G90 Galvanized Steel

G90 galvanized steel is a durable galvanized steel product. “G+number” is used to describe the zinc coating thickness of galvanized steel according to ASTM Standards (ASTM-A525 or ASTM-A653/A653M). Wanzhi Steel specializes in the production of G90 galvanized steel, which can be processed into coils, plates, as well as pipes. We not only have a good reputation but also have competitive prices. Therefore, You are welcome to visit our factory. Over the years, we have established a multilingual team with rich export experience. You are welcome to contact me for a free quote.

Ⅰ. G90: Letters and numbers explained

The “G” here refers to galvanizing, and the number refers to the weight of zinc on the surface of the steel sheet, such as G30, G60, G90, and G185. The higher the number, the thicker the zinc coating. For example, G90 galvanized steel has a zinc coating weight of 0.9 ounces per square foot. While G60 means the dual-sided coating weight is 0.6 oz/ft². The following will discuss the difference between the two.

Ⅱ. Commonly Used Codes, Meaning of Letters

There are some commonly used codes, such as DX51D+Z275. In short, you may find the codes on the package of steel coils or sheets.

DX51D+Z275 is a designation for hot-dipped galvanized steel according to European standards.

1. The first letter “D” means flat steel for cold forming,

2. And the “X” here means that the rolling state of the substrate is not specified. If the letter is C, it means that the substrate is specified as a cold-rolled substrate; if the letter is D, the substrate is specified as a hot-rolled substrate.

3. Besides, the number (51, 52, 53, 54, etc) indicates the serial number of the steel grade, and “51” is for general uses.

4. The “D” after the number means hot-dip galvanizing. Z275 refers to the zinc coating thickness of 275 g/m². Except for zinc coating, you may find galvalume coating (AZ), ZAM coating, etc.

Ⅲ. What is the difference between G40 and G90 galvanized?

G90: Galvanized steel with 0.9 ounces of coating per square foot. It can be used in areas with high humidity or other extreme environmental factors.
While G40: Represents Galvanized steel with 0.4 ounces of coating per square foot. It is usually used in areas with milder environments.

Ⅳ. What is G90 galvanized steel?

It is a hot-dip galvanized, cold rolled steel sheet with a durable protective coating. It is suitable for applications where corrosion is a concern and where simple bending or moderate forming is involved.

G90 galvanized steel can be bent in any direction (within an acceptable bend radius) at room temperature without cracking. Typically this material is available with a G:90 (or Z275) coating and can also be available with a G:60 (or Z180) coating.

Ⅴ. Z275 Galvanized Steel

According to the EN 10346 standard, Z+number is used to specify the zinc coating thickness of hot-dip galvanized products. Z here means zinc, and the number refers to the zinc coating weight. For example, Z275 means the weight of zinc on both sides of the steel surface is 275 grams per square meter. While Z140 or Z14 is often used to describe the zinc coating weight of 140 g/m². Also, the higher the number, the thicker the zinc coating.

Ⅵ. G90 VS Z275 Galvanized Steel

Let’s convert them to the same units. 1 ounce/sq ft is about 305.15 g/m². Then 0.9 ounces/sq ft is about 275 g/m². Therefore, G90 and Z275 actually describe the same zinc coating thickness of galvanized steel. “G+number” is commonly used in the USA and provides a basic level of corrosion protection for steel. While “Z+number” is commonly used in Europe and other countries.

Some customers would like to use the unit of microns (μm) to calculate the thickness of the zinc layer. The density of zinc is 7.14 grams/cm³.  In terms of the Z275 galvanized sheet,  275/7.14=38.5154 cm³=38515.4 mm³, that is, the average thickness per square meter is 38.5154 μm (total both sides). Below is a table for your reference.

EN 10346 Standard	ASTM Standard	Ounce/sq ft (both sides)	Gram /m2 (both sides)	Microns (one side)	Mils (one side)
Z90	G30	0.3	90	6	0.25
Z120	G40	0.4	120	9	0.34
Z180	G60	0.6	180	13	0.51
Z275	G90	0.9	275	19	0.76
Z350	G115	1.15	350	25	0.97

Ⅶ. G90 VS G60 GI Steel

Galvanization refers to the process of applying a protective zinc coating to steel or iron to prevent rusting. The letters “G” followed by a number (like G60 or G90) indicate the thickness of the zinc coating. G90 is with a zinc coating weight of 0.9 ounces per square foot. Meanwhile, G60 has a zinc coating weight of 0.6 ounces per square foot. Generally, the thicker the zinc coating, the better the corrosion resistance, and durability. Obviously, G90 galvanized steel provides a thicker and more durable zinc coating compared to G60 galvanized steel, making it more durable and long-lasting.

Ⅷ. Minimum recommendation for outdoor use: G90 (Z275) GI steel

Galvanized steel should avoid contact with lead or copper, as this will accelerate corrosion. In addition, galvanized steel is not recommended for use near seawater (chlorides will accelerate corrosion) or other harsh corrosive environments.

For all outdoor applications where the Galvanized material is bare and not painted a minimum G:90 (Z275) is recommended, and for additional protection in corrosive or polluted environments, heavier coated products should be considered.

Ⅸ. Uses of G90 Galvanized Steel

G90 galvanized steel is a kind of high zinc-coated steel. Due to its excellent corrosion resistance, it is widely used, summarized as follows:

1. Roofs, and wall panels.

2. Beams, columns, and purlins.

3. Storage tanks, silos, and sheds.

4. Feed boxes, barns, and poultry houses.

5. Auto parts with high corrosion resistance requirements.

Ⅹ. G90 GI Steel Manufactor – Wanzhi Steel

Wanzhi Steel offers both hot-dipped (30-275 g/m²)and electro-galvanized steel (not more than 30 g/m²). Furthermore, there are four main types of spangles: zero, mini, regular, and big. The thickness is available from 0.12 to 4mm and the width ranges from 600 to 2,000mm. In addition, we also produce gavalume steel and stainless steel products. You are welcome to visit our production workshop online.