Pre-painted steel is a versatile product, which is widely used in construction, home appliances, furniture, and other industries. Also, there are many options in different base metals, paints, finishes, etc. on the market.
Information Required for Ordering Pre-painted Steel
According to the tables, when purchasing color coated steel, you need to confirm the following information:
1. What product do you need, steel sheet, coil, or steel strip;
2. Product specification and size;
3. Substrate type and zinc layer thickness;
4. Types and colors of top/back paint;
5. Surface finish requirements;
6. Painting structure and functions;
7. Weight (order quantity);
8. Use purposes;
9. Packing method;
10. Inner diameter size (coil);
11. Other requirements.
Prepainted galvanized steel coil
Suitable materials can not only meet the requirements of use but also minimize costs. When choosing color coated steel, it refers to choosing mechanical properties, substrate and coating thickness, top and back painting types, and performance. You need to take the following things into consideration, including use purpose, use environment, designed service life, durability, processing method, degree of deformation, etc. If you are still confused, welcome to contact Wanzhi Steel for help.
1. Mechanical Properties
Choosing the mechanical properties mainly depends on the factors such as application, processing method, and degree of deformation. For general uses with low strength requirements and deformation, DC51D and DC52D can be used as substrates. When there is a high requirement for formability, DC53D and DC54D are more suitable. For components with load-bearing requirements, structural steel will be better, such as S280GD, and S350GD.
2. Substrate Type & Coating Thickness
Choosing the substrate type and the coating thickness are mainly based on the application, use environment, and durability. For example, color-coated sheets for construction usually use hot-dip galvanized sheets, ZAM, and galvalume sheets as substrates because of their excellent corrosion resistance. In highly corrosive environments, a thick coating can increase durability and prolong its service life. In addition, when choosing a substrate, please pay attention to the corrosion resistance of cuts.
3. Top Paint
There are four commonly top paints, including PE, SMP, HDP, and PVDF, which are different in hardness, adhesion, durability, and other properties. PE is currently the most widely used coating, with average durability, good hardness and flexibility, and moderate price. The durability, gloss, and color retention of SMP are better, but its flexibility is slightly poor. HDP has better durability than PE, and it is more cost-effective. PVDF has excellent durability and good flexibility, but it is available in fewer colors and is more expensive. The top coat is mainly determined according to factors such as the use purpose, use environment, designed life, durability, the processing method, etc.
4. Primer & Back Paint
The common primers are epoxy, polyester, and polyurethane. Epoxy has good adhesion and high corrosion resistance, but it is not as flexible as other primers. Polyester has good adhesion and excellent flexibility, but its corrosion resistance is not as good as epoxy. Polyurethane is a primer with relatively good overall performance. The primer is usually selected according to the production process, use purpose, use environment, and the topcoat. While the back paint is usually selected according to the application and use environment. When the use environment is not corrosive, one layer of paint is OK. If it will be pasted with thermal insulation material, the back paint should be with good adhesion.
5. Paint Thickness
The paint thickness is closely related to the corrosion resistance of the color-coated sheet. Generally, the thicker the paint, the better the corrosion resistance. The thickness should be determined based on factors like the corrosiveness of the use environment, the expected life, and durability. While the gloss of the coating mainly depends on the application and preference. For example, low gloss and matt surfaces are better for construction uses, while gloss or high gloss color coated steel is preferred by home appliances.