What is the Difference Between Hot Rolled (HR) & Cold Rolled (CR) Steel?

Hot rolling, the process used to make hot rolled steel, involves rolling steel at high temperatures (typically over 1700˚F). These high temperatures are above steel’s recrystallization temperature, allowing the steel to be easily shaped, formed, and made in larger sizes. As it cools, hot rolled steel tends to shrink non-uniformly, giving less control on the size and shape of the finished product when compared to cold rolled steel.

Characteristics of Hot Rolled Steel

Hot rolled steel tends to have a scaly finish which can be removed by pickling, grinding, or sand-blasting. This steel is essentially normalized, meaning free from internal stresses that can arise from quenching or work-hardening processes, because it is allowed to cool at room temperature. Other properties may include:

• Slightly rounded edges and corners for plate products (due to shrinkage and less precise finishing)
• Slight distortions
• More malleable and able to be turned into various shapes
• Increased ductility and toughness

Advantages of Hot Rolled Steel

Hot rolled steel tends to be cheaper than cold rolled steel because it is manufactured without any delays in the process and does not require reheating like cold rolled steel. It is also essentially normalized as it is allowed to cool at room temperature; this means it’s free from internal stresses that can arise from quenching or work-hardening processes.

Applications of Hot Rolled Steel

One of the many differences between hot and cold rolled steel is price. Hot rolled steel tends to be cheaper than cold rolled steel because it is manufactured without any delays in the process and does not require reheating like cold rolled steel. It can be used in applications where precise shapes and tolerances are not required, such as:

• Structural Components (Railroad Tracks, I-Beams, Sheet Metal)
• Agricultural Equipment
• Metal Buildings
• Stampings
• Automotive Frames

Aug. 28, 2021

A steel coil is a finished sheet or strip of steel that has been rolled or coiled so that the width of the sheet is greater than its thickness. Steel coils with certain coatings are weather resistant, moisture resistant and environmentally friendly. Depending on the desired result, steel coils are produced by different processes.

Hot-rolled steel coils are steel sheets that have been rolled at high temperatures, making the steel easier to handle. Due to the quick and easy process, hot rolled steel saves time and is less costly to manufacture.

Cold rolled steel coils have a better finish and are more durable than hot rolled steel. Cold rolling is a process where steel is rolled at room temperature, below its recrystallisation temperature. Although cold rolled steel coils are superior to other coils, they are more difficult to handle due to their higher carbon content.

Galvanised steel coils are made by the hot dipping process, which immerses the metal in zinc to obtain a nice smooth coating. This coating is highly resistant to rust and extends the life of the steel coil.

 Cold Rolled Steel Coils

Galvanised steel coils are produced by a hot dipping process, similar to galvanised steel, in which the metal is dipped into a liquid bath of zinc alloy and then heat treated in-line. Galvanised steel is usually thinner and easier to evaluate than other processes.

Printing steel coil is a product based on metal sheet, of which surface is firstly covered with coating and printing ink, and finally covered by the plastic film (PVC, PE). The coated layers of printing steel plate consist of chemical plating--- primer layer, pattern printed layer, and filming cover. The top and back coatings shall be generally weather resistant coatings, and coatings with special functions, such as stain resistant, self-cleaning, high heat resistance, antistatic, sterilization, anti-fingerprint and etc.

Steel coil industry and applications

Steel coil is a versatile product that can be used in the following industries.

Automotive

Household appliances

Agriculture

Construction

and much more!

Talk to an expert today to get a bespoke solution for your application.

 Hot-Dipped Galvanized Steel Coil

Storage of Steel coil

When working with steel products such as coils and angles, it is important to know how to store unused products safely in your warehouse. By storing it carefully, you can avoid the risk of these items tipping over and hitting people.

When storing steel coils, you can choose to place them on the floor or on support racks. Once you have chosen, you will need to learn about the two most suitable storage systems.

Vertical

With this system you can stack coils together, place separators in between and stop when they reach a total height of 3.3 metres. Those who choose to place their materials vertically need to remember to firstly stack them from the largest to the smallest diameter. Secondly, when they are stacked together, they should all form a centre line.

Single height

You have chosen to place the coils individually and side by side. This is the lowest risk form of storage. All you need is to place a restraining device on each item to prevent it from rolling.

 Printing Steel Coil

Horizontal

Some construction companies use horizontal stacking, but it is not usually recommended. It is unwise to use this system as the horizontal position makes it easier for coils to roll and fall than the other two previous methods. If the surface of an item is not painted properly, there is an increased risk of the item leaving the shelf. Secondly, workers such as yourself use incorrect bearing holders to wrap these materials together or place the correct materials inaccurately.

Ask the experts

As a leading steel coils supplier in China, Ever-shine Building Materials has always provided our customers with the highest quality products. We pride ourselves on investing time and effort in helping you find the right product for every project you handle.

Ever-shine Building Materials offers a complete range of customisable steel coil options in a variety of sizes, grades, finishes and forms. As one of the highest customer satisfaction metal supply companies, our team of experienced engineers ensure that each coil is tested and outperforms other competitors' products.

Our company passed the ISO 9001 international quality certification system, we can customize products to meet customer's demands. Our Q.C personnel along with R&D team are continuously working to ensure strict adherence to international standards. Each lot of goods are strictly inspected before delivering to our customers and we supply customers with inspection certificate.

Let us help you find the best steel coils for your project. When you contact us, please provide your detailed requirements. That will help us give you a valid quotation.