METHOD FOR SECONDARY DRILLING OF PRODUCTIVE FORMATION WITH CREATION OF SYSTEM FROM EXTENDED DRAIN CHANNELS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2012 - IPC E21B43/11 

FIELD: oil and gas industry.

SUBSTANCE: into the well at preset depth on tubing string there is lowered a device with side holes, in which movable block is tightly installed with possibility of axial movement and rotation, in the block there are installed mechanism for formation of holes in casing string and bent channel for movement in it providing outlet to annular space of high pressure connection hose with water jet nozzle attached to it providing creation in productive formation of the system composed of extended drain channels arranged on the same level in different directions against well axis due to working fluid supplied from the well head under pressure; at that movable block in the housing is installed with possibility of axial movement to stroke length comparable to axial distance between outlet of bent channel and hole for outlet of cutting tool providing fixation in housing in upper position with possibility of rotation providing alignment of holes for outlet of cutting tool with preset side hole of the housing with simultaneous isolation of bent channel of well annular space; also fixation in lower position with possibility of rotation is provided with alignment of bent channel outlet with side hole of the housing coaxial to preset hole in casing string with possibility of isolation of bent channel cavity from inner space of tubing string upon location of water jet nozzle in it; it is provided with mechanism for fixation of the housing in the well and with elements for control of position of cutting tool and water jet nozzle providing data transfer to the well head.

EFFECT: ensuring control of casing string opening and forming channels without extra lowering and lifting operations of tubing string and its movement along well shaft.

9 cl, 6 dwg