When it comes to structural integrity, outdoor performance, and long-term durability, few components work harder, or get less recognition, than the fasteners holding it all together.
At Eurolink Fastener Supply Service, we specialize in hard-to-find and high-performance metric fasteners, including Hot Dip Galvanized (HDG) structural bolts. These fasteners offer the strength of Class 10.9 steel combined with one of the best corrosion-resistant coatings in the industry, making them the go-to solution for infrastructure and high-stress outdoor projects.
Whether you're an engineer, project manager, or distributor looking for reliable structural hardware, this guide breaks down everything you need to know about HDG metric fasteners: from how they’re made to where they’re used and how Eurolink can help you source them quickly and confidently.
Structural fasteners, such as hex bolts, nuts, and washers, are built to handle heavy loads and high-stress connections. When hot-dip galvanized, these fasteners are coated with a thick layer of zinc by immersing them in molten zinc at over 800°F. This creates a durable, corrosion-resistant layer ideal for long-term outdoor use.
Common HDG Structural Fasteners We Stock:
Eurolink stocks a wide range of these parts from M12 to M30 in a hot-dip galvanized finish, with a plain finish available upon request. MTRs (Material Test Reports) are kept on file for all structural items.
HDG fasteners are essential in outdoor and infrastructure applications, where moisture, humidity, and environmental exposure threaten uncoated steel. Compared to standard zinc-plated fasteners, hot dip galvanizing creates a coating 5–12 times thicker, offering decades of protection.
While salt spray testing (EN ISO 9227) is commonly used to test coatings, it’s not reliable for HDG. That’s because salt spray tests prevent the natural passivation layer from forming, underestimating HDG’s performance. According to industry sources, HDG coatings of 50μm can provide 20–30 years of corrosion resistance, especially in rural or moderately corrosive environments.
Some may ask, “Why not just use stainless steel?”
The answer: while stainless steel offers corrosion resistance throughout the material, it’s significantly more expensive and not as strong as Class 10.9 steel. HDG on 10.9 fasteners delivers a balance of mechanical performance, cost efficiency, and corrosion resistance, making it the preferred choice in most structural and infrastructure applications.
Eurolink’s HDG fasteners are commonly used in high-load and high-corrosion environments such as:
Any time you're bolting together structural steel in an outdoor setting, HDG is the smart choice.
One important detail with HDG fasteners is the thread fit. Because the zinc coating adds significant thickness, HDG fasteners must be specially tapped to accommodate this:
At Eurolink, we stock tZn HDG bolts to ensure seamless integration into your assemblies, especially when replacing zinc-plated fasteners or meeting tight mechanical requirements.
At Eurolink, we don’t just carry HDG bolts…we understand how, where, and why they’re used.
From the line card, here are some commonly stocked sizes (in millimeters):
View our full line card or contact our team for a complete list of in-stock items.
Hot dip galvanized structural fasteners are the workhorses behind bridges, buildings, and infrastructure around the world. With the mechanical strength of Class 10.9 steel and a corrosion-resistant coating that stands the test of time, they’re the clear choice for outdoor structural connections.
Eurolink Fastener Supply Service is your trusted source for these metric fasteners, whether you’re sourcing 100 bolts or 100,000.
Contact the Eurolink team today.