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The principle difference between hot-dip galvanizing and cold galvanizing

  • Author:Zoe Jia
  • Release on:2023-08-02
The principle difference between hot-dip galvanizing and cold galvanizing

Hot-dip galvanizing through the principle of zinc anti-atmospheric corrosion, to steel and other materials electrochemical protection, the surface of zinc carbonate protective film can slow down the speed of zinc corrosion, even if destroyed, will form a zinc film again.

Cold galvanizing is the use of chemical methods, the zinc alloy is separated into zinc ions, has been attached to the surface of steel, the new layer formed in this way is generally thinner, steel in general, easy to produce rust.

The difference between the appearance of hot-dip galvanized and cold-dip galvanized

The outer surface of cold galvanized is relatively smooth and bright, the electroplating layer of the color passivation process will be yellow-green, the electroplating layer of the white passivation process will be blue-white, and the general cold galvanized steel pipe has only a small amount of zinc layer at both ends, and there is no galvanized layer further inside.

The outer surface of hot-dip galvanized is rough, darker in color, and generally silvery-white, because the production process causes some water lines and dripping tumors on the surface, and the surface does not emit light and will not reflect. The hot-dip galvanized steel pipe has a complete galvanized layer inside and outside.

The source and function difference between cold galvanizing and hot galvanizing

Hot-dip galvanizing originated in the cold-rolled strip industry more than a hundred years ago, and is a relatively old hot-dip plating method, which is mainly used in metal structural facilities in various industries.

As a new type of electroplating, cold galvanizing is the best material to replace hot galvanizing, and most of the cold galvanizing solvents do not contain toxic solvents and heavy metals such as toluene and ketones. Cold galvanizing as a thick film material, has good thixotropy, after full stirring, add a small amount of thinner, can be coated construction, generally in the normal temperature environment for operation. Cold galvanizing construction projects can reduce the emission of waste water, waste gas, etc., reduce energy consumption, have a greater guarantee for the personal safety of construction personnel, is conducive to environmental protection, and has high social benefits.

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