Straightening unit for drawn round metal bars - has line of dies alternately contacting opposite sides of bar rotated by rotary end dies

摘要

Drawn round metal bars (1) are straightened by passing them through a line of straightening dies. The dies (6,7) are mounted in roller bearings so that they are free to rotate. The dies are so arranged that alternate dies are in contact with opposite sides of the bar. The bar is rotated about its longitudinal axis by rotating discs (2,3) at each end of the line of dies. The bar is subjected to forces which create a stress greater than the yield stress of the material during the straightening process. This method does not cause any change in nominal dimensions of the bar.