Patent ID: 9604270
Date: 2017-03-28
CPC Classifications: B21B,B21D

Claim:
1. A method of stretch-leveling metal strip, the method comprising the steps of: gripping the strip with an upstream set of infeed tension rollers and, downstream therefrom in a strip-travel direction, with a downstream set of outfeed tension rollers; rotating the upstream and downstream tension rollers so as to tension the strip between the upstream and downstream sets and move the strip downstream in the strip-travel direction; passing the strip between the sets around individually supported relatively rotatable stretch rollers spaced in the travel direction to plastically stretch the strip; engaging the strip downstream of the stretch rollers and upstream of the downstream set with a plurality of straightening rollers spaced in the travel direction to reduce curvature and residual tension of the strip and also to plastically stretch the strip; and relatively orienting the straightening rollers and a furthest upstream roller of the stretch rollers such that the strip engages the straightening rollers in a region extending angularly over a wrap angle that decreases downstream from roller to roller and such that at the stretch rollers the wrap angle of the strip decreases in the travel direction by a greater amount than in the plurality of straightening rollers.