| 摘要 |
A rotatable cutting tool (24) includes a cutting tool body (50) that has an axial forward end (52) and an axial rearward end (54). The cutting tool body (50) further has an axial length. There is a hard tip (58), which has a distal end, affixed to the cutting tool body at the axial forward end thereof. The cutting tool body (50) has a clearance portion (64) axial rearward of the distal end of the hard tip wherein the clearance portion has a transverse dimension. The clearance portion (64) includes an axial forward transverse dimension (E) and a minimum transverse dimension (F) that is axial rearward of the axial forward transverse dimension (E). The axial forward dimension (E) is greater than the minimum transverse dimension (F). The clearance portion (64) has an axial length equal to between about ten percent and about thirty-five percent of the axial length of the cutting tool body (50). |
