Hot Rolled And Cold Rolled Steel – What’s The Difference?
Steel is one component that is used in all kinds of construction projects. Steel is the preferred element of construction experts when it comes to manufacturing equipment, tools, or building concrete structures. Now, hot rolled and cold rolled steel, whether you’re someone looking to buy steel for business purposes, or simply, for building your home, you need to know its properties, the benefits, and so on.
There are so many types of steel available in the market, serving unique purposes. Choosing the wrong kind won’t just make you compromise with the quality of your structure, but also, would cause you to lose a significant amount of time and money.
Generally, steel is produced using hot and cold rolling processes. The steel produced by following these techniques is quite different from each other when it comes to properties such as malleability, strength, and so many others. It certainly doesn’t mean that steel produced using one technique is of a higher quality than the one produced using another method.
It’s just that these steel types are considered ideal for different purposes such as Steel rebar for a quality product. You could choose the right kind of steel on your own if you know quite a bit about it, or the right thing to do is to consult either a specialist, who’s helping you with a project or the manufacturers.
Benefits Of Hot Rolled
Both hot rolled and cold rolled steel can be produced in a manner that meets either high or low-quality standards. The steel is thus produced to meet the needs of the customers. The hot and cold rolled steel have different properties, and so, they are beneficial when used in specific situations. Generally, hot-rolled steel is used in automotive, agricultural equipment, railroad tracks, and so on.
On the other hand, cold-rolled steel is used in roofs and walls, home appliances, aerospace structures, and so on. Needless to say, they have intended benefits. A major benefit of hot-rolled steel is that since it is taken to a really high temperature, it becomes highly malleable at that point. It allows the manufacturers to mold it easily into desired shapes and sizes.
However, they do get compromised once the steel starts cooling down. The steel is considered ideal for use in areas where precise shape doesn’t matter as much. The hot-rolled steel can be produced in large quantities as well, which decreases the production time up to a great extent. After the steel is heated and shaped, it is allowed to cool down at room temperature.
Benefits Of Cold Rolled
This eliminates additional steps such as work hardening or quenching from the cooling process, making things easier and stress-free for the manufacturer. In the same way, there are quite a few benefits of cold-rolled steel as well. The steel produced through this process develops 20% more strength in comparison to the one produced using a hot rolled process.
Cold-rolled steel is manufactured following steps such as sizing, roughing, finishing, and so on, which causes it to have more uniform shapes. The use of this steel is considered ideal in situations where precise shape and size matter. The shapes are, however, limited to round, square, flat, and their variations.
During the cold rolling process, the steel is pressed using a powerful roller at room temperature. Because of this very feature, the final product doesn’t shrink down. On the other hand, this pressure technique is a time-consuming process, and so, only a limited amount of steel can be processed at any given time. In projects where aesthetics matter, cold-rolled steel fits the best.
Difference Between Hot Rolled And Cold Rolled Steel
The major difference between hot-rolled and cold-rolled steel is the way they are produced. As the name suggests, hot-rolled steel is rolled using heat. During this process, the steel is heated to cross its recrystallization temperature, which is above 1000 degrees Fahrenheit. Once the steel reaches that temperature, it is rolled into the desired shape and size, and then allowed to cool down.
It is during this process, that the steel gains most of its properties like strength, malleability, endurance, and many others. Steel produced like this is used for specific purposes. On the other hand, cold-rolled steel is produced using a high-pressure exerting roller. There is no application of heat in the cold rolling technique.
This very difference causes cold-rolled steel to gain properties that are quite different from hot-rolled steel. This makes cold-rolled steel ideal for situations that are different from the ones where hot-rolled steel is used. The steel produced by following the two techniques is different from each other when it comes to properties such as strength, ductility, finish, shape and size, and so on.
Steel Properties
Hot rolled steel cannot be molded as uniformly as cold-rolled steel. After the steel starts cooling down, it might take varied shapes which are generally not under the control of the manufacturers. The produced steel is then cut into required shapes using machines. Another property of hot-rolled steel is that it develops a scaly surface once it cools down.
It is then the job of the manufacturers to level the surface through the use of different techniques such as picking, grinding, or Sandblasting. Also, when the steel cools down, it shrinks down significantly. In the case of cold-rolled steel, since the steel is produced using the pressure of a roller, the manufacturer has quite a bit of control over the shape of the steel.
They can mold steel into the precise shapes or sizes that they desire. Another significant property of cold-rolled steel is that since there is no heating or cooling, there is no expansion or contraction in the size of the finished product. Unlike hot-rolled steel, cold-rolled steel has a more smooth and leveled finish. This saves the manufacturers an additional amount of time that they’d spend smoothing out the hot-rolled one.