Hot rolled steel tubes are manufactured by passing sheet metal through rollers to achieve specific physical dimensions. The finished product has a rough surface finish with radiused corners, and either a welded or seamless construction.
Manufacturing hot rolled square steel tubing involves rolling the steel at temperatures exceeding 1,000°F, which is above steel’s recrystallization temperature.
This makes the steel easier to shape and form into a tube.
A potential downside of the process is that there is less control over the dimensions of the finished product once it cools.
Because of these factors, hot rolled steel tube is best suited for applications that do not require precise shapes or tight tolerances.