After pickling stainless HRC, both sides of the strip section width 8-18mm long pass prevailing rough band called rollover. Since rollover after cold rolling can not eliminate a direct impact on the quality of cold-finished surface, so the general trimming delivery. In actual production, we should try to control the roll width.
Rollover formation mechanism and the reasons:
1. The Omo slab after grinding sharp edges and corners, but not side grinding, after heating and oxidation, side rough, the rough rolling mill stand, the four corners of the mill and will not repair the side surface of the metal plate to extend up to form a roll;
2. Roughing stand roll wear large, resulting in faster roll width widened;
3. The blank width fluctuation in the longitudinal direction so that the vertical roll trapezoidal side pressure control amount of instability, widening the width roll, cold rolled rollover cut without a net.
1. Rollover main slab side is not grinding and rough surface oxide upon heating, due to turn to the strip surface after rolling thin; if the original finish billet side, the corresponding heating, rough rolling process, oxidation also lighter, which can effectively reduce or do not see the rollover phenomenon.
2. When hot rough rolling edger appropriate amount of lateral pressure, can reduce the edging process slab flip side to the surface, decreased the width of the roll.
3. Slab longitudinal side recess casting can significantly reduce rollover coil width, and with different degrees concave side, reduce the width of two coil roll changes also will occur when the undercut amount is 3mm, steel coil the most obvious effect of reducing the width of the roll, while the degree of dispersion roll width is also reduced.