Good galvanized wire, plating thickness of 3- 4 mm, zinc adhesion should be less than 460 grams/m, that is, the average thickness of zinc layer is not less than 65 microns. When the thickness of plated parts is greater than 4 mm, the zinc adhesion should not be less than 610 g/m, that is, the average thickness of zinc layer should not be less than 86 microns. Standard galvanized wire coating must be uniform, galvanized layer basically uniform with copper sulfate solution test etching five times no dew iron. For standard galvanized wire coating adhesion requirements, the zinc layer of plated parts should be firmly combined with the basic metal and have enough adhesion strength, after hammer test does not fall off, not convex.

This process has no mold, low processing cost, easy forming, can process a variety of shapes and other characteristics are widely used. But the products of the guardrail are powder impregnated plastic. According to whether it needs heating, it is divided into hot dipping and cold dipping. According to the raw materials of dipping, it can be divided into liquid dipping and powder dipping. Hot-dip galvanizing, as a metal anticorrosion method, is usually to put the steel structure to be derusted into the zinc liquid at about 500℃, so that the zinc layer is attached to the surface of the steel structure.