ROLLER BIT FOR HORIZONTAL DRILLING Russian patent published in 2015 - IPC E21B10/18 E21B10/20 

FIELD: mining.

SUBSTANCE: bit consists of sections, comprising roller bits installed with a possibility of rotating on cone pins of legs, and the legs. On the leg backs the vanes are provisioned which are designed as two or three screw-shaped ledges with trapezoidal profile with a lifting angle of screw-shaped line from 20 up to 25°. The bottom vanes on legs of the 1^st and 2^nd sections are designed at the same height from the bottom butt end of the bit so that the input butt ends of vanes are located below the top level of roller bits. The bottom vane of the 3^rd section is designed so that its input butt end overlaps target butt ends of the bottom vanes of the 1^st and 2^nd sections. The second from below vane of the 1^st section is designed so that its input butt end overlaps the target butt end of the bottom vane of 3^rd section. The second from below vane of the 2^nd section is designed so that its input butt end overlaps the output butt end of the second from below vane of the 1^st section, and the second from below fan of the 3^rd section is designed so that its input butt end overlaps the output butt end of the second from below vane of the 2^nd section etc.

EFFECT: possibility of mechanical removal of coarse slug and chippings of rock and metal, deposited on the bottom wall of well from the zone of bit operation, improvement of wear resistance of bit legs, forming of additional thrust load on a bit.

2 cl, 9 dwg, 2 tbl