What is Hot Rolled Steel?

From construction to manufacturing and beyond, hot rolled steel is utilized in countless industries for producing top-quality products that can withstand extreme climates and temperature shifts. Due to its perfect blend of strength, versatility, and economic efficiency, hot rolled steel is used to build skyscrapers and heavy equipment while driving manufacturing processes for the world’s most innovative and successful industries.

What is Hot Rolled Steel?

Hot rolled steel is produced by heating steel above its recrystallization temperature and then rolling it into the desired shape. This process imparts unique mechanical properties and a characteristic ribbed texture onto the material’s surface, which is later used as-is or further processed depending on the application.

Unlike cold rolled steel, which is processed at room temperature for tighter tolerances and a smoother finish, hot rolled steel offers excellent strength and ductility, making it perfect for applications that require heavy structural support and robust performance. Check out our other blog to learn about the key differences between hot and cold rolled steel.

The Hot Rolled Steel Manufacturing Process

Hot rolled steel is produced through a series of high-temperature processes that transform raw materials into durable, versatile products used to manufacture products for various industries and applications. The manufacturing process involves several critical stages, each designed to enhance the structural properties of the steel while maintaining cost efficiency for large-scale production. These include:

Raw Material Preparation

• Melting - Steel scrap or raw iron is melted in a furnace to produce molten steel. This step involves carefully managing temperature and chemical composition to achieve the desired alloy properties.

• Refining - The molten steel undergoes oxidation and desulfurization refining processes to reduce impurities and achieve the required chemical makeup.

Casting

The purified molten steel is then solidified using continuous casting techniques, where it is poured into a mold and cooled to form semi-finished slabs, billets, or blooms. This process sets the initial structure and homogeneity of the steel.

Heating

Once cast, the steel slabs are reheated in a furnace to a temperature above the steel's recrystallization point. This step makes the material malleable and ready for the subsequent rolling process.

Rolling

• Hot Rolling Process - The heated slabs are passed through a series of heavy rollers. As the steel moves through the rollers, it is reduced in thickness while being elongated and formed into the desired shape (such as plates, sheets, or structural shapes).

• Control & Precision - The rolling process is carefully controlled to achieve specific thicknesses, widths, and mechanical properties. The high temperature during rolling also helps to refine the grain structure, enhancing the steel's strength and ductility.

Cooling & Leveling

• Cooling - After rolling, the hot steel is cooled, often on a cooling bed or through controlled water spray systems, which helps manage the residual stresses within the material.

• Leveling - The cooled steel may be passed through levelers or straighteners to remove any warpages or imperfections, ensuring a flat and smooth surface.

Finishing Processes

• Descaling - Any scale or surface oxide formed during rolling is removed, often through pickling—a chemical process using acid solutions.

• Inspection & Testing - The hot rolled steel is then inspected for thickness, surface finish, and structural integrity. Mechanical testing verifies that the steel meets the required standards for strength and quality.

Hot Rolled Steel Mechanical Properties

Hot rolled steel is produced by rolling steel at elevated temperatures, resulting in unique structural and mechanical properties that make it ideal for numerous applications. Hot rolled steel properties include:

• Robust strength

• Enhanced pliability

• Withstands significant force and pressure

• More easily manipulated, welded, and machined than other steels

• Highly resilient

• Performs well in applications where toughness is required over extreme precision

Hot Rolled Steel Surface Characteristics

Unique surface characteristics, such as the presence of a scaled surface due to the cooling process and slight distortions and rounded edges resulting from shrinkage during cooling, allow for a distinct look and feel.

Hot Rolled Steel Advantages

The hot rolling process is integral to modern steel manufacturing, transforming raw materials into high-quality, cost-effective steel products. The benefits of hot rolled steel include:

• Exceptional strength and durability

• Enhanced formability and flexibility

• Impact and fatigue resistance

• Cost-effective manufacturing process

• Quick production turnarounds

Hot Rolled Steel Applications

Hot rolled steel’s versatility allows it to be customized for a wide range of applications, making it a critical component in many sectors. Additionally, its durability ensures lower maintenance costs and longer service life, translating to increased return on investment. Applications include:

• Construction - Utilized in the manufacturing of structural components like I-beams due to their toughness and ability to absorb impact and bear heavy loads.

• Material Handling – Used in the manufacturing of components for fork trucks, trams, cranes, and elevators, such as frames and rails.

• Agricultural Equipment - Production of machinery components such as tractors and combines.

• Automotive - Used in the production of underbody components, suspension, and chassis parts, leveraging its strength and formability.

• Pipe & Tube Manufacturing – Used in the creation of pipes and tubes for various applications.

IMS is Your Locally Trusted Provider of Hot Rolled Steel Products

With seven locations serving California, Arizona, Nevada, and Northern Mexico, IMS is your trusted source for various hot rolled steel products, including round bars, flat bars, square bars, sheets and plates, and tubes to meet your project needs.
 At IMS, we offer the following advantages:

• Same-day will-call pick-up

• Next-day local delivery

• Excellent high-volume discount pricing

• Advanced precision cutting services

• ISO 9001 certified

• Support of Just-In-Time manufacturing processes

• No minimum purchases

Purchase Hot Rolled Steel Products Today

Contact us for more information regarding our most popular hot rolled steel products and secondary service options. Our experts will assist you in finding the steel product that meets your project specifications.