Benefits of Pickled and Oiled Hot Rolled Steel
Hot rolled steel and pickled and oiled (HRPO) hot rolled steel are both processed from the same initial material, but they undergo different treatments, resulting in distinct properties and characteristics. Here are the key differences between hot rolled steel and pickled and oiled hot rolled steel:
Surface Condition:
Hot Rolled Steel: Hot rolled steel has a scaly, rough surface texture due to the cooling process after rolling. It may have mill scale or iron oxide on its surface.
Pickled and Oiled Hot Rolled Steel: In the pickling and oiling process, hot rolled steel is first cleaned to remove the mill scale and any rust or oxidation. It is then coated with an oil or another protective layer to prevent further surface corrosion. As a result, HRPO steel has a smoother and cleaner surface finish compared to untreated hot rolled steel.
Corrosion Resistance:
Hot Rolled Steel: Hot rolled steel, with its rough surface, is more susceptible to corrosion and rust formation when exposed to moisture or environmental factors.
Pickled and Oiled Hot Rolled Steel: HRPO steel is protected against corrosion due to the removal of mill scale and the application of an oil or rust-inhibiting coating. This makes it more resistant to rust and oxidation.
Appearance:
Hot Rolled Steel: Hot rolled steel has a characteristic rough and scaly surface, which may not be suitable for applications where aesthetics are important.
Pickled and Oiled Hot Rolled Steel: HRPO steel has a smoother and more aesthetically pleasing surface finish, making it suitable for applications where appearance matters.
Weldability:
Hot Rolled Steel: The presence of mill scale on hot rolled steel can affect the quality of welds. It may need to be removed before welding.
Pickled and Oiled Hot Rolled Steel: HRPO steel's cleaner surface is more conducive to welding, as it does not require mill scale removal before welding.
Cost:
Hot Rolled Steel: Hot rolled steel is generally less expensive than pickled and oiled hot rolled steel due to the additional processing steps involved in the latter.
Pickled and oiled hot rolled steel is preferred in applications where a smoother surface finish, better corrosion resistance, and improved weldability are required. It is commonly used in manufacturing, construction, and applications where aesthetics or surface quality are important. On the other hand, standard hot rolled steel is used in applications where surface finish and corrosion resistance are not significant concerns, and cost is a primary consideration.