METHOD FOR PIPE-DRIVING DRILLING IN WATER AREAS AND DRILLING TOOL FOR ABOVE METHOD REALIZATION Russian patent published in 2006 - IPC E21B25/02 

FIELD: well drilling, particularly to drill loose rock in water areas along with simultaneous core taking and well casing.

SUBSTANCE: method involves applying force to sealing member of removable core receiver to retain sealing member in its lower extreme position, wherein above force is equal or greater than friction force appeared during sealing member movement along removable core receiver. Drilling tool comprises drilling tool having cylindrical spiral spring 24 put on ejector pump body 13 between sliding sealing bush 23 and fungiform member 21 adapted to receive fishing member of removable core receiver. The spring has initial inter-coil pressure equal or greater than friction force between movable sealing bush 23 and body 13 of ejector pump.

EFFECT: increased core receiver fixation reliability inside casing pipe.

3 cl, 2 dwg