Galvanised steel coatings are celebrated for their longevity, durability, and cost-efficiency in preventing corrosion. The choice between pre-galvanised and hot-dip galvanised steel depends on your specific project requirements and intended application. RHS Steel Supplies offers a diverse range of steel products to meet your unique needs.
What is Galvanising?
Before exploring the differences between pre-galvanising and hot-dip galvanising, it's essential to understand the galvanising process itself. Galvanising involves applying a zinc coating to metals like steel or iron to protect against rust and corrosion. This zinc layer acts as a sacrificial barrier, enhancing the metal's durability and lifespan. While galvanised coatings cannot prevent corrosion indefinitely, they significantly extend the life of steel compared to untreated metal.
The Pre-Galvanising Process
Pre-galvanising, also known as ‘in-line,’ ‘continuous,’ or ‘mill’ galvanising, involves galvanising steel products using an automated process before they are cut to size and processed. Brands such as Duragal, Allgal, and Supagal employ this method. In pre-galvanising, steel components are immersed in a molten zinc bath, and excess zinc is removed through mechanical wiping, air knives, or steam, resulting in a relatively thin zinc coating.
The Hot-Dip Galvanising (HDG) Process
Hot-dip galvanising (HDG) involves immersing the fully fabricated steel product into a molten zinc bath. The steel is lowered at an angle, allowing air to escape and ensuring the zinc flows over and through the entire piece. During this process, the iron in the steel reacts with the zinc, forming zinc-iron layers topped with pure zinc. This reaction creates a robust bond between the steel and zinc, resulting in a thicker and more durable coating than pre-galvanising.
Key Differences Between Pre-Galvanised and Hot-Dip Galvanised Steel
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Coating Thickness: Pre-galvanised steel typically has a coating thickness of about 20μm for sheets and 20-30μm for tubes and wires. HDG coatings are significantly thicker, with minimum average requirements ranging from 45-85μm.
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Coating Continuity: HDG provides a continuous coating over the entire steel structure, while pre-galvanised steel may have uncoated areas at the cut edges.
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Coating Bond: Both HDG and pre-galvanised coatings form strong metallurgical bonds with the base steel.
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Coating Formability: The thinner coating on pre-galvanised steel can typically withstand forming without damage, whereas HDG should not be formed post-galvanising due to the risk of damaging the thicker coating.
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Coating Appearance: Pre-galvanised coatings are generally uniform and bright, while HDG coatings can vary in appearance.
Understanding these differences is crucial for selecting the appropriate type of galvanised steel for your project. At RHS Steel Supplies, we are dedicated to providing high-quality steel products tailored to your specific requirements.
Questions and Answers:
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Q: What types of steel products do you offer?
- A: We offer a wide range of steel products including RHS, SHS, beams, angles, flat bars, round bars, channels, and sheets. We also provide galvanized and stainless steel options.
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Q: Do you provide custom steel fabrication services?
- A: Yes, we offer custom steel fabrication services including cutting, bending, welding, and powder coating to meet your specific project requirements.
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Q: What is the lead time for orders?
- A: Lead times vary depending on the product and quantity. Standard products are typically available for immediate pickup or delivery, while custom orders may take longer. Please contact us for specific lead times.
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Q: Do you offer delivery services?
- A: Yes, we provide delivery services across Sydney and surrounding areas. Delivery times and fees may vary based on the location and size of the order.
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Q: Can I get a quote for my steel requirements?
- A: Absolutely. You can request a quote by contacting us via phone, email, or through our website. Please provide details about the products and quantities you need.
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Q: What are your business hours?
- A: We are open Monday to Friday from 7:00 AM to 5:00 PM We are closed on Saturday and Sundays.
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Q: Do you sell to the public or only to businesses?
- A: We sell to both the public and businesses. Whether you are a DIY enthusiast or a professional contractor, we are here to meet your steel supply needs.
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Q: What is your return policy?
- A: We accept returns of standard stock items within 14 days of purchase, provided they are in original condition. Custom orders and cut-to-size materials are non-returnable. Please contact us for more details.
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Q: Do you offer any discounts for bulk orders?
- A: Yes, we offer competitive pricing and discounts for bulk orders. Please contact our sales team to discuss your requirements and receive a tailored quote.
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Q: How can I contact you for more information?
- A: You can contact us by phone at 02 8102 5892, email us at
This email address is being protected from spambots. You need JavaScript enabled to view it. , or visit our website and fill out the contact form. Our team is ready to assist you with any inquiries.
- A: You can contact us by phone at 02 8102 5892, email us at
These questions and answers are designed to address common customer inquiries and provide clear, helpful information.
DuraGal Vs Duragal Plus Vs Hot-Dipped Galvanized Steel
DuraGal, Duragal Plus, and hot-dipped galvanized steel are different types of coatings applied to steel to provide corrosion protection. Here's a comparison between the three:
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Coating Process:
- DuraGal: DuraGal is a trademarked name for a type of pre-galvanized steel. It involves applying a zinc coating to the steel before it is formed into its final shape. The coating is usually lighter and thinner compared to hot-dipped galvanizing.
- Duragal Plus: Duragal Plus is a proprietary coating developed by OneSteel (now known as Liberty Steel). It is a unique zinc-aluminum-magnesium (ZAM) coating applied to steel. The coating provides enhanced corrosion resistance compared to traditional galvanized coatings.
- Hot-dipped galvanized steel: In this process, the steel is immersed in a bath of molten zinc, which metallurgically bonds with the steel surface, forming a thick layer of zinc coating.
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Thickness and Appearance:
- DuraGal: The zinc coating applied in DuraGal is relatively thinner compared to hot-dipped galvanizing. It creates a smoother, shiny surface on the steel.
- Duragal Plus: The Duragal Plus coating is usually thicker than DuraGal and provides a more robust corrosion protection. It can have a matte or shiny appearance, depending on the specific product.
- Hot-dipped galvanized steel: Hot-dipped galvanizing results in a thicker zinc coating compared to both DuraGal and Duragal Plus. It forms a uniform, dull gray or matte finish on the steel surface.
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Corrosion Resistance:
- DuraGal: While DuraGal offers corrosion resistance, the thinner coating may be less effective in highly corrosive environments or over an extended period compared to hot-dipped galvanized steel or Duragal Plus.
- Duragal Plus: Duragal Plus provides enhanced corrosion resistance due to the addition of aluminum and magnesium in the coating. It offers improved protection against corrosion in various environments.
- Hot-dipped galvanized steel: Hot-dipped galvanized steel provides excellent corrosion resistance, even in harsh environments. The thick zinc coating acts as a physical barrier between the steel and the surrounding atmosphere, protecting it from rust and corrosion.
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Weldability:
- DuraGal: DuraGal steel is often preferred for welding applications because the thinner coating is easier to remove locally before welding, reducing the release of zinc fumes during the process.
- Duragal Plus: Duragal Plus can be welded, but it may require specific welding procedures and techniques due to the presence of the ZAM coating.
- Hot-dipped galvanized steel: Welding hot-dipped galvanized steel can be more challenging due to the presence of the thick zinc coating. The high heat of welding can vaporize the zinc, leading to the release of harmful fumes.
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Cost:
- DuraGal: DuraGal is generally more cost-effective compared to hot-dipped galvanized steel and Duragal Plus, as it involves a simpler coating process.
- Duragal Plus: Duragal Plus is typically priced higher than DuraGal due to its improved corrosion resistance and added alloy elements.
- Hot-dipped galvanized steel: The process of hot-dipped galvanizing tends to be more expensive compared to DuraGal and Duragal Plus due to the additional steps involved.
The choice between DuraGal, Duragal Plus, and hot-dipped galvanized steel depends on factors such as the required level of corrosion resistance, the specific application, budget considerations, and any welding requirements.
Q: What is SHS Mild Steel?
A: SHS stands for "square hollow section" and mild steel refers to low carbon steel. SHS Mild Steel is a type of steel that is characterized by its low carbon content, making it more ductile and malleable than high-carbon steels.
Q: What are the properties of SHS Mild Steel?
A: SHS Mild Steel has the following properties: low carbon content, good ductility and malleability, good weldability, good machinability, and high strength-to-weight ratio.
Q: What are the common uses of SHS Mild Steel?
A: SHS Mild Steel is commonly used in construction, industrial and domestic applications. It is used in the construction of buildings, bridges, and other structures, as well as for making pipes, tubes, and other hollow sections. It is also used for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How does SHS Mild Steel compare to other types of steel?
A: SHS Mild Steel is less strong and hard than high-carbon steels, but it is also less brittle. It is more ductile and malleable, making it easier to work with. It is also less expensive than other types of steel.
Q: How is SHS Mild Steel typically sold?
A: SHS Mild Steel is typically sold in lengths, and the sizes vary depending on the supplier. It can be cut to specific sizes as required.
Q: How is SHS Mild Steel typically used in construction?
A: SHS Mild Steel is typically used in the construction of buildings, bridges, and other structures. It is used for making pipes, tubes, and other hollow sections. It is also used for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How is SHS Mild Steel typically finished?
A: SHS Mild Steel is typically finished with paint, galvanized or a powder coating, but it can also be left as-is with no finish applied.
Q: What is Galvanized RHS Mild Steel?
A: Galvanized RHS Mild Steel is a type of steel that has undergone a process called galvanization. This process involves coating the steel with a layer of zinc to protect it from corrosion. RHS stands for "rectangular hollow section" and mild steel refers to low carbon steel.
Q: What are the benefits of using Galvanized RHS Mild Steel?
A: The main benefit of using Galvanized RHS Mild Steel is its increased resistance to corrosion. The zinc coating provides a barrier that protects the steel from rust and other forms of corrosion. It also has a long service life and low maintenance cost, as well as good ductility and malleability, good weldability, good machinability, and high strength-to-weight ratio.
Q: What are the common uses of Galvanized RHS Mild Steel?
A: Galvanized RHS Mild Steel is commonly used in construction, industrial and domestic applications where corrosion resistance is needed, such as in the construction of buildings, bridges, and other structures, and is also used for making pipes, tubes, and other hollow sections, as well as for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How does Galvanized RHS Mild Steel compare to other types of steel?
A: Galvanized RHS Mild Steel is less strong and hard than high-carbon steels, but it is also less brittle. It is more ductile and malleable, making it easier to work with. It has the added benefit of increased resistance to corrosion compared to uncoated RHS Mild Steel
Q: How is Galvanized RHS Mild Steel typically sold?
A: Galvanized RHS Mild Steel is typically sold in lengths, and the sizes vary depending on the supplier. It can be cut to specific sizes as required.
Q: How is Galvanized RHS Mild Steel typically used in construction?
A: Galvanized RHS Mild Steel is typically used in the construction of buildings, bridges, and other structures where corrosion resistance is needed. It is used for making pipes, tubes, and other hollow sections, as well as for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How is Galvanized RHS Mild Steel typically finished?
A: Galvanized RHS Mild Steel has already been finished with zinc coating, typically no further finishing is needed. But it can also be painted over, or powder coated for added protection.
Q: What is RHS Mild Steel?
A: RHS stands for "rectangular hollow section" and mild steel refers to low carbon steel. RHS Mild Steel is a type of steel that is characterized by its low carbon content, making it more ductile and malleable than high-carbon steels.
Q: What are the properties of RHS Mild Steel?
A: RHS Mild Steel has the following properties: low carbon content, good ductility and malleability, good weldability, good machinability, and high strength-to-weight ratio.
Q: What are the common uses of RHS Mild Steel?
A: RHS Mild Steel is commonly used in construction, industrial and domestic applications. It is used in the construction of buildings, bridges, and other structures, and is also used for making pipes, tubes, and other hollow sections. It is also used for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How does RHS Mild Steel compare to other types of steel?
A: RHS Mild Steel is less strong and hard than high-carbon steels, but it is also less brittle. It is more ductile and malleable, making it easier to work with. It is also less expensive than other types of steel.
Q: How is RHS Mild Steel typically sold?
A: RHS Mild Steel is typically sold in lengths, and the sizes vary depending on the supplier. It can be cut to specific sizes as required.
Q: How is RHS Mild Steel typically used in construction?
A: RHS Mild Steel is typically used in the construction of buildings, bridges, and other structures. It is used for making pipes, tubes, and other hollow sections. It is also used for making machinery and equipment, as well as for making household items such as furniture and appliances.
Q: How is RHS Mild Steel typically finished?
A: RHS Mild Steel is typically finished with paint, galvanized or a powder coating, but it can also be left as-is with no finish applied.
Contact
RHS Steel Supplies
Unit 1, 8-20 Queen Street
Revesby, NSW 2212
Ph: 02 8102 5892
Mob: 0423 340 087
rhssteelsupplies@gmail.com
Opening Hours
Monday to Friday 7am to 5pm
P & D Imports PTY LTD Trading as RHS Steel Supplies
ABN: 60645653050