| Abstract |
A CUTTING INSERT INCLUDES A TOP CHIP FACE, A BOTTOM SURFACE AND SIDE FACES EXTENDING THEREBETWEEN. AT EACH OF THE END FACES THE CUTTING INSERT HAS AXIALLY PROTRUDING PROTIONS, EACH OF WHICH HAVING A BEVEL. MAIN CUTTING EDGES ARE PROVIDED BY THE INTERESECTION BETWEEN THE TOP FACE AND RESPECTIVE SIDE SURFACES. ON EACH SIDE SURFACE THERE IS PROVIDED A CLEARANCE PORTION FORMED ON A PROTRUDING PORTION OF THER INSERT BODY WHICH VIA A STEP EXTENDS INTO A SECONDARY HELICALLY TWISTED CLEARANCE SURFACE, THE CHIP ANGLE OF WHICH INCREASES WITH INCREASING CUTING DEPTH. WITH THE CUTTING INSERT VIEWED IN PLAN, THE LEVEL IS ORIENTED PERPENDICULLARLY TO THE MAIN CUTTING EDGE. |