METHOD FOR REMOVING DRILLING BIT FROM ROD Russian patent published in 2013 - IPC E21B19/18 

FIELD: mining.

SUBSTANCE: method for removing a drilling bit from a rod involves installation of an intermediate element on the rod and transfer of force directed along the rod axis through it to the bit. The rod is fixed against axial movement; after that, forces in the form of torque are applied simultaneously to the bit and to the rod; at that, direction of the torque acting on the bit is opposite to the direction of action of the torque acting on the rod. Additional peculiar features of the above method are use of periodic reverse at transfer of torque to the bit and the rod and use for torque transfer of the assembly fixing the rod against axial movement, for example in case a machine cartridge is used for that purpose.

EFFECT: reduction of labour input at removal of a jammed drilling bit from the rod; improvement of efficiency of the bit removal method.

3 cl