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. When steel is above the recrystallization 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 due to the fact that it is often manufactured without any delays in the process, and therefore the reheating of the steel is not required (as it is with cold rolled). 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.
After the heating and rolling processes, the steel is cooled down (Allowed for room temperature), causing the material to shrink; therefore, it makes it difficult to keep the precision over the dimensions and shapes. That’s the reason why Hot Rolled Steel (HRS) is recommended to be used only under situations where sizes and tolerances are not essential.
- The Hot Rolled Steel is cheaper than Cold Drawn and Cold Rolled. As it is a steel that is produce without any delays in the process, and that does not require reheating process.
- It is more manageable. Perfect for construction, welding and railroad tracks.
- No precision in dimensions.
- Rough texture compared to the Cold Drawn and Cold Rolled.
What is hot rolled steel used for?
Hot rolled products like hot rolled steel bars are used in the welding and construction trades to make railroad tracks and I-beams, for example. Hot rolled steel is used in situations where precise shapes and tolerances are not required.