DEMOUNTABLE DRILLING BIT Russian patent published in 2015 - IPC E21B10/28 

FIELD: mining.

SUBSTANCE: demountable drilling bit comprises a body-sleeve, an adapter screwed into it in the direction of rotation during drilling, with a central air channel and a connection nipple for a drill rod, hoes having shanks on one side, and cone rollers on the other, the central air duct in the body-sleeve, a floating spacer cone contacting with the end of the adapter and the inner conical surface of the shanks, the outer surface of which is rested by means of an annular recess in the mating surfaces of the body-sleeve, which mating with the hoes also occurs on the surfaces capable to perceive the torque. The body-sleeve comprises the upper part connected to the annular recess and the lower part, forming an inner cavity with outlet air ducts, the surfaces capable to perceive the torque are formed on the lower part of the body-sleeve with the openings into the inner cavity, the hoes are installed into the openings, one side of each opening is the support collar for the hoe on the upper part of the body-sleeve, the lower part of the body-sleeve in the direction of drilling is provided with recesses outside to accommodate the cone rollers and its end part is provided with a device to secure a keeping forward drilling tool, or keeping forward rock destruction tools are mounted on it.

EFFECT: increased reliability of the device.

4 cl, 4 dwg