DEVICE FOR WELL DRILLING Russian patent published in 2016 - IPC E21B7/00 E21B4/18 

FIELD: mining.

SUBSTANCE: invention can be used for well drilling. Device comprises lowered on sleeve in well casing with drill tool, installed with possibility of rotation of mechanical drive and axial displacement relative to housing. Housing is equipped with spacer mechanism. Rotation drive of drilling tool in housing there is a hydraulic motor with drive hollow shaft. Sleeve on which is suspended body is armoured and high pressure hoses are passed through it for supply of gaseous or liquid working medium, one of which is connected to hydraulic motor. Drill tool consists of upper and lower parts, each of which is mounted on hollow shaft to rotate in opposite directions from hydraulic motor driven hollow shaft. Hollow shafts of drilling tools are aligned to drive hollow shaft of hydraulic motor. Hollow shaft upper part of drilling tool encloses hollow shaft lower part of drilling tool, and hydraulic motor drive shaft is passed through hollow shaft lower part of drilling tool and is connected with hollow shaft upper part of drilling tool with possibility of axial movement relative to both hollow shafts of drilling tool. Spacer mechanism is made in form of installed outside housing with possibility of radial movement relative to housing by means of pneumatic or fluid cylinders of spacer dies connected to second high-pressure hose. Hollow shafts of drilling tool are installed in guide pipe thereof, connected with mechanical drive of axial movement of drilling tool and equipped with thrust flange. In lower part of housing and in lower part of drilling tool there are, communicated with armoured hose through cavity of housing, channels for supply of compressed air or drilling mud.

EFFECT: higher reliability with simultaneous improvement of efficiency.

1 cl, 1 dwg