What is a Cold Galvanizing Compound?

You need a long-term corrosion prevention solution for the project you're designing. It's critical you get a coating that's going to provide superior, time-tested protection. Perhaps you’re aware of the hot-dip galvanizing process, but the time and cost expenditure associated with outsourcing this process doesn't fit within the scope of your project.

Enter cold galvanizing compounds — a much more accessible solution for corrosion prevention. A cold galvanizing compound is a high-quality solution that is perfect for touch-ups or full-scale project application. A cold galvanizing compound has the characteristics of a paint, but it's not a paint. The biggest difference is the percentage of zinc present in the corrosion prevention coating.

"In order to be a cold galvanizing compound you need an extremely high percentage of zinc dust in the dried film - greater than 92%. That's one of the secrets as to why the performance is equivalent to hot-dip galvanizing." - Steven Collins of ZRC Worldwide

"Cold galvanizing compounds are a very high-end solution that set the gold standard of corrosion protection for iron and steel. If you want to protect a piece of steel from corrosion it's easy to use a cold galvanizing product because it's applied like a paint." - Matt Steele of ZRC Worldwide.

In order to really understand what a cold galvanizing compound is, it's beneficial to know what hot-dip galvanizing is, since both are similar corrosion-prevention solutions.

What is hot-dip galvanizing?

Hot-dip galvanizing (HDG) is the process of coating fabricated steel by immersing it in a bath of molten zinc. There are three fundamental steps in the hot-dip galvanizing process:

1. Surface Preparation
2. Galvanizing
3. Inspection

The most important aspect of hot-dip galvanization to focus on at this point is that it happens in a manufacturing plant.

How is Cold Galvanizing Different From Hot-Dip?

A cold galvanizing compound is a product that simulates the performance of hot-dip galvanizing. So what's the difference? Hot-dip galvanizing needs to be applied in a controlled setting, like a manufacturing plant. Cold galvanizing compounds can be applied, like a paint, out of a can and on-site.

You can learn more about how cold galvanizing compounds protect metal and combat rust on our How It Works page.

The Benefits of Cold Galvanizing and Zinc-Rich Coatings

Here at ZRC Worldwide, we developed the technology behind zinc-rich coating and the application as corrosion prevention solutions. In simplest terms, the benefit of cold galvanizing compounds, in the form of zinc-rich coatings, as compared to hot-dip is proximity — you can apply cold galvanized compounds on site instead of having to outsource the corrosion prevention process.

ZRC products provide an additional benefit of on-site application — yet they ship like paint cans. You achieve the same corrosion protection as hot-dip galvanizing, without the need to outsource your materials to a plant for the coating process to take place. Applying ZRC products is easy; they can be applied by aerosol, directly from the can using brushes and/or rollers, or by using readily-available spray equipment.

The percentage of zinc present in the composition of the product allows for product features and performance to reach full corrosion-resistance equivalence of the hot-dip galvanization process. This is unique in that there is no other product in the market that does this.

The outcome? A 100% zinc coating over your steel or iron surface that will prevent corrosion for years.

[This illustration shows the difference between the true galvanic protection of ZRC® and Galvilite® and other types of coatings. The difference is made possible by ZRC's high zinc content (95% by weight in the dried film) of "ultra-pure" zinc dust (ASTM D520 Type III) and proprietary, non-encapsulating binder. This unique combination provides a self-healing galvanic film that is impossible for others to match. ]

What Are Cold Galvanizing Compounds Used For?

It's easy to see the benefits of cold galvanizing compounds in the form of zinc-rich coatings. Some uses for the protections that our cold galvanizing compounds provide include:

ZRC protects steel structures, such as the railings of the Peace Bridge between Buffalo, NY and Fort Erie, Ontario. Steel is susceptible to rust when exposed to moisture and oxygen. Various parts of a bridge can be susceptible to rust due to exposure to the elements, especially in environments with high humidity or proximity to saltwater. 

Construction

You can use zinc rich coatings on structural channel frames. For example, it was used on the Bank of America Building in San Francisco, the l.D.S. Center in Minneapolis, and the Republic Bank Tower in Dallas.

Industrial Maintenance

Maintain structures and equipment both inside and outside industrial, petrochemical, and food processing plants with zinc rich coatings.

Manufacturing

ZRC has been used to prevent corrosion on the inside surfaces of water tanks like international manufacturers Leach Co. in Oshkosh, WI.

Power Plants

Protect HVAC ductwork with zinc rich coatings. They have many applications in all phases of construction as attested by their role in preventing corrosion in nuclear power plants, worldwide.

Offshore Marine Rigs

ZRC can protect above and below the water line. It is a fantastic way to prevent rust on metal in the marine environment, such as your metal fences or boat propellers. 

Transmission Towers

You can use zinc-rich coatings as original protection for structural steel or for regalvanizing support cables. ZRC prevents corrosion on the entire tower, including the tower legs, cross members, climbing facilities, guy point shackles, tension arms, platforms, and walkways, plus the nuts and bolts that hold it all together.

Water & Waste Plants

ZRC also protects steel in extremely hostile environments such as water and waste plants.

Why an Architect Should Specify ZRC on Projects

When cold galvanizing technology in the form of zinc-rich coatings was first designed back in the early 1950s by ZRC Worldwide, it was considered to be just a touch-up product for hot-dip galvanizing.

Since then, the products' high performance drove process refinement that enabled a more far-reaching scale: cold galvanizing compounds became the primary component of corrosion prevention for entire projects and were specified by product engineers in manufacturing processes as an in-plant method of galvanizing.

You know you need this kind of protection, but it’s worth pointing out that it's not enough to simply put "cold galvanizing compound"  or “corrosion preventive compound” in your spec sheet. When you are spelling out the details of your project, you want to be as clear and specific as possible. Architects should mention ZRC by name.

You can always feel good about recommending our product. We stand behind it, and you should too, because our product is superior to any competition. In fact, we have a 10-year outdoor test and numerous lab studies to prove our superior performance.

Understanding Industry Standards?

ZRC Worldwide's cold galvanizing compound meets and exceeds the requirements of ASTM A780 for hot-dip galvanizing repair. According to the product specification: "Organic Zinc-Rich coating containing 95% metallic zinc, by weight in the dried film; recognized under the Component Program of Underwriter's Laboratories, Inc. as an equivalent to hot-dip galvanizing; conforming to Federal Specification DOD-P-21035A (formally MIL-P21035A) for repair of hot-dip galvanizing and meeting the requirements of Military Specification MIL-P-26915A USAF."

"There are a lot of so-called cold galvanizing compounds in the market that don't have enough zinc in them to be electrically conductive and thus, galvanic" - Steve Collins of ZRC Worldwide.

The Association for Materials Protection and Performance (AMPP), formerly the Society for Protective Coatings, aims to regulate this. They offer a set of many standardizations, the most common of which for cold galvanized compounds is called SSPC Paint 20. You can learn more about AAMP standards, certification, and training on their website.

Myths and Misunderstandings Surrounding Cold Galvanizing Compounds

There are a lot of things that get misunderstood regarding cold galvanizing compounds.

Misconception #1: Cold galvanizing compound is a normal paint.

Another way of saying this common misconception is “Normal paint will do the same thing as cold galvanizing compound.” While they do look the same, nothing could be further from the truth. These two are not the same thing.

A cold galvanizing compound has the characteristics of a paint, but it's not a paint. The biggest difference between paint and cold galvanizing compounds exists in the percentage of zinc present in the corrosion-prevention film coating. Our unique formula provides a self-healing galvanic film that is impossible for others to match. "Ultra pure" Zinc dust (ASTM D520 Type III) is integrated with our trade-secret organic binder. This binder allows the zinc particles to remain in contact with each other so that the ZRC is anodic to the base metal, thereby imparting true galvanic action.

Misconception #2: It needs to be cold. 

The terminology "cold galvanized" does not mean that it needs to be applied in a cold environment. A normal, temperate one will do just fine. This terminology is due to the fact that ZRC products are extensively used as an alternative to hot-dip galvanizing for effective rust prevention.

Misconception #3: It is just for small areas. 

Cold galvanizing compounds can be used for the overall galvanization of entire structures and not just for touch-ups. You can paint ZRC on anything from rusty fences and gates to a commercial fishing boat to a massive transmission tower. That being said, it can be used for small spots, like boat propellers and touch-ups as well. There is no spot too large or too small to benefit from the rust protection ZRC provides.

Misconception #4: You can paint right over rust. 

Rust is a sign of corrosion, which can weaken and deteriorate metal surfaces over time. Painting over rust does not address the root problem — it just covers it up. In fact, it exacerbates the situation over time. 

Save Money in Rust Prevention With ZRC

Preventing rust is a fantastic way to save money in the long run. In The Total Cost of Corrosion: Comparing Using ZRC vs. Replacing the Metal Structure, we break down facts and figures that back up how expensive it is to let your metal assets rust away and how affordable it is to use a corrosion preventive compound instead. Download your free copy right away to learn more.