Cold rolled steel coil (CR coil) is essentially hot-rolled steel that is cooled at room temperature and then annealed and temper rolled. This process will produce steel coil with tighter dimensional tolerances and better surface finishes. Since the cold work hardening is caused by continuous cold deformation, it increases the strength and hardness of rolled hard coils and decreases the toughness index, they can only be used for simply deformed parts.

Cold Rolled Steel Coil Manufacturing Process

Raw Material (Hot rolled steel)- Pickling – Cold Rolling – Degreasing – Annealing – Rolling up – Packaging

1. Pickling. Hot-rolled coils pass through a pickling line to remove oxide scale on the surface by using hydrochloric acid solutions. Through the pickling process, there will be fewer surface flaws left.
2. Cold rolling. Pickled coils are rolled to a specified thickness in the cold-rolled mill.
3. Annealing. After removing the lubricant oil and contaminants by electrolytic cleaning, the coil will go through the continuous annealing process. It aims to make steel products with high tensile strength.
4. Rolling up into coils and then packaging for sale.

1. High strength: 20% stronger than hot rolled steel
2. High surface quality – smooth and easy to paint
3. Close tolerances
4. Good formability
Tensile strength is at least 270 N/mm2(MPa); while yield strength is ≤240 N/mm2(MPa).

Cold Rolled Steel Coil Uses
The cold-rolled steel coil is commonly used for applications that require close tolerances, high strength, and high surface finish quality. It is also the base metal of galvanized steel coil. Here are its applications:

1. Furniture
2. Automobile components
3. Home appliances
4. Electronics Hardware
5. Construction uses