Steel strips are an important alloy for which the application areas are vast. In this article, we will look at the process for making cold-rolled strips or tempered steel strips. If you’re looking for a manufacturer of these strips, we recommend Steel Corp, a family-owned business that has been in the industry for decades.
Cold rolling of a steel strip is something used mostly in the deep drawing process, and the purpose for this process includes:
The process of cold rolling goes through these stages:
This is something that happens in a tandem rolling mill where there are 5-7 stands that have four-high configurations. This means two small work rolls and two large backup rolls.
This happens at a temperature that is 600-700ºC or 1100-1300ºF and in a controlled, reducing atmosphere where there is a mixture of nitrogen and hydrogen generally. This is to prevent oxidation of the steel surface. The annealing results in steel relief and recrystallisation of the steel grain structure. There are two alternatives to this process, that is batch annealing furnace and continuous annealing line.
In the latter, the steel strip, at a controlled speed, will pass the steel strip. In the former, the steel strip coils are placed one on top of another in a bell-type furnace. This allows achieving higher ductility and lower hardness as compared to alternative continuous annealing.
The last cold rolling operation is where the thickness reduction is conducted, so there is an impact of the required levels of surface finish, evenness, and hardness to the steel. For tempering, a four-high rolling mill is used.
To surmise the process, a cold-rolled steel strip is made from hot rolled steel coils, to put it simply. The cold rolling process is to change the mechanical properties of steel so that it can meet the bending and forming operations needed. This is also to get the surface finish that is required.
Further processing of a hot rolled strip is what gives cold-rolled strips. A hot-rolled strip is descaled through a mechanical process and with a combination of chemicals, after which the acids are removed.
The process of passing them through a cold-rolling mill is why they are called cold-rolled strips, as the steel is kept below the temperatures for recrystallisation. It is then rolled to the final thickness required.
Cold-rolling is done to achieve a change of the metal properties. The specifics of the properties are of different uses as sometimes you would need more ductility, and in other places, more hardness would be required.
As mentioned, we recommend Steel Corp, the best steel strips manufacturer. They sell tempered steel strips and other kinds of strips of the highest quality, so you will not be disappointed with the products and services being offered by them.