WELL CONSTRUCTION DEVICE Russian patent published in 2007 - IPC E21B7/00 E21B33/138 E21B10/18 

FIELD: deep well drilling for water, oil and gas production, particularly special methods or apparatus for drilling.

SUBSTANCE: well construction device comprises body with central channel, centrator having blades aligned with drill bit legs, two nozzles having the same diameters and arranged in centering blades in common plane transversal to central channel axis and hydraulically communicated with it. Nozzle axes cross each other at 90° angle. Jet rock bit is installed under the body. Annular grooves are made in centering body blades and extend along outer diameter thereof at level of nozzle locations with respect to longitudinal body axis. Point of nozzle axes intersection is in circle with diameter equal to jet rock bit spaced 2d_n distance therefrom. Distance between nozzle ends and nozzle axes intersection is equal to 4-5d_n, where d_n is nozzle orifice diameter.

EFFECT: increase well wall air-tightness and strength in permeable ground, increased reliability and provision of impervious screen forming inside matrix solid material.