Stretch-bending straightener

Abstract

The invention relates to a method and stretch-bending straightener for straightening metal strips () by stretch-bending, comprising a plurality of straightening rolls () which are arranged behind one another in the strip flow direction (D) and spaced from one another in the strip flow direction (D), wherein the strip () subject to tensile stress below the limit of elasticity is alternately bent around the straightening rolls (), undergoing plastic elongation, wherein a deflecting roll () is arranged upstream of one or more straightening rolls (), respectively, wherein said straightening rolls can be adjusted relative to the strip () and wherein said deflecting roll has a larger diameter than the respective downstream straightening roll. Said method and said system are characterized in that, in order to vary the immersion depth, the straightening rolls () can be adjusted relative to the associated deflecting roll () such that the free strip length (F) between the nm-off point () of the strip () from the deflecting roll to the run-on point () of the strip () onto the associated straightening roll does not exceed a predefined maximum value, above which longitudinal undulations of the strip form. The system is preferably designed such that, as the immersion depth and/or the angle of contact are varied, the free strip length never exceeds the maximum value over the entire adjusting range.