Patent ID: 7909546

Claim:
A thread cutting insert, wherein on a common edge section between front and back faces of an insert main body, there is formed a pair of cutting edge sections that project from said edge section when seen from directions facing said front and back faces, and on at least two of four projecting faces of the pair of cutting edge sections there is formed a thread cutting edge with said projecting face serving as a rake face, with one of the at least two projecting faces with the thread cutting edge being provided adjacent to the front face of the insert body and another one of the at least two projecting faces with the thread cutting edge being provided adjacent to the back face of the insert body, wherein side ridgelines of two of said projecting faces are symmetric about a center line of said edge section that passes between these projecting faces when seen from the directions facing said front and back faces, and wherein the center line extends from a center of an attachment hole provided in the insert main body when seen from the directions facing said front and back faces.