Hot rolling mills are industrial facilities used for reducing the thickness of metal sheets or shaping metal sections by passing them through a series of heated rollers. There are several types of hot rolling mills, each designed for specific applications and metal processing requirements. Here are some common types of rolling mills.
This is the simplest and most basic type of hot rolling mill. It consists of two horizontally mounted rolls that rotate in opposite directions. The metal passes between the rolls, which exerts pressure to reduce the thickness and increase the length of the material.
In a three-high rolling mill, three rolls are instead of two. The top and bottom rolls are larger in diameter than the middle roll, which helps to reduce the thickness of the metal more effectively. The middle roll can be adjusted to achieve the desired thickness and shape.
A four-high rolling mill has four rolls—two large-diameter backup rolls and two smaller-diameter work rolls. The metal passes through the gap between the work rolls, which can be adjusted to control the thickness and shape of the material. Four-high rolling mills provide greater control and precision compared to two-high or three-high mills.
Bar mills are specialized rolling mills used for the production of bars, including round bars, square bars, and hexagonal bars. The mills can be designed to process various metals, such as steel, aluminum, and alloys. Bar mills typically include multiple stands of rolls and may incorporate additional processes such as cooling and finishing.
A section rolling mill is specifically designed for shaping metal sections, such as beams, channels, angles, and rails. The mill consists of a series of rolls that are shaped to produce the desired cross-sectional profile. Section rolling mills are commonly used in the construction, infrastructure, and manufacturing industries.
A continuous rolling mill, also known as a tandem mill or a continuous mill, consists of multiple stands of rolls arranged in a series. The metal is continuously fed into the mill and undergoes a series of reductions as it passes through each stand. Continuous rolling mills are highly efficient and are commonly used for high-volume production of long products such as bars, rods, and rails.
Cluster rolling mills have multiple sets of rolls arranged in clusters, with each cluster containing multiple rolls. The metal passes through these clusters to undergo multiple reductions in thickness. Cluster mills are used for rolling extremely thin sheets or foils.
In a tandem rolling mill, multiple stands of rolls are arranged in a series, and the metal passes through each stand successively. Each stand performs a specific reduction in thickness. Tandem mills are commonly used for high-volume production of sheets and plates.
Wire rod mills are designed for the production of wire rods, which are used in various applications such as construction, automotive, and electrical industries. The mill consists of multiple stands of rolls that gradually reduce the diameter of a metal billet or ingot, transforming it into a long, continuous wire rod.
A Steckel mill is a specialized type of rolling mill used for rolling thin slabs or plates. It combines the features of a four-high rolling mill and a continuous casting process. The mill allows for both hot and cold rolling of the material, enabling the production of a wide range of finished products.
In a planetary rolling mill, the work rolls are arranged around the center of the mill in a planetary motion. This design allows for high reduction ratios and improved control over the thickness distribution of the rolled material. Planetary rolling mills are often used for the production of seamless tubes and high-precision rolled products.
In a reversing rolling mill, the direction of rolling is reversed after each pass. The metal is rolled back and forth between the rolls, allowing for greater control over the thickness and shape of the material. Reversing mills are commonly used for the production of sheets, plates, and strips.
A universal rolling mill, also known as a universal mill, is a versatile type of rolling mill that can perform both hot and cold rolling operations. It is capable of rolling various types of metals, including steel, aluminum, copper, and alloys. Universal mills are used for a wide range of applications, from standard sheet and plate rolling to specialized processes such as shape rolling and ring rolling.
Plate rolling mills are designed for rolling large metal plates. They typically have three rolls—two side rolls and one central roll—and the plates are passed between these rolls to achieve the desired thickness and shape. Plate rolling mills are used in industries such as shipbuilding, construction, and heavy machinery manufacturing.
A hot strip mill is a specialized rolling mill used for the production of hot-rolled steel strips, which are commonly used in the automotive, construction, and appliance industries. Hot strip mills can process slabs of steel into long, flat strips in a continuous operation. They typically consist of multiple stands of rolls and incorporate various cooling systems to control the temperature and properties of the rolled strips.
These are some additional types of hot rolling mills that cater to specific applications and metal processing needs. Each type of mill offers unique capabilities and advantages, allowing for the efficient production of a wide range of metal products.