Abstract: Method for manufacturing long bars, round, square or flat, employing multi-tandem type roller dies mechanism in which each roller gap is controlled by the roller gap adjusting mechanism, and apparatus preferably applicable that method. The apparatus is provided with a plurality sets of roller dies, controllers for outputting a respective target roller gap for each roller dies, roller adjusting mechanisms capable of shifting, in accordance with the commanding signals from servo devices based on the output target roller gap, each roller of each set of roller dies symmetrically about the axial line of the die hole formed by the roller dies, roller position sensors for measuring the respective roller gap in order to feed back the measured results to the servo devices, and a propelling mechanism for imparting a deformable blank propelling force.

Abstract: Method for manufacturing long bars, round, square or flat, employing multi-tandem type roller dies mechanism in which each roller gap is controlled by the roller gap adjusting mechanism, and apparatus preferably applicable that method. The apparatus is provided with a plurality sets of roller dies, controllers for outputting a respective target roller gap for each roller dies, roller adjusting mechanisms capable of shifting, in accordance with the commanding signals from servo devices based on the output target roller gap, each roller of each set of roller dies symmetrically about the axial line of the die hole formed by the roller dies, roller position sensors for measuring the respective roller gap in order to feed back the measured results to the servo devices, and a propelling mechanism for imparting a deformable blank propelling force.