| 摘要 |
A thin sheet of metal is drawn in progressive steps to form a hollow body having a closed end tubular portion integrally connected to an outwardly projecting cup-shaped flange portion. A section of the tubular portion is crimped inwardly against a threaded mandrel to form helical threads and diametrically opposed and outwardly projecting double wall rib portions. The mandrel is unthreaded to form a sheet metal insert which is adapted to be supported within a mold cavity by a cylindrical support pin during injection of a plastics material into the cavity and around the insert. The threads and rib portions positively secure the sheet metal insert within the molded plastics article or part for receiving a threaded fastener. The insert may also be used in a metal part or casting or in a wood article, wherever threads are required or desirable.
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