| 摘要 |
Improved thread rolling dies are disclosed forming fasteners with a cylindrical threaded portion and a threaded pointed portion. Such dies provide a polished rise angle surface for forming and threading the pointed portion of the fastener so as to promote slippage between such surface and the pointed portion of the fastener. The polished rise angle surface improves point formation, provides better filled threads, reduces burning of the fastener and increases die life. The dies also provide a match point spaced from the end of the short die so as to reduce the likelihood of improper timing when the dies are set up in the thread rolling machine. Further the dies provide an angulated top of the rise surface to break off any whiskers or tails which might otherwise project beyond the end of the point of the fastener being formed.
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