Hot rolling is a mill process which involves rolling the steel at a high temperature (typically at a temperature over 1700° F), which is above the steel’s recrystallization temperature. At this temperature it can be shaped and formed easily, and the steel can be made in much larger sizes. Hot rolled steel is typically cheaper than cold rolled steel. When the steel cools off it will shrink slightly thus giving less control on the size and shape of the finished product when compared to cold rolled. Billets and blooms are semi-finished steel products with square section produced via continuous casting technology. Billets and blooms are produced in a wide range of steel grades and serve as basis material for the warm rolling or are processed directly into forged pieces. Generally, blooms have a section measure of 160 mm or more, and billets have smaller measures.
