| 摘要 |
The invention concerns a drill comprising a generally cylindrical body (2), tipped with a head (3) and provided, over at least part of its length, generally spiral evaporating grooves (5). The groove(s) (5) is/are delimited, over at least part of its/their length, by a succession of facets (7), attached to one another, and linked to one another by sharp edges or by radius blends (8).
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