Q195 SPCC Cold Rolled Steel Coil SS400 Q235 Q345 Hot Rolled Carbon Steel Coil Low Carbon Steel Strips

Carbon Steel coil

The steel is rolled by hot pressing and cold pressing and the recrystallization temperature is the distinguishing point. The hot-rolled coil has poor toughness and surface smoothness, and the price is low, while the cold-rolled coil has good stretchability and toughness, but the price is more expensive.

Hot rolled steel has mill scaling on its surface, making it rough and uneven. This mill scaling can be removed with light sanding or deburring. 

Cold rolled steel is smoother to the touch, with no scaling that needs to be removed. This is thanks to working the material once it’s completely cooled.

The cooling process for hot rolled steel is imprecise as it happens slowly and at room temperature, allowing imperfections to form in the material. Hot rolled steel is most likely to experience distortion and varying thicknesses from sheet to sheet. 

Cold rolled steel experiences none of the same distortion because it is rolled while completely cool, flattening the material to a uniform thickness. This makes cold rolled steel better suited for uses where tight tolerances are needed.

Strength and hardness

With a lower yield strength and better workability, hot rolled steel is easily formed and extremely malleable. It is also harder than cold rolled steel because it is formed at high temperatures and cooled slowly.

Cold rolled steel has a higher tensile strength and higher yield strength, allowing it to undergo more stress and wear without warping. It is work hardened during the rolling process and is easily machined.

Application:

Hot rolled steel coil is mainly used in construction, light industry, automobile, agriculture, animal husbandry, fishery, commerce and other industries. The construction industry is mainly used to manufacture anti-corrosion roof panels and roof grilles of industrial and civil buildings; The light industry uses it to manufacture household appliance shells, civil chimneys, kitchen appliances, etc. the automobile industry is mainly used to manufacture corrosion-resistant parts of cars, etc; Agriculture, animal husbandry and fishery are mainly used as tools for grain storage and transportation, frozen processing of meat and aquatic products, etc; Commerce is mainly used as storage and transportation of materials,packaging tools, etc.

Production Process

1.The hot-rolled steel coil is made of continuous casting slab or pre-rolled slab as raw material, heated by a walking heating furnace, descaled by high-pressure water, and then entered into the rough rolling mill. Computer-controlled rolling, after final rolling, laminar cooling (computer-controlled cooling rate) and coiling by a coiler become straight rolls.

2.Hot rolled steel undergoes a rolling process that involves forming and rolling steel slabs into long, hot bands while heated at extremely high temperatures (typically over 1,700'F) above steels recrystallization temperatures.

3.The hot rolled steel is malleable at high temperatures, enabling it to be rolled into various shapes, forms, and sizes. After forming, the steel is cooled at room temperature, typically leaving a scaly surface finish that techniques like pickling can remove.

Packing and Delivery