Steel products are often subject to galvanizing requirements, such as GALVANIZED G40 MIN COATING or GALVANIZED (MUST CONFORM TO G60 OR G90 COATING REQUIREMENTS). What exactly do G40, G60 and G90 refer to, and what are their corresponding galvanized coating thicknesses? We will explain them as follows:
G40, G60 and G90 are galvanized coating grades specified in the American ASTM A653 standard. Take G40 as an example: G40 means the total galvanized coating weight of both sides reaches 0.40 oz/ft², and the coating weight per single side is 0.12 oz/ft². 1 oz/ft² is equivalent to 1.7 mils , and 1 mil equals 25.4μm.
Key Conversions
1 oz/ft2=1.7 mils1oz/ft2=1.7mils
1 mil=25.4 μm1mil=25.4μm
G40:
Zinc coating weight: 0.40 oz/ft² (both sides combined)
Single-side equivalent: 0.12 oz/ft²
Calculated thickness: 0.12 oz/ft2×1.7 mils×25.4 μm=5.18 μm0.12oz/ft2×1.7mils×25.4μm=5.1816μm
G60:
Zinc coating weight: 0.60 oz/ft² (both sides)
Single-side: 0.20 oz/ft²
Thickness:0.20×1.7×25.4=8.64 μm0.20×1.7×25.4=8.636μm
G90:
Zinc coating weight: 0.90 oz/ft² (both sides)
Single-side: 0.32 oz/ft²
Thickness:0.32×1.7×25.4=13.82 μm0.32×1.7×25.4=13.8176μm
