How important is sheet and plate steel flatness? -2

What Is Temper Passing?

Figure 2
Temper passing consists of compressing flat steel under very high pressure between two work rolls to flatten and elongate steel.

Temper passing is compressing flat steel under very high pressure between two work rolls to flatten and elongate it (see Figure 2). A cold reducing process, temper passing (also called temper rolling or temper pass) strives to decrease the material thickness between 1.5 and 2 percent (alternatively, elongating the coil 1.5 to 2 percent) without appreciable spreading, or widthwise elongation. At this percent reduction (or lengthwise elongation), temper passing increases the material surface’s yield strength and improves its finish.

Both integrated steel mills and coil processors have used temper-pass processing extensively. Initially, it was used in coil-to-coil processing as a way to improve surface finish, equalize surface stresses, and help reshape the incoming raw material.