摘要 |
A threaded bolt having a shank of basic cylindrical form and with a root end and a head end is provided with a spiral-shaped external thread, which has at least one principal flight and in the vicinity of the root end has at least one lead-in flight, adjoined by the principal flight, where the lead-in flight has a lead-in surface which differs from the principal flight and is formed in order to come into crossing-free engagement with flights of a complementary internal thread of an element. The lead-in flight and the principal flight are interrupted by at least one groove, which extends in the longitudinal direction of the shank in order to form a free space for the accommodation of lacquer residues. The flights and the grooves are initially formed by rolling.
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