| 摘要 |
FIELD: mechanical engineering and metal working. ^ SUBSTANCE: proposed drill comprises cutting part with end face surface, cylindrical body coming back from cutting part and stem. Aforesaid body features axis of rotation and at least one groove passing along its outer peripheral surface to end face surface. Note here that at least one groove has first helical part open to end face surface, and second helical part passing from first helical part rear end. Note also that second helical part is twisted in direction opposite to that of first helical part. ^ EFFECT: increased heat removal. ^ 22 cl, 3 dwg, 2 tbl, 2 ex |
