The quality regulations of high-quality grade galvanized coils include specifications, specifications, appearance, hot-dip galvanizing amount, organic chemical composition, plate shape, physical properties and packaging.
1. The packaging is divided into galvanized coils cut into lengths and lengths. It is usually packed in tinplate, lined with moisture-proof paper, and tied with an iron waist on the outside, which is firmly tied to prevent the inner window galvanized steel coils from rubbing against each other.
2. Specifications, models, specifications and related product implementation standards all indicate the specifications of galvanized coils that are strongly recommended for thin thickness, length, total width and tolerance. In addition, the total width and length of the board and the total width of the roll can also be specified according to customer regulations.
3. The appearance of the surface layer: due to the different treatment processes in the coating process of the galvanized coil, the surface layer is also different, such as general zinc flower, fine zinc flower, leveling zinc flower, zinc-free flower and its pickling phosphorus Surface layer etc. The galvanized steel coils and galvanized sheet coils cut into lengths and lengths must not have the disadvantages of hazardous applications, but the steel coils are allowed to have many abnormal parts such as welding positions.
4. Hot-dip galvanizing amount Hot-dip galvanizing amount index value: Hot-dip galvanizing amount is a widely used and reasonable way to express the thickness of the zinc layer of the galvanized steel coil. There are two types of double-sided hot-dip galvanizing (the same thickness hot-dip galvanizing) and double-sided hot-dip galvanizing (different thickness hot-dip galvanizing). The amount of hot-dip galvanizing is g/m2.
5. Physical properties (1) Compressive strength test: Generally speaking, only galvanized steel coils for construction, drawing and deep drawing have compressive strength characteristics. (2) Tensile test: It is a key new item to consider the performance of metal sheet. However, the regulations of various countries in the world are not consistent with the various galvanized steel coils. It is generally stipulated that after the galvanized steel coil is bent 180 degrees, there should be no zinc layer on both sides of the surface layer, and the board base must not be cracked or broken.
6. Organic chemical composition The regulations on the organic chemical composition of hot-dip galvanized steel sheets are different in the world. If the country of Japan does not stipulate, the United Kingdom does. Generally no finished product inspection.
7. Board shape considerations There are 2 index values for board shape, namely verticality and long knife bending. The specification of the verticality of the board and the larger control value of long knife bending have certain requirements.
