Steel coil pretreatment: steel coil in the aluminum zinc plating before the need for a series of pretreatment process.

Aluminum-zinc coated steel coil is a commonly used building material, usually used for roofing, walling and other exterior decoration. It improves the corrosion resistance and durability of steel coils by applying an aluminum-zinc alloy coating to the surface of the coil. The following is the process flow of aluminum-zinc coated steel coil:

1. Selection of steel coil: First of all, you need to choose the right material for the steel coil. Commonly used materials include cold rolled steel coils, hot rolled steel coils and so on. According to different needs, choose the right thickness and specifications of the steel coil.

2. steel coil pretreatment: steel coil in the aluminum zinc plating before the need for a series of pretreatment process. The first is degreasing and descaling, removing grease and oxidized skin on the surface of the steel coil by acid washing or mechanical removal to ensure the adhesion of the plating layer. Then surface cleaning is carried out, using alkaline solution to remove residual impurities and dirt.

3. Preparation of zinc coating: Aluminum-zinc alloy coating is formed by electrochemical reaction in solution. First a solution containing appropriate amount of Al-Zn alloy needs to be prepared and poured into the galvanizing bath. The formulation and concentration of the solution will be adjusted according to different requirements.

4. Galvanizing process: The pre-treated steel coil is fed through a roller conveyor into the galvanizing bath, where the coil moves in a circular motion. Under the action of electric current, the aluminum-zinc alloy will form a uniform coating on the surface of the steel coil.

5. Coating: The galvanized steel coils need to be coated to improve the weather resistance and aesthetics of the surface. Common coating treatments include hot rolled coatings, powder coatings etc. These coatings can increase the corrosion resistance of steel coils and also provide a variety of colors to choose from.

6. Rolling and Cutting: After the coating treatment, the steel coils need to be rolled and cut to get the required size and shape. The coils can be cold rolled or hot rolled to change their shape and thickness.

7. Inspection and Packaging: The rolled and cut coils need to be inspected to ensure that the quality meets the standard requirements. The inspection includes the thickness, adhesion and corrosion resistance of the coating. Qualified steel coils will be packaged, usually in wooden crates or steel pallets for transportation and storage.

The process of aluminized zinc coils mainly includes steel coil selection, pretreatment, galvanization, coating treatment, rolling and cutting, inspection and packaging. Through these process steps, aluminized zinc coils with excellent quality and corrosion resistance can be prepared to meet the needs of different fields.