How important is sheet and plate steel flatness?
Fabricators are specifying temper-passed, leveled steel to remove coil memory By Greg Simpson March 14, 2002 This article examines flatness of steel, discussing the outcome of combining temper passing and leveling in the same line. It also provides the outcomes of experimentation on steel that has been leveled, temper passed, and both. Furthermore, it gives a few real world examples of who is using this process and what they are saying about it. Figure 1 Hot-rolled sheet coils generally reveal some or all symptoms of poor flatness. Steel has the tendency to cling to its original shape and molecular composition. Why? Because it was given a unique configuration when it was rolled, cooled, and coiled at the steel mill. In its natural state, steel is not at all flat. In fact, a hot-rolled sheet coil generally reveals some or all symptoms of poor flatness (see Figure 1). For example, 72-inch-wide material with a 100,000-PSI yield strength can have a crossbow of 2 to 12 in., wavy edges, and
