The main factors affecting thickness of hot-dip galvanizing coating include: matrix metal composition, surface roughness of steel, content and distribution of active elements silicon and phosphorus in steel, internal stress of steel, number of scale of workpiece, hot dip galvanizing process. Current world and our country hot galvanizing standard all divides section according to steel thickness, zinc plating layer tie thickness and partial thickness should arrive corresponding thickness, in order to determine zinc coating's anticorrosion function. Different thickness of steel workpiece, to achieve thermal balance and zinc and iron alternating balance of the time required, the composition of coating thickness is also different. The average thickness of the shandong hot zinc coating in the specification is the empirical value of industrial production according to the above-mentioned galvanizing mechanism. Therefore, the ISO specification, American ASTM specification, Japanese JIS specification and Chinese specification have slightly different requirements on the thickness of zinc coating.

Now hot galvanizing technology development has got new enhancement, to produce technology to have new requirement again.

(1) the unit is developed towards high yield

Since the 1990s, the hot-dip galvanizing units built in shandong have been developed towards high yield. There are about 60 hot-dip galvanizing units with a global capacity of 300,000 t/a, and their total production capacity exceeds 28 million t/a.

(2) unit specialization

Zinc-coated passenger cars and building materials use different types of unit production, unit technology, monomer equipment and furnace selection is more reasonable, so that the contribution role is significant, product cost reduction.

(3) emphasize the cleaning of substrate appearance

In recent years, the automobile plate galvanizing unit built by using lye electrolysis cleaning and full radiation pipe heating furnace has been economically increased. In order to reduce the capital contribution, the building material type galvanizing unit chooses the modified sengidal process more often, but the unit sets up the cleaning section more frequently, makes the base plate appearance is cleaner, the product quality is better.