steel expanded metal mesh

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.

Out-of-line annealing means that the recrystallization annealing of hot or cold rolled steel plate is carried out in the bottom type annealing furnace or cover type annealing furnace before entering the hot plating wire line, so that there is no annealing process in the galvanized line. The steel plate must maintain a clean active surface of pure iron, free of oxides and other dirt, before hot dip galvanizing. In this method, the annealed surface oxide sheet is first removed by pickling method, and then coated with a layer of zinc chloride or a mixture of ammonium chloride and zinc chloride solvent for protection, so as to prevent the plate from being oxidized again.