Method and Apparatus for Truing or Straightening Out of True Work Pieces

Author:  Garri Berstein
Source:  US Patent 5,001,917
Doc ID:  1991126
Year of Publication:  1991
Abstract:  
In a straightening or truing operation for straightening out of true work pieces the characteristic fatigue strength achieved in a previous strengthening operation of the work piece to be straightened, is maintained. This is achieved by a truing operation, wherein locally bounded compressive residual stresses are induced in a surface layer zone of the work piece by a hardening operation whereby the respective out of true deformation of the work piece is at least reduced. The truing operation may then be repeated until the out of true deformation is eliminated. The compressive residual forces are induced in a surface layer zone of the work piece by a locally bounded hardening operation or a strengthening rolling operation. By appropriately varying the extent of hardening or the rolling force respectively, the magnitude and angle of any out of true deformation may be affected so as to be even completely eliminated, for example. A machine for performing the method is also disclosed.