Which Is Better Cold Rolled Or Hot Rolled Steel?

Which is better cold rolled or hot rolled steel?

While hot rolled steel is heated then cooled, cold rolled steel is heated and cooled at the room temperature and then rolled after again. The steel is processed further in cold reduction mills, where the material is cooled (at the room temperature) followed by forming the material by either press-braking or cold roll forming to achieve the desired shape.

The term “rolled” is often used just to describe a range of finishing processes such as turning, grinding, and polishing, each of which modifies existing hot rolled stock into a more refined product. Technically, “cold rolled” applies only to sheets that undergo compression between rollers. But forms like bars or tubes are “drawn” not rolled. Hot rolled bars and tubes once cooled, are processed into what we call “cold finished” tubes and bars.

Advantages

– accurate shape (consistent and straight)
– a wider range of surface finishes
– a smooth and shinier surface
– bars are true and square and have well-defined edges and corners
– Tubes have better concentric uniformity and straightness.

Disadvantages
– more expensive
– fewer shapes available cold-rolled (sheets, box section shapes: CHS, SHS, RHS)
– additional treatments can create internal stress within the material; this can cause unpredictable warping if the steel is not stress relieved prior to cutting, grinding, or welding.