Introduction to rolling mill types for roll-long products

Jan 29, 2024

Long products refer to metal materials whose length is greater than the maximum width of their cross-section, such as steel bars, steel poles, rails, etc. These products are usually used in construction, machinery manufacturing, transportation, and other fields and have a wide range of uses. According to different classification standards, long products can be divided into different types. For example, according to the use, it can be divided into long products for construction and long products for machinery; according to the material, it can be divided into steel long products and aluminum long products. In addition, long products can also be classified according to their shapes and specifications, such as square steel, round steel, flat steel, etc. In summary, the extended product is a broad term that covers a variety of metal materials whose length is more significant than their maximum cross-sectional width.

The rolling mill is a mechanical device used to roll and shape metal materials. It is widely used in the processing of steel, non-ferrous metals, and other materials. For the rolling of long products, common rolling mill types include two-high mills, three-high mills, and four-high mills. This article will introduce these rolling mill types in detail.

1. Two-high rolling mill

The two-high mill is the most basic type of rolling mill and consists of two rollers arranged in parallel. When working, the metal material passes between two counter-rotating rollers and is compressed and stretched, thereby changing its shape and size. The two-high rolling mill has a simple structure and is easy to operate. It can be used to roll bars, wire rods, and profiles of various specifications. At the same time, due to its high efficiency and large output, it is widely used in the field of long product rolling. However, the two-high rolling mill has weak plate shape control capabilities, making it challenging to move thin-gauge plates.

Two and three-roll mill

The three-roll mill consists of three rollers arranged in parallel; the middle roller is the driving roller, and the upper and lower rollers on both sides are passive rollers. During operation, the metal material passes between three counter-rotating rollers and is compressed and stretched multiple times, thereby obtaining a more precise shape and size. Compared with two-high rolling mills, three-high rolling mills have more robust plate shape control capabilities and can be used to roll thin-gauge plates and strips. At the same time, due to the smaller diameter of the work rolls, the precision of the rolled long products is higher. However, the structure of the three-roll mill is relatively complex, and the operation and maintenance costs are high.

Three and four-high rolling mill

A four-high rolling mill usually consists of two work rolls and two support rolls. The work rolls exert pressure on the metal blank to undergo continuous rolling and extrusion, thereby changing its shape and size. The four-high rolling mill has many advantages, such as achieving higher rolling efficiency and better-forming accuracy, as well as increased stability and reliability, making it one of the indispensable pieces of equipment in many industrial production lines.

Four-high rolling mills are widely used in metallurgy, machinery manufacturing, construction, and automotive industries and can be used in a variety of metal processing processes, including rolled plates, rolled wire rods and rolled profiles. Four-high rolling mills are more adaptable and flexible, making them suitable for different materials and processes.

Pictured above are rolls manufactured by VK Transmission Equipment ( Subsidiary of FV Bearings)

In addition to the above common rolling mill types, there are also some special-purpose long-product rolling mills, such as stainless steel rolling mills, high-precision rolling mills, etc. These rolling mills usually adopt advanced processes and technologies, feature high precision, high efficiency, and high stability, and can meet the needs of specific fields.

In short, for the rolling of long products, different types of rolling mills have other characteristics and application ranges. In actual production, selection should be made based on factors such as product requirements, production scale, and cost control. At the same time, in order to improve the quality and performance of long products, the research and development and application of new processes and new technologies should be strengthened to promote the sustainable development of the long-product manufacturing industry.

In addition, with the continuous development of digital and intelligent technology, long product rolling will become more automated and wise in the future. For example, using technologies such as sensors, machine vision, and artificial intelligence to monitor, adjust, and control rolling mills can improve production efficiency and product quality. At the same time, by establishing a digital factory and an intelligent management system, the production process can be visualized and optimized to reduce costs further and improve competitiveness. Therefore, long-running product-rolling companies should strengthen their digital transformation and intelligent upgrades to adapt to changes in market demand and enhance their competitiveness.

In specific applications, the selection of long-product rolling mills should also consider factors such as reliability, stability, and durability. For some materials with high strength, high wear resistance, and high corrosion resistance, it is necessary to select rolling mill components and materials with corresponding properties to ensure long-term stable production. Besides, in order to reduce energy waste and environmental pollution, long-product moving should also actively promote energy-saving and emission-reduction technologies and green manufacturing concepts to promote the sustainable development of the industry.

To sum up, the types and applications of long product rolling mills are a complex and extensive field. In order to meet different needs and adapt to market changes, long-product rolling companies should continue to strengthen investment in technology research and development and innovation and improve product quality and service levels. At the same time, enhancing the application and promotion of digital and intelligent technologies and the implementation of green manufacturing are also essential directions for industry development. Only in this way can we achieve high-quality development of the long steel manufacturing industry and sustainable social and economic development.