METHOD FOR CASING PIPE EXTENSION INTO WELL Russian patent published in 2005 - IPC

FIELD: oil production, particularly for extending casing pipes from below.

SUBSTANCE: method involves installing jointing connection pipe on lower end of casing pipe; grouting casing pipe; lowering additional profiled and cylindrical pipe column into well; securing upper end thereof in connection pipe; expanding profiled pipes by creating hydraulic pressure inside them along with following profiled pipes calibration and cylindrical pipes flaring. Before connection pipe installation on casing pipe connection pipe is bored from inner side thereof to obtain diameter, which provides additional column flushing with casing pipe. Then annular depression is formed. The annular depression is adapted to limit additional column lowering and cooperates with rests. Rests are secured to upper end of additional column. Cylindrical cup made of drillable material is formed in connection pipe cavity so that gap is formed between inner wall of connection pipe and cylindrical cup. The gap is filled with grease. After casing pipe grouting the cylindrical cup is drilled, well is bored and reamed and additional column is lowered in well.

EFFECT: increased reliability due to improved joining conditions and orientation of additional casing pipe inside the well.

7 dwg