Hot-dip galvanized steel grating requirements:
a) The surface of the steel grating made of carbon structural steel should be hot-dip galvanized.
b) The surface of the components should be treated before hot-dip galvanizing the steel grating to ensure that the metal surface is clean. Pickling can be used for surface cleaning, but excessive pickling should be avoided. For surface dirt that cannot be pickled off, such as carbon film , Oil stains, paint, welding slag, etc. should be removed before pickling.
c) The hot-dip galvanizing of the steel grating shall ensure that the surface of the component is dry and no aqueous solution or other moisture shall remain.
d) The zinc bath used for hot dip zinc should be mainly composed of molten zinc liquid, and the total content of impurities (except iron and tin) in the molten zinc should not exceed 1.5% of the total mass.
e) The hot-dip galvanized thick surface of the steel grating should be smooth, free of dripping, roughness and zinc thorns, no peeling, and no residual solvent residue.
f) When the thickness of the loaded flat steel is not less than 5mm, the average zinc layer weight after galvanizing should not be less than 610g/㎡, and the average thickness should not be less than 85μm. When the thickness of the loaded flat steel is less than 5mm, the average zinc layer weight after zinc immersion is not less than 460g/㎡, and the average thickness is not less than 65μm. The weight of the zinc layer with centrifugal treatment should be no less than 395g/㎡, and the average thickness should be no less than 55μm. The quality and requirements after galvanizing should meet the requirements of GB/T13912-2002.
g) After the steel grating is hot-dip galvanized, it should not be piled up when the surface is still hot and wet. The steel grating should be centrifuged or exploded immediately after being taken out of the hot-dip galvanized zinc bath. Excess zinc.
h) After hot-dip galvanizing, the total area of the missing plating surface of each steel grating shall not exceed 0.5% of the total surface area, and the area of each missing plating surface shall not exceed 10cm2. If there is a missing plating surface, hot Repair the missing surface by spraying zinc, coating zinc-rich paint or melting zinc alloy. For specific methods, refer to the provisions of GB/T13912-2002. The repair layer should be able to provide sacrificial anode protection to the steel during the use of the steel grating. The oxide scale and other dirt in the missing plating area should be removed before the repair.