Systemic research on cracking during bend and re bend test for big size bars produced with heat treatment has been done According to the research results,the definite and feasible technical measures and process modifications are put forwar

Work hardening modulus and reverse bend curvature in plate hot roller leveling;

Based on elastic-plastic theory and the characteristics of H-beam,the formulae of bending deflection and residual curvature of H-beam on rolling straightening have been deduced.

Research into inversed bending curve of the axis of the straightened pipe during straightening;