METHOD FOR REANIMATION OF BROKEN DOWN WELLS WITH REPLACEMENT OF NON-HERMETIC UPPER PORTION OF CASING COLUMN AND PIPE CONNECTING DEVICE FOR REALIZATION OF METHOD Russian patent published in 2005 - IPC

FIELD: oil and gas industry.

SUBSTANCE: method includes determining length of non-hermetic upper portion of casing column, detaching of defect portion and removing of it from the well. At surface a column for mounting as a replacement of defect one is prepared, on its lower end through threaded sub a pipe connecting device is fixed. On both ends of sub inner threads are made, and inside its body longitudinal channel of two diameters and two shelves are made. Diameter of pass channel of sub is equal to inner diameter of connected pipes, and diameter of second channel is made for outer diameter of pipe, left in the well. Body of pipes connecting device at upper end has outer thread, by which it is screwed into lower threaded end of sub. In the body an inner longitudinal channel for passing of upper end of pipe left in the well is made. In inner longitudinal channel of body from upper end a recess in form of ring recess is made, wherein a compactor is loaded, and on upper side a bushing is mounted. Below ring recess around body circle no less than three slanted cylindrical channels are made, slanted inside towards its longitudinal axis, with output of their lower open ends into inner longitudinal channel of body. Into said channels balls, spring-loaded from above, are loaded. From lower end in the body a guiding end piece is fixed, inner surface of which is made in form of cone, widening downwards. Prepared column is lowered into well as replacement of defect one. By cone of end piece column during lowering is centered in well shaft and by inner longitudinal channel of body of pipes connecting device is placed on upper end of casing column left in well until its end is stopped against inner shelf of sub. At the same time balls in slanted cylindrical channels hold the pipe and rigidly connect body with pipe, preventing their axial displacement and rotation relatively to each other. After that finishing rotation of replaced upper portion of casing column along thread of lower end of sub is performed to provide reliable pressurization of connected pipes ends by a compactor. Behind-column space of replaced upper portion of casing column can be isolated be cementing compounds. Well is equipped for extraction of bed fluid and is launched into operation.

EFFECT: higher safety, higher reliability, simplified operations, lower laboriousness.

2 cl, 1 dwg