# What is a G40 coating?

## What is a G40 coating?

The minimum protective coating requirement of ASTM C645 is G40. To explain the meaning of this coating designation, the alpha character “G” indicates that the coating is galvanized (zinc-based), and the numeric character refers to the weight of zinc on the surface of the steel sheet in ounces per square foot units.

What is the difference between G40 and G90 galvanized?

G90 galvanized steel has a longer service life than G60, G40, and G30 galvanized steel, because G90 galvanized steel has a heavier coating weight of zinc applied to it at 0.90 oz/ft^2 as opposed to G60 galvanized steel at . 060 ox/ft^2 and so on.

How long will a galvanized G40 G60 G90 coating last?

documentation included the information that a G40 coating has a minimum thickness of 9.5 microns of zinc on each surface. The life expectancy of this material would therefore be at least 95 years (compared to 140 years for the G60 coating).

### What is G60 coating?

A G60 coating refers to a total of 60 grams per square foot. Approximately 30 per side. Some JIS specifications may call for a hot rolled substrate. Some steel mills REFUSE to use any hot rolled substrate. You must also understand that JIS is a general industry standard.

What is G40 galvanized?

The Inch-Pound term G40, a designator used only for hot-dip galvanized sheet, is defined by A 653/A 653M as total coating weight, both sides. It has approximately 0.23 oz /ft2 (70 g/m2) of coating on each side of the strip, if the coating is equally divided.

How thick is G60 galvanized coating?

approximately 0.5 mil
Galvanizing thicknesses are identified by different G numbers. The G60 designation indicates a zinc coating of 0.60 oz/ft2 (total on both sides) or a thickness of approximately 0.5 mil (1 mil = 0.001 inch) on each side of the steel.

#### What does G40 coating mean?

In order to explain the meaning of this coating designation, the letter ‘G’ indicates the coating is galvanized or zinc-based and the ‘40’ refers to the total weight of zinc on the surfaces of the steel sheet in grams per square meter or ounces per square foot.

What is ASTM c645 G40 coating?

The minimum protective coating requirement of ASTM C645 is G40. In order to explain the meaning of this coating designation, the letter ‘G’ indicates the coating is galvanized or zinc-based and the ‘40’ refers to the total weight of zinc on the surfaces of the steel sheet in grams per square meter or ounces per square foot.

What is G40 G60 and G90 steel?

G30, G40, G60 AND G90: UNDERSTANDING ZINC-BASED COATING WEIGHTS EXECUTIVE SUMMARY Zinc-coated, or hot-dipped galvanized, steel is a widely used material in numerous applications, thanks to its corrosion-resistance, strength and relatively inexpensive cost.

## What is the minimum coating weight required for G90?

The total of the average coating weights of each side must be equal to or greater than the speciied minimum for that designation. For G90, the total of the per-side average coating weights must be 0.90 oz/ft2.