DRILL STRING DAMPER Russian patent published in 2012 - IPC E21B17/07 

FIELD: mining.

SUBSTANCE: invention relates to borehole drives of rotation, particularly, to hydromechanical drill string dampers. Damper has tubular case to accommodate thrust piston sleeve with top and bottom thrust faces and thrust bearing with thrust face arranged between case bottom face and spring mechanism bottom face. Thrust bearing thrust face and hollow adapter bottom thrust face a stay in contact with spring mechanism bottom face. Outer tubular elements accommodating thrust bush, spring mechanism and thrust piston sleeve are integrated into single module. Annular piston is arranged inside thrust piston sleeve to reciprocate therein. Rotary drive to transmit rotation between tubular case and hollow adapter is provided with impact ring arranged in hollow adapter to allow it to displace in lengthwise direction inside thrust bush.

EFFECT: linger life, higher reliability, lower costs of production servicing and repair.

4 cl, 6 dwg, 1 tbl