0.12mm-6.0mm Thickness galvanized steel coil GI Coil Hot Dip Galvanized Coil

Product Description

Galvanized coil, a thin steel sheet that is dipped in a bath of molten zinc to adhere a layer of zinc to its surface. It is mainly produced by the continuous galvanizing process, that is, the coiled steel plate is continuously dipped in the galvanizing tank with molten zinc to make galvanized steel plate; alloyed galvanized steel plate. This kind of steel panel is also made by hot dip method, but it is heated to about 500℃ immediately after coming out of the tank, so that it can form an alloy film of zinc and iron. This galvanized coil has good paint adhesion and weldability.

Hot-dip galvanizing is the reaction of molten metal with an iron substrate to produce an alloy layer, thereby combining the substrate and the plating layer. Hot-dip galvanizing is to pickle iron and steel parts first. In order to remove iron oxide on the surface of iron and steel parts, after pickling, it is cleaned in an  ammonium chloride or zinc chloride aqueous solution or a mixed solution of ammonium chloride and zinc chloride.And then sent to the hot-dip plating bath. Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life.

Surface

(1) Normal spangle coating

During the normal solidification process of the zinc layer, the zinc grains grow freely and form a coating with obvious spangle morphology.

(2) Minimized spangle coating

During the solidification process of the zinc layer, the zinc grains are artificially restricted to form a spangle coating as small as possible.

(3) No spangle coating spangle-free

By adjusting the chemical composition of the plating solution, there is no visible spangle morphology and a uniform coating on the surface.

(4) Zinc-iron alloy coating

Heat treatment is carried out on the steel strip after passing through the galvanizing bath, so that the entire coating forms an alloy layer of zinc and iron. The appearance of this coating is dark gray, without metallic luster, and it is easy to pulverize during the violent forming process. Except for cleaning, coatings that can be painted directly without further treatment.

Production Process

Cleaning section: remove cold-rolling lubricating oil and iron powder on the surface of the strip. Cleaning before the entry looper facilitates stable tracking of the strip within the entry looper while avoiding dents and scratches.

Entrance looper section: When welding is stopped at the entrance, it provides an effective length of vertical looper to enable continuous production of the production line.

Furnace section: Vertical continuous annealing furnace, reaching the specified annealing cycle.

Galvanizing section: The strip is galvanized by immersing it in a molten zinc pot.

Skin pass mill and tension leveler section: improved performance.

Post-treatment section (passivation): Tandem twin-roller coater with furnace and cooling unit for coating with chromate solution for anti-white rust and fingerprints.

Outlet looper section: When the outlet section stops cutting, it provides an effective length of vertical looper to make the production line run continuously.

Product Advantages

01.Anticorrosive:13 years in heavy industrial areas,50 years in the ocean,104 years in the suburbs and 30 years in cities.

02.Cheap:The cost of hot-dip galvanizing is lower than that of other coatings.

03.Reliable:The zinc coating is metallurgically bonded to the steel and forms part of the steel surface,so the coating is more durable.

04.Strong toughness:The galvanized layer forms a special metallurgical structure that can withstand mechanical damage during transportation and use.

05.Comprehensive protection:Every part of the plated piece can be galvanized,and is fully protected even in depressions,sharp corners,and hidden places.

06.Save time and energy:Galvanizing process is faster than other coating methods.

Application

Galvanized steel coil products are mainly used in construction, light industry, automobile, agriculture, animal husbandry, fishery and other industries. Such as building roofs, highway guardrails, sheet metal processing, roof grilles, household appliance enclosures, ventilation ducts, chimneys, kitchen utensils, grain storage and transportation, frozen processing of meat and aquatic products, etc.

Packing And Shipping

Metal shell + airtight packaging + steel belt fixing. It will not be corroded by rain and sea water.