A Secure AntiCorrosion Plan: Understanding the Galvanizing Process
Corrosion is the number one enemy of steel. It disfigures the material and affects overall reliability and safety. In big industries heavily dependent on metals, corrosion accounts for loss of income and other forms of liability. It may even cause a plant to shut down its operations. There are many ways to counter the threats and effects of corrosion. Adjusting the configurations of the storage environment and using inhibitors and coatings are only a few examples of what can be done. The most effective, however, is galvanizing. Galvanization is the process of reinforcing the integrity of steel. It is more comprehensive than the application of coatings. Processes involved ensure that intervening factors, such as changes in temperature and presence of impurities and electrolytes will not damage the material.
Material Cleaning The steel will undergo a thorough cleaning process before it undergoes heat treatment. The procedure is usually carried out using rotating abrasives and brushes. Special oils and modified sodium hydroxide is employed to remove scale, rust, and other contaminants. Heating Once cleaned, the steel will be heated to rid the material of remaining contaminants, excessive oxides, and oils. The heating process also ensures that molten zinc will adhere effectively to the metal. After being heated, the metal will proceed to the cooling phase. Galvanizing Proper As the steel is thoroughly cleaned, it is ready to undergo galvanization. Galvanizers will immerse the material into the molten zinc, which has a temperature of at least 450째C. The period of immersion depends on the weight and dimensions of the steel. After the immersion, galvanizers will then dip the coated steel into water for cooling. They may also use air-cooling methods. Compared to simple coating, galvanization provides thicker and more durable protection. The steel is not only protected from corrosion but also from immediate physical damages, such as abrasion and the effects of heavy loading.
SOURCES: http://ipnpr.jpl.nasa.gov/progress_report/42-69/69O.PDF http://depts.washington.edu/matseed/mse_resources/Webpage/Metals/metalprocess ing.htm http://www.wasatchsteel.com