Hot dip galvanizing: Corrosion control and prevention is an essential factor in the economic utilization of iron and steel. Every year rust and corrosion cause several billion US$ in damages to surfaces, buildings, plants and equipment all over the world. Protective paints and coatings provide a certain measure of protection over a limited period, but these usually call for repeated application, resulting in additional costs. When coatings have been broken, corrosion begins at the steel’s exposed area, spreading rapidly beneath the protective coating film.

Hot dip galvanizing is a process in which metal is immersed into molten zinc to form a protective layer which completely covers the steel surface and seals it metallurgically to protect from the corrosive actions of its environment. This ensures greater resistance to corrosion and rust over a much longer period than any other form of coating. Wherever there might be minor damages in the sealing coat of zinc, protection of the steel is still maintained by the cathodic or sacrificial action of the surrounding galvanized coating. Therefore, for most kinds of steel products, galvanizing provides the lowest long-term costs and in many cases also the lowest initial costs, compared to any other form of corrosion control and prevention.

Hot dip galvanizing is especially useful for metal works and surfaces that are subject to wear and tear, such as used in walkways, ladder rungs, chains, handrails, pipes, lamp poles, etc. In particular it is most useful in enabling structural works to achieve outstanding toughness and resistance to corrosion. Here you can also find more details about the steel galvanizing process of Siam Steel Galvanizing Co., Ltd. and its daughter companies. We execute our customers' orders to meet the following standards: - American standards (ASTM) A123; A153/A153M - British standards BS729; BS/EN/ISO 1461 - Australian standards AS 1214; AS/NZS 4680 - Japanese standards JIS H8641 & 9124 - German standard DIN50976

The parts are placed in a basket, dip coated in molten zinc and the excess zinc is then removed via a centrifuge. The recommended minimum size of a bolt or nut to be coated with this method is M20 or larger. The zinc coating on threads should not be subject to any cutting, rolling or finishing tool operations. However, threads in nuts may be tapped or retapped by the customer after the galvanizing process.

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