Structural Profiles and Sections are obtained by hot rolling of bloom/billet and cold rolling of Strips cut from hot-rolled or cold-rolled steel coil. These include Angle, Channel, Girder, Joist, I Beam, H Beam etc.
Carbon steel, quality low-alloy, and alloyed steel grades are used to produce steel angles. Hot-rolled steel angles are manufactured from steel billets or blooms, while bent angles are made of steel coils cut into strips of the required width.
Depending on the application or specific operating conditions, angles can have a protective coating, such as zinc coating, impact-resistant paint (powder technology) or polymer-based film. They can also have fire protection. While additional options help to improve the functional properties of the finished goods, they also make the price higher.
The most common I-beams are hot-rolled steel I-beams manufactured by rail and structural, beam, or section rolling mills. The feedstocks for the beams are blooms and square billets made of carbon and low-alloy steel grades, while the required dimensions and tolerances are ensured with a special roll pass design.
Welding metal strips is another widely used technology to fabricate I-beams. In this case, steel sheets and coils of different grades and dimensions are used as source material.
Two key processes are used to manufacture steel channels: hot rolling at hot-rolling mills and forming at forming lines.
In the first instance, steel billets or blooms are reheated in a reheating furnace and fed to rolling stands, where they are formed to achieve the required cross-section by passing through numerous rotating roll grooves. Heavy, medium or light-section hot-rolling mills can be used to achieve the target size of channels.
Universal rolling mills with the horizontal and vertical arrangement of work rolls are used to produce parallel flange channels. Strips cut from hot-rolled or cold-rolled steel coils are used as feedstock in steel channel production. Formed channels are produced by sequential forming of the strip cross-section between the rolls of the forming mills.