How long do galvanized trailers last?

In this article, we will answer the following question: How long do galvanized trailers last? We will explain why galvanized trailers usually have a longer lifespan, and how to maintain and protect them against corrosion. 

How long do galvanized trailers last?

A galvanized trailer will last typically between six and eight months. The life of your hot-dip galvanized steel trailer depends on the thickness of the coating, this thickness is determined by the composition of the steel used to make your trailer. N&N trailers, for example,  are typically 70 microns galvanized.

The lifespan of your hot-dip galvanized steel trailer also depends on the humidity level of your environment, contaminants on the road as well as those which may be found in greater concentration in the air in certain industrial environments.

It is important to properly maintain your galvanized steel trailer to preserve its anti-corrosive properties.

Key factors to remember about the lifespan of your galvanized trailer:

  • The service life varies depending on the thickness of the zinc coating and the environment and road contaminants (salts and de-icers). The thickness of the zinc layer during the hot-dip galvanizing process is determined by the chemical composition of the steel and the condition of its surface.

It is therefore important during winter and after use to rinse your trailer in order to remove any salt residue.

  • In a rural environment, where automobile traffic is reduced, the low amount of corrosive emissions means that galvanizing can last over 100 years without any maintenance. 

On the other hand, in an industrial or marine environment, in the presence of corrosive elements in large quantities (chlorides, sulphides), the lifespan of a galvanized structure will vary from 50 to 100 years. The service life excludes, of course, the components of the trailer which are not made of galvanized steel and other mechanisms of the trailer.

Why does a galvanized trailer usually last longer?

Since hot-dip galvanizing is not an application, it is the thickness of the coating that will dictate the life of your trailer. The thickness of the zinc on your trailer is determined by the steel and its composition. For small trailers, the zinc coating is 3 mils; for a gooseneck, the overlap is 4 mils.

The environment and contaminants on the road, such as salt and de-icers, will affect its lifespan. It is therefore important during winter and after use to rinse your trailer in order to remove any salt residue.

More than a coating or a paint, galvanization creates a real fusion between materials: iron zinc alloys.

Thus the latter offers remarkable resistance and adhesion due to the melting and progressiveness of the layers of the zinc base steel and the creation on the surface of a stable passivating layer of zinc carbonate.

What is a galvanized trailer?

A hot-dip galvanized trailer receives the hot-dip galvanizing treatment. This process is a metallurgical bond of zinc and steel produced in a factory under controlled conditions. This process, characterized by its simplicity, produces excellent anticorrosive resistance, allowing molecular adhesion between the two metals in addition to cathodic protection.

Unlike paint, which over time is repelled by rusting steel, as long as the zinc layer is present on top of the steel it will be protected against corrosion. Also, thanks to galvanic protection, the zinc coating sacrifices itself to protect the steel to which it is bonded. This so-called “sacrificial” protection will continue as long as there is zinc in close proximity.

If the coating that has been hot-dip galvanized becomes scratched or damaged, the affected steel will be protected against corrosion by the surrounding zinc. This is due to the electrochemical nature of zinc being higher than that of steel.

Galvanizing is a very strong coating that usually has to be ground to remove. If the zinc coating is damaged in places due to snagging, it is not necessary to make repairs quickly.

Maintenance of a galvanized trailer

During the 1st year, it is important to make sure not to leave the trailer in a humid place without air circulation. Like, for example, buried in snow.

If there is the presence or appearance of white powder, no action is necessary. If white or milky deposits appear, you should brush and wash them with a vinegar-based cleaner. Rinse and pat dry.

If the coating is damaged with the presence of iron rust, the affected area can be repaired with a coating (paint) rich in zinc. To do this, you must grind with a wire brush, the damaged section only, down to the iron. Then apply two coats of paint rich in zinc. Follow the paint manufacturer’s instructions.

Can you paint over a galvanized trailer?

Yes. Even if the primary reason is aesthetics, the application of paint – respecting the standards for this purpose – will prolong the life of galvanized materials. The age of the part determines what surface preparation will be necessary before painting it for optimal protection.

Why paint? The first answer is undoubtedly “for aesthetics”! The post-galvanizing painting process is known as the duplex system.

The advantages are clear:

  • The paint provides a protective barrier for galvanized steel.
  • Galvanization offers better corrosion protection than the base steel below the paint.
  • Paint peeling is minimized thanks to the protection offered by galvanization.
  • The paint-galvanization duo offers longer surface protection than each product separately;

When to paint? The painting of galvanized steel can be done at any time, that is to say at the different stages of ageing of the steel, provided that the various required procedures are followed:

  • Immediately after galvanizing treatment
  • When the galvanized steel is at 50% of its service life
  • When the thickness of the galvanized film is ≤1mils
  • At the first sign of rust.

FAQ on How long do galvanized trailers last?

What are the yellow stains on a new galvanized trailer?

Following the immersion of the parts in the cooling bath, following the galvanizing process, yellowish stains may appear on the parts. They will disappear in no time. This reaction helps the zinc to properly initiate its passivation cycle.

Why is the coating not uniform on a galvanized trailer?

The hot-dip galvanizing process is done by immersion in molten zinc. The trailers are hooked up and soaked. When an asymmetric and complex part is submerged, it is difficult to obtain a perfectly uniform coating. It is therefore normal to see some rougher surfaces and small accumulations of zinc in closed corners.

Why does a galvanized trailer become mate in time?

As it ages, the zinc changes colour. This cycle lasts for approximately 18 months. However, the anticorrosive properties are not affected. The thickness of the coating is the only determining factor.

 How to paint a galvanized trailer?

If you want to repaint a galvanized trailer, you must first ‘remove it’, i.e. pass a special product before painting it, this product will allow the paint to hold onto the zinc, otherwise, it will not hold 2 seasons.

How to protect galvanized steel?

Galvanizing is the most durable method of protecting metal from corrosion. The metal is immersed in a zinc bath, which gives it a protective layer. If this layer is damaged, the metal underneath will start to rust.

What metal is used for galvanizing?

More than a coating or a paint, galvanization creates a real fusion between iron zinc alloys.

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