ROTARY DRILLING BIT Russian patent published in 2008 - IPC E21B10/08 

FIELD: building.

SUBSTANCE: invention concerns rotary drilling bits including a case and cone-shaped self-cleared cutters with peripherical gear and disk tips. The distinguishing feature of the bit is that the distance b₁ between vertexes of disks of a peripherical tip of one cutter is higher than length of a tooth b₂ of a gear peripherical tip of another cutter, these sizes correlating as follows: b₁/b₂=1.05-1.15. Note that platforms of blunting of cutting edges of gear tips are bigger than that of neighboring cutters disk tips.

EFFECT: increase in mechanical speed of drilling.

1 dwg