ROTARY CUTTING TOOL, METHOD OF CUTTING BILLET FOR MANUFACTURING SEAMLESS TUBE AND METHOD OF MANUFACTURING SEAMLESS TUBE.

摘要

Disclosed are a rotary cutting tool which can suppress occurrence of a flaw on the outer surface of a seamless tube, a method of cutting a billet for manufacturing a seamless tube and a method of manufacturing a seamless tube. The rotary cutting tool (100) is a substantially circular rotary cutting tool along the outer circumference of which a plurality of blade parts (1) is provided. The end surface (11) of the blade part (1) on the downstream side in the rotational direction thereof is tilted at a relief angle θ of 1º-10º with regard to the thickness direction (Y) orthogonal to the rotational direction (X).