The criteria for the thickness of the galvanised layer of galvanised pipes are governed by the following provisions.
1. When the thickness of the workpiece is greater than or equal to 6 mm, the average thickness of the galvanised layer shall be greater than 85 microns.
2. For workpiece thicknesses between 3 mm and 6 mm, the average thickness of the galvanised layer shall be greater than 70 µm and the partial thickness greater than 55 µm.
The average thickness of the galvanised layer shall be greater than 70 microns and the partial thickness shall be greater than 55 microns.
3. For workpiece thicknesses less than 3 mm but greater than .5 mm, the average galvanised layer thickness shall be greater than 55 microns and the local thickness shall be greater than 45 microns.
4. It should be noted that these standards do not apply to the thickness of galvanising on centrifugally separated plated and cast iron parts.
Galvanised thickness of cast iron parts
5. For pipes with wall thickness > 6 mm, the average thickness of the coating is 85 um.
6. The thickness of electro-galvanised zinc is also regulated by international and national standards.
7. For hot-dip galvanised square tubes, the thickness requirements are: for square tubes with a wall thickness of less than or equal to 3mm, the thickness of the galvanised layer shall be
For square pipes with wall thickness less than or equal to 3mm, the thickness of galvanised layer shall be more than or equal to 15 um; for square pipes with wall thickness greater than or equal to 3mm, the thickness of galvanised layer shall be more than or equal to 25m.
