How is Hot Dip Galvanized Sheet Made?
Hot-dip galvanized Hair Kg Price
Hot-dip galvanizing, abbreviated as SDG, is made to protect the steel. It is important that the materials to be used in sectors such as automotive and construction do not rust for a long time. These materials are coated to resist corrosion. After zinc coating, the surface appearance, coating thickness, mechanical properties and corrosion behaviors change. In this way, the material becomes much better quality.
Before the hot dip galvanizing process, it is necessary to prepare the material. After the process is finished, the material that is approved by the quality control is ready to be shipped. Galvanizing process steps are as follows:
Hot Dip Galvanizing
For the best coating of the materials, the surface must be clean. If there are unwanted residues on it, there will be roughness after coating. For this reason, surface cleaning processes are applied to the material. It is difficult to acidify chemical substances such as oil and grease on the surface of the material. In order to make this process much easier, the material is put into the degreasing bath. Thanks to this process, which is also called alkaline bath, the dirt layer disappears. Alkaline salts used during degreasing are sold in powder or crystal form. It is prepared by dissolving in water according to the instructions for use.
Surface Cleaning with Acid
If there is rust on the material, it will not be destroyed by degreasing. The oxide layer on the metal will prevent the iron from reacting with the zinc during galvanization. For this reason, it is thrown into the acid bath to get rid of the rust and oxide layer. Hydrochloric acid is used for surface cleaning with acid. The acid value of the pool is measured at regular intervals to ensure that it remains at the desired rate. Iron immersed in the pool may interact with the acid. In order to protect the iron, an inhibitor, which is a substance that does not affect the reaction rate, is added as it enters.
The material should be removed from the pool where it is thrown on time. This stage galvanize coating is of critical importance. If it is left too much, abrasions can be observed on the surface. Since the rust rate in each material is not the same, it must be mounted on different hangers. It should be constantly checked throughout the application and the rust-free materials should be removed from the bath. It is worked at room temperature so that harmful gas does not come out of the acid bath.
The rinsing process is done to purify the hydrochloric acid remaining on the surface of the material. The material is immersed in a water-filled pool and removed. Thus, the material is prepared for the next stage. This process takes an extremely short time, but it must be done carefully.
Before galvanizing steel It is immersed in a flax bath to prevent its surface from rusting. During hot galvanizing, a rapid reaction between iron and zinc is required. Thanks to the fast reaction, a smoother surface is obtained. The Flax process will also destroy the residues left in the material after the previous processes. Powders adhering to the material surface in the flax bath are useful during galvanization. In this way steele zinc reacts more easily.
After the flax process, the drying stage is started. This stage is important in terms of job security. If the material is not dried, it may explode when immersed in the pool. The explosion will cause zinc reduction and environmental pollution. During the drying period, the flux solution in the material is evaporated. In this way, a thin flux layer remains on the surface.
The materials, which have passed the preparation processes successfully and approved by the quality controllers to be suitable for galvanization, are brought to the coating area. Here, it is immersed in the zinc pool for a certain period of time and covered. How long the material will stay in the pool will be calculated depending on its weight and wall thickness.
For coating to occur, the material must remain in the pool until the temperature reaches the bath temperature. During the coating of the material, chemicals from previous processes and a thin oxide layer form on the surface of the pool. Remains on the surface must be removed before the material is taken out. Thus, the quality of the obtained coating does not decrease.
Galvanization After the finished material is taken out of the bath, which reaches 400 degrees, it starts to cool rapidly. The decrease in temperature causes the zinc cover on the surface to thicken. Cooling can be done in water, air or oil. If cooling is to be done in the air, the environment must be free from dust. Otherwise, this application will not give good results. The water cooling process provides very fast cooling. In this case, roughness occurs on the surface. If a very smooth surface is desired, cooling in water should not be done. However, partial water cooling can be applied by cooling the part with both water and air. In this case, the inner and outer surfaces of the part will have a glossy appearance.
The purpose of quenching is to provide a better adhesion of the coating to the material. The coating will be smoother if a little soap and oil is added to the water. Corrosive salts from the flux layer may come into the water used, so it should be changed frequently.
Hot Dipped Galvanized Kg Price
hot dip galvanized price per kg It is determined depending on the type of material and the processes to be applied. There may be fluctuations in prices depending on the movements in the exchange rate and market demand. You can get a kilogram price according to the wall thickness of your material. If you want a high amount of material to be covered, the kilogram price will be more affordable. You can contact us to get information about the price.