Galvanized sheet Galvanized steel is to prevent the steel surface from corrosion and prolong its life, the steel surface coated with a layer of metallic zinc, zinc-coated steel sheet which is referred to as galvanized sheet.
[Classification and Applications]
According to production and processing methods can be divided into the following categories:
a) hot-dip galvanized steel. The steel sheet was immersed in molten zinc bath, the adhesion to the surface layer of zinc sheet steel. At present, continuous galvanizing production process, namely the continuous roll of steel is immersed in the plating bath of molten zinc is made of galvanized steel;
b) alloyed galvanized steel. This plate is manufactured by hot dipping, but after the tank, immediately put it heated to about 500 ℃, it generates an alloy of zinc and iron coating. This galvanized sheet with good paint adhesion and weldability;
c) electric galvanized steel. This galvanized steel sheet manufactured with good workability by plating. But the coating is thin, the corrosion resistance is better hot dipping galvanized sheet;
d) single-sided and double-sided difference galvanized steel plating. Sided galvanized steel, that is only one side of galvanized products. In terms of welding, painting, anti-rust treatment, processing, it has a better than two-sided galvanized sheet flexibility. To overcome the disadvantages of single uncoated zinc, another one in another top coat with a thin layer of zinc galvanized sheet, namely the difference between double-sided galvanized sheet;
e) an alloy, composite galvanized steel. It is steel with zinc and other metals such as lead, zinc alloy and even made into a composite plating. This plate not only has excellent anti-corrosion properties, and good coating performance.
In addition to the above five kinds, there are colored galvanized steel sheet, galvanized steel sheet coated printing, polyvinyl chloride laminate galvanized steel sheet and the like. But still the most commonly used hot-dip galvanized sheet.
Galvanized steel can be divided into general use by end-use, roof, building outer plate, structural, tile ridge board, stretching and deep drawing, etc. galvanized steel.
The main production plant and imported production Country:
a) Domestic: Wuhan, Anshan Iron and Steel, Baosteel and Guangdong;
b) abroad: Japan, Germany, Russia and France.
Are set out in the relevant product standard recommended standard galvanized sheet thickness, length and width and tolerance. Can be found in the relevant product standard last section has to offer.
(1) Surface Condition: galvanized sheet coating process due to the different treatment, surface state is different, such as the common spangle, small spangle, smooth spangle, spangle-free surface phosphate processing and the like. German standard also provides surface level.
(2) galvanized sheet should have good appearance, without the use of harmful defects of the product, such as no plating, holes, cracks and dross, more than plating thickness, abrasions, chromic acid, dirt, rust and other white. Foreign standard provisions for specific cosmetic defects are not very clear. When ordering a number of specific deficiencies should be stated in the contract.
(1) the amount of the standard value galvanized: zinc amount is an effective way to a galvanized zinc coating thickness of commonly used representation. Galvanized amount in units of g / m2.
Japan, US and German standards provide for the amount of galvanized sheet metal galvanizing see "Table 1."
(2) Measurement method: sampling requirements and test methods, see the last one in the relevant standard.