The G2L and H2L series machines have been built with basic leveler cassette into frame that is nearly the same as a precision straightener. The L series straighteners have all the same features as our standard precision straighteners and incorporates manual roll bending into our precision straightener family.
Standard straighteners can remove the basic shape defects in coil strip such as coil set and crossbow, they also can reduce the amount of edge wave and center buckle to some extent. But for the more severe coil defects and critical flatness applications, roll bending machines will remove much more edge wave and center buckle than a standard straightener.
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How bending the work rolls can correct strip shape
By bending the work rolls you can selectively work some zones of the strip (from edge to edge) more than other zones causing elongation. The basic principle is to elongate the short zones to match the length of the long zones.
Elongation occurs due to working the material and differential path length thru the leveler.
Typical roll bending to eliminate center buckle. The short edges are worked harder than the long center.
Typical roll bending to eliminate edge wave. The short center is worked harder than the long edges.