Major diameter correcting re-roll thread rolling die

摘要

A thread profile is first rolled into a cylindrical work piece with a first set of thread dies, wherein the metal free-flows into the grooves of the first set of dies to form a rounded (or other shape) crest. Then the thread is re-rolled in a second set of dies having a reduced groove depth such that the rounded crest is re-formed and flattened. A thread profile may also be formed in a cylindrical work piece using a set of dies having surfaces containing two or more distinct groove shapes. Diagonally cut grooves encountered by the work piece would have a shape substantially identical to a “normal” die groove profile with a depth of D+H. Grooves in contact with the work piece as it exits the die would have a shape with a reduced groove depth of approximately “D.”