CROWN FOR WELL DRILLING IN EMISSION HAZARDOUS BEDS (VERSIONS) Russian patent published in 2013 - IPC E21B10/32 E21B10/60 

FIELD: mining.

SUBSTANCE: crown for well drilling includes hollow cavity with radial channels and slots on external surface and blades eccentrically mounted in them with contouring cutters and bosses located in radial channels of the casing. Between slots bottom and side surfaces of the blades directed to them there installed are the flexible elements connected to the casing or blades and protruding above them, note that according to the first version blade bosses are conical with the top located from the crown axis side, and casing radial channels - cylindrical. According to the second version the blade bosses and casing radial channels are conical, note that the top of conical boss of the blade is located from the side of crown longitudinal axis and the top of casing conical channel is located from the side opposite the crown longitudinal axis. According to the third version the blade bosses are cylindrical, and casing radial channels - conical with top located from the side of crown longitudinal axis.

EFFECT: increase of crown operation efficiency at drilling intermittent rocks, increase of drilling volumes of mineral deposits, more effective removal of gas from deposits, increase of works safety.

3 cl, 2 dwg