Steel Plate

1. Classification by thickness
(1) Thin plate: Thickness <4 mm
(2) Medium plate: 4 mm~20 mm
(3) Thick plate: 20 mm~60 mm
(4) Extra thick plate: 60 mm~115 mm

2. Classification by production method
(1) Hot-rolled steel plate: The surface of the hot-rolled steel plate has oxide scale and the thickness of the plate has a difference. The hot-rolled steel plate has low hardness, is easy to process, and has good ductility.

(2) Cold-rolled steel plate: The surface of the cold-rolled steel plate has no oxide scale and is of good quality. The cold-rolled plate has high hardness and is relatively difficult to process, but it is not easy to deform and has high strength.

3. Classification by surface characteristics
(1) Galvanized sheet (hot-dip galvanized sheet, electro-galvanized sheet): In order to prevent the steel sheet from corrosion and prolong its service life, a layer of metal zinc is applied to the steel sheet surface.

Hot-dip galvanizing: The thin steel sheet is immersed in a molten zinc bath to make a thin layer of zinc adhere to its surface. At present, the continuous galvanizing process is mainly used for production, that is, the rolled steel sheet is continuously immersed in a molten zinc plating bath to make a galvanized steel sheet

Electro-galvanized: This galvanized steel sheet manufactured by electroplating has good processability. However, the coating is thin and the corrosion resistance is not as good as that of hot-dip galvanized sheet.

(2) Tinplate: A cold-rolled thin steel sheet with an extremely thin layer of metal tin on both sides. It combines the hardness and strength of steel with the easy welding, corrosion resistance and bright appearance of tin.

(3) Composite steel plate: It can be divided into two categories according to its combination type, namely metal composite steel plate and non-metal composite steel plate.
(4) Color coated steel plate: Commonly known as color steel plate, it is made of high-quality cold-rolled steel plate, hot-dip galvanized steel plate or aluminum-zinc-coated steel plate as the substrate, after surface degreasing, phosphating, chromate treatment, coating with organic coating and baking.

4. Classification by use
(1) Bridge steel plate: Thick steel plate specially used for manufacturing bridge structural parts, using special steel grades of carbon steel and low alloy steel for bridge construction.

(2) Boiler steel plate: Widely used in petroleum, chemical, power station, boiler and other industries, used to make reactors, heat exchangers, separators, spherical tanks, oil and gas tanks, liquefied gas tanks, nuclear reactor pressure vessels, boiler drums, liquefied petroleum gas cylinders, hydropower station high-pressure water pipes, water turbine vortex shells and other equipment and components.

(3) Shipbuilding steel plate: Thin and thick steel plates made of special shipbuilding structural steel used to manufacture the hull structure of ocean-going, coastal and inland ships. Shipbuilding structural steel includes carbon steel and low alloy steel, and the steel number is marked with C (ship) at the end.

(4) Armor steel plate: In military, it is usually composed of solid metal or non-metallic materials on military equipment and facilities, which can defend against certain energy physical attacks (including kinetic energy, thermal energy, electromagnetic radiation, etc.) and reduce damage to the protected target.

(5) Automobile steel plate: Refers to the structure used in automobile manufacturing. It is mainly composed of plate and special steel. It has the characteristics of high strength, thin gauge and corrosion resistance. It has a high level of production technology and is a high value-added product. The thickness of automobile steel plate is generally 0.8-1.2mm. Due to different external skin structures, the thickness is also different, and the maximum thickness reaches 3MM.

(6) Structural steel plate: Refers to steel that meets specific strength and formability grades. Formability is expressed by the elongation after interruption of the tensile test. Structural steel is generally used for bearing and other purposes, in which the strength of steel is a heavy design standard. Structural steel is a type of special steel.