The stainless steels make up a family of materials with characteristics and properties considered peculiar. This is because the surface of stainless steels is protected by a layer of chromium oxide.
This is produced thanks to the reaction of chromium with the oxygen in the air, which means that in stainless steels it is not necessary to add protection for corrosion; in our previous articles you can get more information about the types of steels and their properties.
Stainless steels are used in a myriad of machinery, processes, products and construction, because they adapt perfectly to applications in the industry.
For each purpose of the steel, it is modified according to what is required, in this article we will talk about the finishes of rolling in stainless steel and their differences.
What are rolling finishes?
The rolling finishes, carried out by hot and cold rolling processes, are basically supplied in all flat stainless steel products. Rolling finishes meet requirements for application in the industry.
The most popular industry for which special requirements are met is construction, but they are also the basis for the processes used in modifying the surface according to the needs of construction and architecture.
To maximize the corrosion resistance of the supplied material, the surface finishes of rolling are pickled to remove the scale formed during the hot rolling processes and their subsequent annealing.
There are four important rolling finishes in the stainless steel industry.
Hot rolling
Classification 1D. This hot rolling is heat treated pickled: this means that it is hot rolled and annealed. Once the rolling scale is removed, this surface is classified as 1D finish.
This surface, typical of thicker sheets and plates, has low reflectivity and is mostly used where optical appearance is less relevant; they can be in support systems, in non-visible places and in structural applications.
Cold rolling
Classification 2D. It is a type of cold rolling heat treated pickled: this means that this surface is less rough than 1D, it is achieved by mixing with the cold rolled, annealed and pickled material.
The matte appearance of the surface is not very reflective, which makes it suitable for industrial and engineering applications, although in architecture and construction it is less used, it can also be an option.
Classification 2B. Another type of cold rolling, heat treated pickled and processed in Skin pass: Produced by the same process as the 2D surface, with a slight final rolling using very polished rollers that provides a smooth, reflective and grayish surface.
It is the most commonly used surface finish today and serves as the basis for most bright and polished finishes.
Classification 2R. The last type of cold rolling, annealed and bright: it is a very bright finish, which reflects images clearly, it is obtained by a heat treatment in atmospheric conditions without oxygen.
After a cold rolling using very polished rollers. This finish is very smooth and is less likely to harbor air contaminants, which makes its cleaning much easier.
The difference between cold and hot rolling
The hot rolling is ideal for robust products, such as train rails, elements for the construction of buildings, water heaters, racks and parts of heavy vehicles, anchors, etc.
In the case of cold rolling, it is usually used for elements with more demanding details and finishes. Also for those that will later be bent, stamped or set. Therefore, it is used for sheets and rods, tools and locksmithing, car parts, pressure vessels, metal furniture and for sanitary uses, machinery gears and bolts, appliances, etc.
At Ulbrinox we believe that achieving the desired finish is not complicated. It is simply a matter of understanding the desired result and following the established methodology and procedures.
Proper handling of tools and consumables is essential to ensure that the finish matches or is created in an appropriate and efficient way, managing to manufacture a piece with the exact finish.
For more information on how the surface finishes mentioned above can be achieved efficiently and successfully, or to discuss any technical issue you may have trying to get the finishes mentioned above contact us, at Ulbrinox we have specialists at your service.
