How to distinguish and identify the difference between hot dip galvanizing and cold dip galvanizing

The difference between the first processing technology is:
Hot-dip galvanizing requires a certain amount of time to degrease, pickle, passivate, soak, and air-dry the steel parts into the molten zinc liquid.

Cold spray zinc is also called phosphating treatment. It uses electrolytic equipment to degrease, pickle and passivate the steel parts and then puts them into an aqueous solution composed of zinc salts, and connects the negative stage of the electrolytic equipment; it is placed on the opposite door of the steel parts. The zinc plate is connected to the positive stage of the electrolysis equipment, connected to the power supply, and the current is moved from the positive stage to the negative stage, and the zinc plate will be igneous layer by layer on the steel parts. Differences in appearance: the phosphating surface is smoother and brighter, and the electroplating process layer using colorful passivation process is also mainly light green, which is colorful. The plating process layer using white passivation process will appear bluish white or white with green light. The coating of white passivation process will appear slightly colorful when viewed from a certain angle with the sun. The corners and edges of complex steel parts can easily cause "electrical burning" and become dull. The zinc layer at this location is too thick. At the inner corner line, it is easy to produce a blind area of current, resulting in a dim area of undercurrent. The zinc layer in this area is thin. The steel parts generally have no problems such as zinc tumors and agglomeration. The appearance of hot-dip galvanizing is slightly rougher than phosphating and is silver in color. The appearance is easy to cause process water flow and a small amount of dripping, especially on one side of the steel piece. However, the zinc layer of hot-dip galvanizing is several times thicker than that of phosphating treatment, and its corrosion resistance is several times that of phosphating treatment. Differences between hot-dip galvanized products:

1. The inner and outer walls of hot-dip galvanized steel pipes are hot-dip galvanized, while hot-dip galvanized steel pipes only have hot-dip galvanized surfaces;

2. The cold coating is even and the thickness is too thin; the hot coating is too thick and the thickness is uneven.

3. Cold-dip galvanizing has a bright appearance, while hot-dip galvanizing has a darker tone.

11. The cold coating is thinner and has weak corrosion resistance; the hot coating is several times thicker than cold spray zinc and has a penetration layer with coarse-grained metal materials, so it has good corrosion resistance.

4. The surface of hot-dip galvanized steel pipes looks brighter and smoother; the surface of hot-dip galvanized steel pipes is not as delicate and bright as that of cold-sprayed galvanized steel pipes. The surface of hot-dip galvanized steel pipes looks like there are some uneven bumps and dents, and the surface does not shine. , not very reflective.