Cold Reduction

• Finishing mills will roll cold coils of pickled hot-rolled sheet to make the steel thinner, smoother, and stronger, through applying pressure, rather than heat.
• Stands of rolls in a cold-reduction mill are set very close together and press a sheet of steel from one-quarter inch thick into less than an eighth of an inch, while more than doubling its length.

Cold-Rolled Strip (Sheet)

• Sheet steel that has been pickled and run through a cold-reduction mill. Strip has a final product width of approximately 12 inches, while sheet may be more than 80 inches wide. Cold-rolled sheet is considerably thinner and stronger than hot-rolled sheet.

Cold Working (Rolling)

• Changes in the structure and shape of steel achieved through rolling, hammering, or stretching the steel at a low temperature (often room temperature).
• To create a permanent increase in the hardness and strength of the steel. 
• The application of forces to the steel causes changes in the composition that enhance certain properties. In order for these improvements to be sustained, the temperature must be below a certain range, because the structural changes are eliminated by higher temperatures.