BIT FOR DRILLING FLAT-BASE BORE Russian patent published in 2012 - IPC B23B51/02 

FIELD: process engineering.

SUBSTANCE: proposed bit has central axis and cutting end including first and second peak surfaces intersecting on central axis to make crosswise cutting edge. Note here that bisector intersects radially said central axis perpendicular to crosswise cutting edge to define first half of said bit on one side and second bit half on another side. Each said half comprises first curvilinear component of cutting edge formed by intersection of blade first surface and one peak surface. Note here that said first curvilinear component extends radially from said crosswise cutting edge. Second component of cutting edge extends radially outward from first component whereat, if seen from cutting edge, said cutting edge is aligned with said first curvilinear component to make smooth transition. Note also that first curvilinear component of each aforesaid half features positive axial front angle.

EFFECT: higher efficiency.

24 cl, 12 dwg