The Hot Strip Mill Looper System

In the modern hot strip mill, the loopers establish a low and relatively constant level of tension between stands. This aids in minimizing width deviation, and provides an isolated environment for the operation of automatic gage control equipment at each stand. The looper also serves to keep all stands of a mill in synchronism during speedup and slowdown when metal is in the mill. The flexibility of control which is inherent in adjustable-voltage looper systems permits the incorporation of a number of features which contribute to the effectiveness of the drive. Static and dynamic characteristics of electric hot strip mill looper systems are reviewed.