DRILL BIT AND METHOD OF ITS ASSEMBLY Russian patent published in 2013 - IPC E21B10/22 

FIELD: mining.

SUBSTANCE: drill bit comprises legs, on inclined journals of which, made with circular grooves, there are mills installed, fixed by means of lock and stop elements, serially installed in radial channels of the mill and matched with circular grooves of journals. The radial channel in the mill is made as step-shaped, besides, the extent of the lower diameter is arranged at the outer side of the mill, at the same time the stop element is arranged in the form of a compression spring placed between the lock element and the support collar formed by a step of smaller diameter of the radial mill channel. In the method of assembly of the specified drill bit a lock element is first installed in the radial channel of the mill, then it is fixed with a stop element in the form of a compression spring, which is placed in the cavity between the lock element and the stop collar, formed by the step of the smaller diameter of the radial mill channel. The outer diameter of the stop element in compressed condition is selected as larger than the diameter of the smaller step of the radial mill channel.

EFFECT: increased efficiency of bit operation.

2 cl, 2 dwg