Galvanised Steel coils
Galvanised coils are thin steel sheets that have been dipped into a molten zinc bath so that a layer of zinc adheres to their surface.
Galvanised coils can be divided into hot rolled galvanised coils and cold rolled hot galvanised coils. They are mainly used in construction, household appliances, automobiles, containers, transportation and home industry. In particular, they are used in steel construction, automobile manufacturing and steel silo manufacturing.
They are characterised by strong corrosion resistance, good surface quality, ease of deep processing and economy.
What is a "zinc bloom"?
A zinc bloom is a surface appearance of a hot-dip galvanised sheet and coil, which occurs when the steel strip is coated with liquid zinc after passing through the zinc pan, and the zinc grain nucleation subsequently grows during the natural solidification of the zinc layer.
Zinc bloom generation is influenced by the composition of the coating and the cooling rate/method. When hot-dip galvanised sheet products first emerged, steel mills were not able to control the size of the bloom as they wished, and the surface of the produced hot-dip galvanised pure zinc coils had various sizes and shapes of zinc bloom, which at one time led to the belief that "only those with zinc bloom are hot-dip galvanised".
As steel manufacturing has improved, the process of hot-dip galvanising of thin sheets now allows a degree of control over the formation of zinc bloom, which is defined by the major international standards in force.
Classification of zinc flowers:
The European Standard (EN) is divided into two categories (EN 10346):
1. normal zinc bloom (N): no control of the solidification process of the zinc layer is required and various sizes of zinc bloom or no bloom are allowed;
2. Mini zinc bloom (M): requires control of the solidification process of the zinc layer, obtaining small zinc blooms (usually not visible to the naked eye).
The American Standard ASTM classifies three categories (ASTM A653):
1. Normal zinc bloom: does not require control of the solidification process of the zinc layer, allowing various sizes of zinc bloom to be generated during the natural solidification process;
2. Small zinc bloom: requires control of the solidification process of the zinc layer to obtain a relatively uniform and small size of zinc bloom, but still visible to the naked eye;
3. Zero zinc bloom: control means to obtain a fine zinc bloom that is not visible to the naked eye.
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Standard |
ASTM, AISI, DIN, GB, EN, JIS etc |
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Grade |
SGCC, DC51D, DX51D, DX52D, SGCD, SGHC, DX54D, S350GD, S450GD, S550GD |
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Thickness |
0.12mm-4.0mm or 0.8mm/1.0mm/1.2mm/1.5mm/2.0mm,etc |
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Width |
600mm, 762mm, 914mm, 1000mm, 1200mm, 1219mm, 1250mm, 1500mm |
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Zinc Coating |
Z30g-Z275g /m2, or as clients required |
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Spangle |
Zero spangle, regular spangle or normal spangle |
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Hardness |
Soft or hardness, as clients required. |
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Surface treatment |
Chromated and oiled, chromated and non-oiled, Anti-finger |
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Packing |
Waterproof paper+plastic film+iron packing+bundling or as per customers request. |
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Coil Weight |
3-8MT or as per requirement. |
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Application |
Corrugated steel sheet,Ceiling channel,industrial refrigeration,cold storage,door panel,sandwich panel,PU panel,writing board,PCM steel plate |
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Payment |
T/T, L/C at sigth. |
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Delivery Time |
In 15-30 after receipt advance or LC |
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Min order |
25 Mt (one 20ft FCL) |
