| 摘要 |
An improved thread-forming screw has a circular threaded main body portion and a tapered lobular pilot or thread-forming section comprising a plurality of transverse elongated projections or lobes on a circular conical core, each lobe having a sharp ridge running the full length thereof. The sharp edges on the lobes minimize the torque required to form threads in a workpiece, while the circular main body portion maximizes the holding power of the screw in the workpiece.
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