Hot rolled and cold rolled steel are not grades of the same product; they are different process routes with different thickness ranges, surfaces and forming behaviour.
| HR (hot rolled) | HR pickled & oiled | CR / CRCA | |
|---|---|---|---|
| Surface | Mill scale | Scale removed, oiled | Clean, bright or matt |
| Thickness range | Medium to heavy | Medium | Thin to medium |
| Dimensional tolerance | Wider | Wider | Tighter |
| Forming | Structural bending | Better than as-rolled | Pressing and deep drawing (grade-dependent) |
| Typical standard | IS 2062 / IS 1079 | IS 1079 / IS 2062 | IS 513 |
| Relative cost | Lowest | Higher | Highest |
Choose HR when
- The part is structural and will be blasted or painted after fabrication
- The thickness is beyond the practical CR range
- Tolerance and surface are not critical
Choose HR pickled & oiled when
- You need a scale-free surface for powder coating or pressing
- The thickness is at the heavier end of what CR offers, or CR is not justified
Choose CR (CRCA) when
- The part is pressed or drawn and needs a defined IS 513 grade
- Surface finish is visible or critical (panels, enclosures, furniture)
- Thickness tolerance matters for tooling