ROLLING DRILLING BIT (VERSIONS) Russian patent published in 2011 - IPC E21B10/22 

FIELD: mining.

SUBSTANCE: according to the first version, bit is assembled and includes housing with fixed rock-destructing elements and bit friction support, between which a damping device is arranged. Bearing assembly includes retaining bearing in the form of bearing spherical module containing inner spherical and outer races, as well as radial and axial sliding bearings arranged on journals of semi-axis and fixed on L-shaped bushing; at that, the latter is fixed in the bore of friction support formed on the leg side, and outer race of bearing spherical module is installed in bore of friction support formed on the bit housing side and one of faces of inner race interacts with axial sliding bearing located on L-bushing. According to the second version, retaining device is made in the form of a ball offcut on both sides, rigidly fixed on semi-axis with threaded connection and fixed against self-unscrewing by means of pins connecting along the axis the wall formed inside the ball with the face of semi-axis.

EFFECT: increasing service life of all bearings installed in friction support and increasing all the design performance criteria.

8 cl, 2 dwg