1. Pre-Treatment Process: Some rolling oil and other contaminants remain on the surface of cold rolled steel sheets following processing. These are removed by passing the electrically charged sheet through an alkaline solution which induces an electrochemical reaction.
2. Annealing: The material properties of the pre-treated steel sheet can be altered and improved through recrystallization during the annealing process.
3. Hot-Dip Galvanizing: After passing through the annealing furnace, steel sheets are dipped into a zinc pot where molten Zn is coated onto the surface. The desired coating weight is achieved by removing excess zinc before solidification with high-pressure air from an air knife.
4. Galvannealing: The surface of a steel sheet, after the air knife, can be coated with a zinc compound prior to reheating in an annealing process. Zn atoms diffuse into the Fe to create a Zn-Fe series alloy.
5. SPM & Chemical Treatment: In order to achieve a flat surface and an elegant finish, the steel sheet is processed with a skin pass mill. In order to prevent the white rust, which often forms on the surface of activated zinc, and to improve corrosion resistance, the surface is coated with a Cr-free resin.
6. lnspection & Coiling: In order to achieve a flat surface and an elegant finish, the steel sheet is processed with a skin pass mill. In order to prevent the white rust, which often forms on the surface of activated zinc, and to improve corrosion resistance, the surface is coated with a Cr-free resin.

1. lnput Process: Equipment at the entry point of the electrogalvanizing line consists of a pay-off reel, a shearing M/C, a welding M/C, a looper and a tension leveler. The pay-off reel transports stacked or cold rolled steel materials to the shearing machine which cuts and connects them in preparation for welding. Then comes the welding.
2. Pre-Treatment Process: An electrolytic cleaning line consists of an electrolysis tank, an acid bath and a rinse tank to remove contaminants and oxide films from the surface of the steel before electroplating.
3. Electrical Galvanizing: The CAROSEL method, among other electric galvanizing, involves the plating of one side at a time by means of a conductor roll. This process produces two-sided, single-sided, differential-sided plated sheets. There is also the horizontal type where two sides of a sheet are plated at the same time to produce a two-sided plated sheet.
4. Phosphate Thin-Film Coating: A phosphate thin-film is applied to the surface of the zinc layer through chemical or electrochemical reactions. The film is intended to provide temporary anti-corrosion protection and to generate a secure painting substrate.
5. Anti-Fingerprinting Process: An organic, inorganic or organic-inorganic hybrid film is applied to the surface of sheet steel in order to supplement its corrosion resistance and to enhance desirable properties such as resistance to fingerprint marks and workability.
6. Output Process: The exit point of the line includes an output looper, tension reel, and an automatic packaging line to protect the products after coil winding.