Hot Rolled Steel Square Bar
Compared to the sharp corners of cold rolled steel, HR steel square bar is characterized by its unique radius corners and softer, more pliable finish. Hot rolled square bar maintains excellent mechanical properties and is simple to fabricate through conventional methods including welding, hot forming and mild cold forming.
Hot Rolled Steel Square Bar ApplicationsHot rolled steel square bar is used in numerous types of industrial applications, including:
- Structural support
- General fabrication
Mechanical Properties of Hot Rolled Steel Square BarHot rolled square bar maintains many beneficial properties that separate it from other processes such as cold rolling. The properties that are exclusive to the hot rolled steel manufacturing process include the following:
- Tensile Strength: 67,000 psi
- Yield Strength: 45,000 psi
- Reduction of Area: 58
- Elongation in 2”: 36
- Brinell Hardness: 137
Manufacturing Process for Producing Hot Rolled Steel Square BarThe HR steel square bar manufacturing process involves rolling steel at a temperature above the steel’s recrystallization temperature, which is around 1700° F. Steel that is above the recrystallization temperature can be shaped and formed much more easily than colder steel, and the steel can start in much larger sizes.
Steel square bar stock is also less expensive to manufacture than cold rolled steel and is often produced without pauses or delays in the process, so the steel doesn’t need to be reheated. During the cooling process, hot rolled steel will shrink and the size and shape of the steel will be less predictable than cold rolled steel.
HR Steel Square Bar AdvantagesHot rolling usually uses large ingots and large reduction rolling, which not only improves production efficiency, but also creates conditions for increasing rolling speed and achieving continuous and automated rolling process. Some of the other benefits associated with hot rolled steel square bar include:
- Increased malleability
- Numerous applications
- Less expensive than cold rolling
- High rate of production
Cold vs Hot Rolled Square BarThe hot rolling process for steel square bar allows for the metal to be shaped and formed more easily and creates larger sizes. Hot rolling is generally less expensive than cold rolling since it can become a finished product without timing delays. Conversely, the cold rolling process increases the strength of the finished product by as much as 20 percent, while creating a gray finish that is smooth to the touch.
Both hot rolled steel and cold rolled steel start out in largely the same way and both can have the same grades and specifications. But cold rolled steel undergoes additional processing steps, resulting in improved properties that can be exploited for different applications. Each type of steel has its advantages and disadvantages and costs for the two types of steel can also vary widely.
ASTM 36 Square Bar Steel CharacteristicsHR steel square bar provides a wide variety of beneficial features, including:
- Slightly rounded edges and corners (due to shrinkage).
- Slight distortions, where cooling may leave slightly trapezoidal forms rather than perfectly squared angles.
- Scaled surfaces due to the extreme temperature cooling process.