Hot-dip galvanizing: also known as hot-dip galvanizing and hot-dip galvanizing: it is an effective method of metal anticorrosion, mainly used in metal structural facilities in various industries. It is to immerse the rust-removed steel parts in a molten zinc solution at about 500 ° C, so that the surface of the steel parts adheres to the zinc layer, so as to achieve the purpose of anti-corrosion.
Cold galvanizing: It is electro-galvanizing, with a small amount of zinc, only 10-50g/m2. It is a process of using electrolysis to attach a layer of metal film to the surface of metal or other materials. The process of forming a uniform, dense and well-bonded metal layer can prevent corrosion, improve wear resistance, electrical conductivity, reflectivity, and enhance aesthetics.
The difference between hot-dip galvanizing and cold galvanizing:
1. Different corrosion resistance, hot-dip galvanizing is dozens of times that of cold galvanizing.
2. The operation methods are different: hot-dip galvanizing is zinc plated in a molten zinc solution of 450-480 degrees, and cold galvanizing is zinc plated by electroplating or other methods at room temperature.
3. The thickness of the galvanized layer is different, and the thickness of hot-dip galvanizing is much larger than that of cold galvanizing.
4. The surface smoothness is different, and the appearance of cold galvanized is smoother and better than that of hot-dip galvanized.
5. The price is different, the price of hot-dip galvanizing is higher than that of cold galvanizing.
6. Cold galvanizing can only be plated on one side, and hot galvanizing should be fully plated.
7. The adhesion is different, and the adhesion of cold galvanizing is not as good as that of hot-dip galvanizing.
8. The charging standards are different. Hot-dip galvanizing is charged according to the thickness of the material, and most of the cold galvanizing is charged according to square meters.
The main application scope of hot-dip galvanizing process: industry, construction, power facilities, chemical facilities, machinery manufacturing, petroleum, municipal facilities, agricultural facilities, communication facilities, fire protection facilities, railways, highway transportation facilities and other fields.
2, What is the difference between galvanized steel and aluminized steel?
The density of galvanized sheet is 7.85 tons/m*m*m, which means that 1.0mm sheet thickness 1 square meter weighs 7.85Kg, and 0.75mm sheet thickness 1 square meter weighs 5.8875Kg.
The thickest galvanized layer is 80 grams per square meter, 160 grams on both sides, and the most common is 50 grams of galvanized, 100 grams on both sides. This way a simple relationship can be known.
Zinc plate density calculation method = iron plate weight + galvanized layer weight For example, 1 mm thick galvanized plate, the plate weight is 7.85 kg, the galvanized layer weight is 2*0.05 kg, the weight per square meter is 7.95 kg, other specifications are also Calculate the same. The weight of the galvanized sheet is slightly heavier than that of the ordinary iron sheet, and the thickness of the coating is different. The price of the different coating thickness should be different.
Galvanized sheet is mainly used in construction, light industry, automobile, agriculture, animal husbandry, fishery and commercial industries. The construction industry is mainly used for the manufacture of anti-corrosion industrial supplies and panels, roof grilles, balcony panels, window sills, newsstands, warehouses, rolling shutters, heaters, rainwater pipes, etc. used in civil construction houses.
The light industry uses it to manufacture household appliance housings, civil chimneys, kitchen utensils, etc., the automobile industry is mainly used to manufacture corrosion-resistant parts of cars, etc.; agriculture, animal husbandry and fishery are mainly used for grain storage and transportation, and frozen processing of meat and aquatic products. Utensils, etc.; commercial use is mainly used as storage and transportation of materials, packaging tools, etc.
Household appliances such as refrigerators, washing machines, switch cabinets, air conditioners, microwave ovens, bread machines, copiers, vending machines, electric fans, vacuum cleaners, etc. also use galvanized sheets.
According to the production and processing methods, it can be divided into the following categories:
①Hot dip galvanized steel sheet. The sheet steel is immersed in a molten zinc bath, and a sheet of zinc is adhered to its surface. At present, it is mainly produced by continuous galvanizing process, that is, galvanized steel plates are made by continuously immersing rolled steel plates in a plating tank where zinc is melted;
②Alloyed galvanized steel sheet. This kind of steel plate is also made by hot dip method, but immediately after it is out of the tank, it is heated to about 500 ℃ to form an alloy film of zinc and iron. This galvanized sheet has good paint adhesion and weldability;
③ Electro-galvanized steel sheet. The galvanized steel sheet produced by the electroplating method has good workability. However, the coating is thin, and the corrosion resistance is not as good as that of the hot-dip galvanized sheet;
④Single-sided and double-sided differential galvanized steel. Single-sided galvanized steel sheet, that is, a product that is galvanized on only one side. In welding, painting, anti-rust treatment, processing, etc., it has better adaptability than double-sided galvanized sheet.
In order to overcome the disadvantage of not being coated with zinc on one side, there is another galvanized sheet coated with a thin layer of zinc on the other side, that is, double-sided differential galvanized sheet;
⑤Alloy and composite galvanized steel sheet. It is made of zinc and other metals such as aluminum, lead, zinc, etc. to make alloys or even composite plated steel plates. This kind of steel plate not only has excellent anti-rust performance, but also has good coating performance;
Reference: Baidu Encyclopedia – Galvanized Sheet
3, Galvanized steel material
Galvanized steel is non-toxic, but cyanide in the galvanizing solution is highly toxic.
Galvanized sheet refers to a steel sheet plated with a layer of zinc on the surface. Galvanizing is a frequently used economical and effective method of rust prevention, and about half of the world’s zinc production is used in this process.
There are two types of zinc plating solutions: cyanide baths and cyanide-free baths. The cyanide bath is divided into microcyanide, low cyanide, medium cyanide, and high cyanide. Cyanide-free baths include alkaline zincate baths, ammonium salt baths, sulfate baths, and ammonia-free chloride baths.
The cyanide zinc plating solution has good uniform plating ability, and the obtained coating is smooth and delicate, and has been used for a long time in production. However, due to the high toxicity of cyanide and serious environmental pollution, low-cyanide, micro-cyanide and cyanide-free zinc plating solutions have been used in recent years.
Galvanized steel sheets can be divided into the following categories according to production and processing methods:
1. Hot-dip galvanized steel sheet. The sheet steel is immersed in a molten zinc bath, and a sheet of zinc is adhered to its surface. At present, it is mainly produced by continuous galvanizing process, that is, galvanized steel plates are made by continuously immersing rolled steel plates in a plating tank where zinc is melted;
2. Alloy galvanized steel sheet. This kind of steel plate is also made by hot dip method, but immediately after it is out of the tank, it is heated to about 500 ℃ to form an alloy film of zinc and iron. This galvanized sheet has good paint adhesion and weldability;
3. Electro-galvanized steel sheet. The galvanized steel sheet produced by the electroplating method has good workability. However, the coating is thin, and the corrosion resistance is not as good as that of the hot-dip galvanized sheet;
4. Single-sided and double-sided differential galvanized steel. Single-sided galvanized steel sheet, that is, a product that is galvanized on only one side. In welding, painting, anti-rust treatment, processing, etc., it has better adaptability than double-sided galvanized sheet. In order to overcome the disadvantage of not being coated with zinc on one side, there is another galvanized sheet coated with a thin layer of zinc on the other side, that is, double-sided differential galvanized sheet;
5. Alloy, composite galvanized steel sheet. It is made of zinc and other metals such as aluminum, lead, zinc, etc. to make alloys or even composite plated steel plates. This kind of steel plate not only has excellent anti-rust performance, but also has good coating performance;