news29 March 2026

Mistakes When Choosing Electro-Galvanised Steel Sheet (EG) For Steel Doors And Metal Furniture

Admin Phú Cường

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Mistakes When Choosing Electro-Galvanised Steel Sheet (EG) For Steel Doors And Metal Furniture

1. Overview: Why is EG steel sheet widely used in steel doors?

EG electro-galvanised steel sheet (EGI – Electro Galvanized Iron) is a type of cold-rolled steel coated with a galvanised layer by electro-galvanised method. The surface has a characteristic light blue color, is smooth, uniform, and very suitable for applications requiring high aesthetics.

In the steel door, metal furniture, and powder coating industries, this material is favored due to:

Smooth surface → good paint adhesion
Stable thickness → easy fabrication
High precision → suitable for mass production

However, precisely because of its “beautiful and easy-to-use” appearance, many people become complacent when choosing, leading to a series of serious mistakes.

You can refer to A-Z details about EG steel sheet (EG electro-galvanised steel) in the comprehensive article by Phu Cuong Steel Sheet & Steel: What is EG Steel Sheet? SECC, EG, EG Electro-Galvanised Steel – A–Z Summary & Applications in District 12

2. Mistake #1: Confusing EG steel sheet with galvanised steel sheet just because their surfaces look somewhat similar

This is the most common mistake in the market, especially among buyers who habitually use colloquial names instead of the correct material nature.

Many people just look at the bright, metallic, or slightly grayish surface and assume it's all “galvanised steel sheet”. In reality, within the group of metal-coated steel materials, EG steel sheet (often called EG electro-galvanised steel, EG, EGI) and hot-dip galvanised steel sheet (GI/HDG) differ in surface coating method, appearance, coating thickness, and intended use.

Because of this confusion, many fabrication workshops or purchasing units choose the wrong material from the start: if a beautiful surface is needed for painting, they take hot-dip galvanised; if better corrosion resistance is needed in harsh environments, they take EG. The result is products that do not meet expectations for aesthetics, durability, or cost-effectiveness.

2.1. Why do many people easily confuse these two types?

The first reason is that both are steel with a metallic coating, so when viewed with the naked eye, especially under warehouse lighting or when the goods are still in coil, they both give the impression of “brightly colored steel sheet”.

The second reason is that market terminology is often inconsistent. Many places generally refer to all types of coated steel as “galvanised steel sheet”, while in reality, the material used for steel doors, electrical cabinets, metal furniture, or powder-coated products is often electro-galvanised steel with a much smoother surface.

The third reason is that buyers often focus on price, nominal thickness, or steel sheet width, but do not ask thoroughly whether it is electro-galvanised or hot-dip galvanised, what purpose the coating serves, and whether the surface is suitable for painting and fine fabrication.

For more details, you can refer to this article: Comparing EG Steel Sheet, GA, Galvanised, Cold-rolled Steel, Hot-rolled – How Do They Differ?

2.2. Differences in appearance: similar from afar, clearly different upon close inspection

If observed closely, EG steel sheet usually has a smooth, fairly uniform surface, feeling “soft” and cleaner. This type is often highly valued in applications requiring surface aesthetics, especially when subsequent painting or powder coating is required.

Meanwhile, hot-dip galvanised steel sheet usually has an appearance characteristic of the hot-dip galvanised layer: the surface may show galvanised spangle effect (spangle - illustration below) or a more distinct granular surface feel depending on the product type, factory, and finishing technology.

For those unfamiliar with the material, they may still see the bright silver surface and assume it's just another version of EG.

In other words, if only superficially observed with the naked eye, especially without much experience with the material, buyers can easily mistakenly conclude that these two types only differ slightly in color or commercial name. But in reality, the difference lies not only in color but also in the coating structure and intended use.

2.3. Differences in coating nature

EG steel sheet (EG/EGI) is cold-rolled base steel coated with a galvanised layer by electro-galvanised method. This coating usually provides a beautiful, smooth, uniform surface and is suitable for parts requiring precise fabrication, stamping, welding, painting, or aesthetic finishing.

Galvanised steel sheet (GI/HDG) is usually steel coated with galvanised by hot-dip method. This type usually has a coating that prioritizes better corrosion protection under various usage conditions, but the surface is not always optimal for applications requiring high smoothness and aesthetic finishing like furniture or beautifully painted steel doors.

This is the core point: one type focuses on surface and fine fabrication, the other focuses on stronger corrosion protection. If this is not understood, material selection can easily deviate from the intended use.

2.4. Consequences of confusing EG with galvanised

In the first case, if a product requires a beautiful surface for powder coating, making steel doors, electrical cabinets, metal furniture details, or parts with high aesthetic requirements, but hot-dip galvanised is used, businesses may encounter problems such as:

Surface does not achieve expected smoothness
Increased effort for surface treatment before painting
Finished product looks coarser
Difficult to control uniformity during aesthetic finishing

In the second case, if a product is placed in an environment requiring higher corrosion resistance but EG is chosen just because of its beautiful surface, users may experience material degradation sooner than expected if usage conditions exceed the coating's suitable capacity.

In the third case, a mistake in the purchasing stage will lead to errors throughout the entire subsequent chain: incorrect fabrication process, incorrect coating expectations, incorrect surface treatment costs, and even incorrect quotations for the end customer.

2.5. How to identify to avoid confusion

To avoid this mistake, buyers should not just generally ask “galvanised steel sheet” or “bright steel sheet”. Instead, they need to ask clearly:

Is this electro-galvanised or hot-dip galvanised?
Is this material suitable for aesthetic painting or more for corrosion protection in outdoor environments?
Is the surface a smooth type used for steel doors, electrical cabinets, metal furniture, or a common galvanised type?
Does the supplier clearly describe the standard, origin, surface, and intended use?

If it is a manufacturing unit specializing in steel doors, powder coating, metal furniture, or mechanical parts requiring a beautiful surface, correctly identifying from the outset that one needs EG electro-galvanised steel instead of just generally saying “galvanised steel sheet” will help reduce many risks.

2.6. Conclusion of this mistake

The essence of the mistake is not in “incorrect naming”, but in equating two types of materials with somewhat similar surfaces but different functions. In the steel door and metal furniture industry, a mistake made right from the raw material selection step can affect the entire finished product quality, coating capability, and cost-effectiveness.

Therefore, instead of asking “is this steel sheet galvanised steel sheet?”, the more appropriate question should be: is this EG electro-galvanised steel or hot-dip galvanised steel, and is it truly suitable for my application?

➡ If EG is used for outdoor environments → it rusts quickly.

➡ If galvanised is used for products requiring a good paint finish → it is difficult to achieve aesthetic appeal.

3. Mistake #2: Not checking actual thickness

Many workshops only buy according to “nominal specifications” without actual measurement.

In reality, steel sheet always has thickness tolerance. For example:

Steel sheet 1.0mm may only be 0.92–0.95mm

This directly affects:

Steel door hardness
Load-bearing capacity
Product lifespan

Solution:

Use a micrometer to measure at multiple points
Request CO, CQ from the supplier

4. Mistake #3: Not paying attention to the coating

Not all EG steel sheets are the same.

Electro-galvanised coating can differ in:

Galvanised layer thickness
Adhesion
Surface uniformity

If the coating is poor:

Paint peels easily
Easily oxidizes after fabrication

5. Mistake #4: Choosing the wrong type of base steel

Many people only care about “EG” while ignoring the base steel.

In reality, EGI is produced from cold-rolled steel (CR steel), but:

Each factory has different quality
Different surface cleanliness

➡ This affects:

Bending strength
Stamping capability
Paint quality

6. Mistake #5: Not optimizing steel sheet width (causing large waste)

This is an extremely “costly” mistake but few people notice.

Many workshops use standard width steel sheet (1000mm, 1250mm) while products have large dimensions.

➡ Result:

Much material waste
Increased production costs

Solution:

Use large width steel sheet (1500mm or more)
Optimize cutting layout

7. Mistake #6: Not controlling the surface before painting

Although EG steel sheet has a beautiful surface, but if:

Scratched during transportation
Contaminated with oil or dust

➡ Powder coating will not adhere well.

➡ Leading to peeling after a short time.

8. Mistake #7: Choosing a supplier without fabrication capability

Many units only sell steel sheet without fabrication services.

This causes:

Must outsource → increased costs
Difficult to control quality

Meanwhile, if choosing a unit with available:

Coil unwinding
Steel sheet slitting
Bending – stamping

➡ Can optimize costs and synchronize quality.

9. Conclusion

Choosing EG steel sheet is not just choosing “material type”, but choosing the right technical specifications, the right purpose of use, and the right supplier.

Just making one of the above mistakes, the cost of error correction or warranty can be much higher than the initial material cost.

10. Phu Cuong Steel Sheet – Leading Reputable Large Width Steel Sheet Distributor

Phu Cuong Steel Sheet – Accompanying Every Construction Project

Not only supplying materials, we focus on helping customers choose the right type of steel sheet according to the purpose of use, limit technical errors from the beginning – especially in the steel door, metal furniture, electrical cabinet, and precision mechanics industries.

We specialize in supplying material lines:

Electro-galvanised steel sheet EG (EGI), GA
Galvanised steel sheet (GI) with diverse coating thickness
Cold-rolled steel sheet, steel plate, steel coil
Especially: large width steel sheet from 1500mm or more – helps reduce material waste during fabrication

Core advantages of Phu Cuong Steel Sheet:

Beautifully flat cut products, correct thickness, correct specifications
Clean surface, limited scratches – suitable for powder coating
Billet source from large factories, full CO, CQ
Competitive prices in Ho Chi Minh City, especially District 12 area
Proactive delivery by private truck – optimize logistics costs

On-site fabrication services – helps reduce costs and control quality:

Coil unwinding according to required specifications
Sheet cutting (flat cutting) precisely according to size
Steel sheet slitting (slitting) into small widths
Bending – stamping – forming according to technical drawings
Steel sheet fabrication for the production of steel doors, electrical cabinets, metal furniture

With modern machinery systems and a technical team knowledgeable in drawings, we not only sell materials but also act as a technical solutions provider for manufacturing businesses.

Quality builds the brand.

Contact information:

Address: 2177C–2177D QL1A, P. Đông Hưng Thuận, Q.12, TP.HCM
Phone: 0933 919 899
Email: tonthepphucuong@gmail.com
Website: tonthepphucuong.com

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