Hot‑Rolled Coil (HRC)

Hot‑Rolled Coil (HRC) is manufactured from continuous‑cast slab, continuously rolled at temperature above steel recrystallization temperature, laminar‑cooled and coiled into steel strip. Surface covered with mill‑scale (black oxide layer). Good ductility and weldability, cost‑effective. Can be cut‑to‑length, slit, pipe‑formed or stamped. It is fundamental raw material for welded pipe, cold‑rolled coil, steel structure and mechanical fabrication.

1. Main Types

1. By steel grade

‑Carbon structural steel: Q235B, SPHC, SS400. General‑purpose for steel structures, welded pipes and common components. ‑High‑strength low‑alloy steel: Q355B (16Mn). High yield strength for engineering machinery and heavy‑duty structures. ‑Hot‑rolled drawing grade: SPHC, SPHHD. Suitable for stamped parts. ‑Weathering steel: SPA‑H. For outdoor corrosion‑resistant components.

2. By surface condition

‑Black hot‑rolled coil (as‑rolled): Original mill‑scale, lowest cost, for further processing. ‑Pickled & Oiled coil (P&O): Mill‑scale removed by pickling, anti‑rust oil applied. Clean surface, reduces grinding work.

3. Size range

Thickness:1.5‑25 mm; width:600‑2000 mm; coil inner diameter:508 mm / 610 mm; coil weight:5‑30 tons. Available as cut‑to‑length sheets or slit narrow strips.

2. Production Process

Slab reheating → High‑pressure descaling → Rough rolling → Finish rolling → Laminar cooling → Coiling → Inspection.

3. Key Features

‑Hot forming provides excellent ductility, weldability and bending performance. Grain refinement eliminates casting defects, stable mechanical properties. ‑Lower cost than cold‑rolled coil; capable of heavy‑gauge production. Drawbacks: rough surface with mill‑scale; dimensional tolerance wider than cold‑rolled. ‑Pickled & oiled coil removes oxide layer for direct cutting & welding, higher price than black HRC. ‑Limitation: Not suitable for exposed decorative surfaces; painting or derusting is generally required.

4. Typical Applications

Steel‑structure buildings, supports, guardrails; raw material for ERW / spiral welded pipes; feedstock for cold rolling; machine bases, vehicle frames; containers, carriage parts; storage tanks, engineering machinery parts; cut‑to‑length plates, slit strips; base substrate for PPGI / PPGL color‑coated coils.

5. Standards

‑China: GB/T 3274‑2017 Hot‑rolled carbon & low‑alloy structural steel plates and strips; GB/T 709‑2019 Dimension & tolerance. ‑International: EN 10025, ASTM A36, JIS G 3101. ‑Russia / CIS: ГОСТ 14637‑89. EAC declaration required for EAEU export.

6. Selection Guidance

1. General structures & welded pipes: choose Q235B / SPHC. Heavy‑load & machinery: prefer Q355B.
2. Clean surface for direct fabrication: choose Pickled & Oiled (P&O). If further sand‑blasting is needed, black as‑rolled coil is more economical.
3. For Russia export: Q235B ≈ St3ps; Q355B ≈17Г1С.
4. Order specification: grade, thickness × width, coil weight range, surface condition, standard, MTC mill test certificate required or not.
5. Mill‑scale may fall off; keep dry during storage & transport to avoid rusting.

Details