Galvanized sheet is a steel sheet with a layer of zinc on its surface. Galvanization is a frequently used economic and effective rust prevention method, about half of the world's zinc production are used in this process. Galvanized steel is to prevent the surface of the steel plate from corrosion to extend its service life, the surface of the steel plate coated with a layer of zinc metal, this zinc-coated steel is called galvanized sheet. Surface state: Galvanized steel is treated differently due to the coating process, and the surface state is also different, such as ordinary zinc flower, fine zinc flower, flat zinc flower, no zinc flower, and phosphate treatment of the surface. The German standard also provides for surface grades. Galvanized sheet should have a good appearance, there shall be no defects harmful to the use of the product, such as no plating, holes, rupture, as well as slag, more than the thickness of the plating, abrasion, chromic acid stains, white rust and so on. Foreign standards on the specific appearance of defects are not very clear. When ordering some specific defects should be listed on the contract. Alloying galvanized steel. This type of steel sheet is also manufactured by hot-dipping, but immediately after leaving the tank, it is heated to about 500°C to produce an alloy film of zinc and iron. This type of galvanized steel sheet has good paint adhesion and weldability; single-sided and double-sided poorly galvanized steel sheets. Single sided galvanized steel sheet, i.e., a product that is galvanized on one side only.
In welding, painting, rust treatment, processing, etc., has a better adaptability than double-sided galvanized sheet. In order to overcome the shortcomings of single-sided uncoated zinc, there is a galvanized sheet coated with a thin layer of zinc on the other side of the galvanized sheet, i.e., double-sided differential galvanized sheet; there are also colored galvanized steel, stamped coated galvanized steel, PVC laminated galvanized steel, etc.. But the most commonly used is still hot dip galvanized sheet. The relevant product standards are listed in the recommended standard thickness, length and width of galvanized sheet and its allowable deviation. In general, the thicker the galvanized sheet the greater the permissible error, rather than a fixed 0.02-0.04 mm, the thickness deviation is also based on the yield, tensile coefficient and other different requirements, length and width deviation is generally in the 5mm, the thickness of the sheet is generally in the 0.4-3.2 between.
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