, in original position closed by moving valve in form of barrel, connected to potting body and equipped with elastic ring. Upper part of tubing column is connected to sub, mounted inside the disconnector. Positioned between ends of disconnector and tail piece is supporting bushing, having two longitudinal thickened portions on internal side, positioned oppositely to each other, connected to sleeve of tail and interacting by upper ends of thickened portions with lower ends of connectors.

EFFECT: simplified construction, expanded functional capabilities of device.

4 cl, 2 dwg