What is hot-rolled steel?
Abbreviation: HR
Related Terms
Cold-Rolled Steel(CR)
Cold-rolled steel is processed further after hot-rolling by passing through rollers at room temperature. It has tighter dimensional tolerances, a smoother surface finish, and higher strength than hot-rolled.
HRPO Steel(HRPO)
HRPO stands for Hot-Rolled Pickled and Oiled. It is hot-rolled steel that has been acid-cleaned (pickled) to remove mill scale and coated with oil to prevent rust. Preferred for stamping and laser cutting.
A36 Steel(A36)
A36 is the most common structural carbon steel grade in the US, defined by ASTM standard A36. It is weldable, machinable, and widely available as plate, sheet, and bar stock.
Mill Finish
Mill finish is the surface condition of metal as it comes directly from the rolling mill — no additional polishing or treatment. It often has a dull, slightly rough appearance with mill scale on hot-rolled steel.
Pickling and Oiling(P&O)
Pickling removes mill scale from hot-rolled steel using acid, and oiling applies a thin protective oil coat to prevent rust. The result is HRPO steel — a cleaner surface for stamping and laser cutting.