| 摘要 |
<p>A MULTIPLE SPUR MULTIPLE SPIRAL GROOVE TWIST DRILL includes a flute, whose shank is clamped and secured to a tooling holder of a drilling machine and contains multiple spiral flute grooves; each flute groove is disposed on its peripheral a flute land, a cutting section is formed on a front tip of the flute land; a spur formed at where the cutting section and the flute land crossing each other; and a lead screw point with tapered thread being disposed at a center on the front of the flute to increase strength of the cutting section; and the flute groove in conjunction with the flute to fortify the overall structural strength to provide longer service life and cost benefits of the drill.</p> |
