| 摘要 |
A tapping tool comprises a threaded portion and an upper gripping shank, and presents an axial bore which has its base wall proximate to the end of the threaded portion and opens at the end of the shank, there being present in proximity to the base wall at least one duct which connects the bore to the outer surface of the threaded portion, and makes available on one side of the outer rim of the duct a sharp edge for removing the material, which then by passing through said duct collects inside the bore. |
