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The Benefits of Flow Coat Painting

Flow coating is the only option when it comes to transformer painting

Ever since the introduction of alternating-current, the transformer has been an essential part of a power plant substation. A transformer is an expensive- invaluable electrical device that transfers electrical energy between two or more circuits. While transformers are built to stand the test of time, the exterior paint is probably not. Whether your transformer is indoors or outdoors, it is crucial to maintain the exterior of your transformers. Preserving the surface of a transformer is similar to cleaning your car, for example. The more often you wash your car, the less you will have to worry about discoloration, scratches due to debris, or rust.

When it comes to transformers, they are the same way. Regular maintenance should be scheduled to ensure you get the most extended life out of your transformers. A transformer that has not received proper care could end up costing an arm and a leg to repaint. It might even force you to purchase a new transformer entirely. When it comes to painting, there are two options: spray painting and flow coating. Hopefully, after reading this post, it will become clear that flow coating is the only decision.

100% coverage

As you can see from the image, painting the surface area of a transformer is no easy task. There are various joints, seams, and hidden areas that are only accessible by flow coating. All of these restricted surfaces on transformers make it vital to attain 100% coverage. If there are portions of the transformer that lack a fresh coat, it will allow rust to spread in these areas which will require much more frequent maintenance. The transformer could even need to be replaced entirely as a result of the lack of professional painting.

Spray painting is one other method that is offered when it comes to painting transformers but is often only covering up the problem. Spray painting is only able to cover 50 to 75% of surface area due to these intricate protrusions and hidden areas. With spray painting also comes problems with build-ups of paint in certain areas as you cannot control the thickness of the paint. Similarly, you cannot thin out the paint to allow for it to flow down the transformer to ensure an even coat.

Flow coating is superior for various reasons, the first being its 100% coverage. Flow coating is the only method that can mimic a factory immersion finish without having to remove the transformer from the substation. With flow coating, the team can cover all of the radiator surface areas, including the backsides and all of the various restricted surfaces while remaining on-site. Flow coating also guarantees an even surface coat which leads to better protection from the elements while still allowing the transformer to dissipate heat evenly.

Little to no interruption of service

Usually, to achieve 100% coverage when painting transformers it requires dismantling the transformer, taking it to a factory, and coating each piece individually. Then the parts would be returned to the substation to reassemble. This method takes considerable amounts of time and costs a lot of money. Flow coating is a minimally invasive method of painting as it comes with little to no interruption of service. Flow coating is a huge benefit if you are unable to shut your transformer off entirely for an extended period.

Flow coating allows you to save money and limit any outage that might result from shutting your transformer down completely for painting purposes. Your business can continue while the team professionally coats the exterior, and upon finishing the transformer looks brand new.


Rust is an issue when it comes to transformers because more often than not, they are located in outdoor substations. The fact that they are outside means that they are exposed to the elements such as rain, snow, sun, and wind. Wind can not only cause damage to the transformers during extreme weather but by blowing dust particles into the transformer which can wear away paint in certain areas. Once the paint has worn away in certain areas, the constant exposure to the rain and sun can cause rust very quickly. This rust can be on exposed surfaces or surfaces that are not visible, and once the rust is present, it spreads like wildfire.

Where rust has spread on hidden surfaces, special rust remover gets applied by Flow Coating. This rust remover gets it ready for future coatings of corrosion and weather-resistant paint. The rust treatment is something that spray paint does not offer. If spray paint were to be your choice, then it would require a separate process for rust removal and treatment followed by the spray paint.

Once you have decided on Flow coating as your method of painting, the next step is understanding the multi-step process. As flow coating ensures 100% coverage and is done on-site, there is more to it than just spraying one coat of paint on your transformer.

The Process of Flow Coating

Hiring a professional painting service for flow coating protects against transformer failure and defends your company against any downtime. Ensuring that there are no gaps in your transformers exterior painting assures that no water, or wildlife, can get into the transformer, causing it to fail. Since flow coating guarantees no transformer failure stemming from cracks in the paint, your company will save money. This savings comes from not having to shut down the transformer for maintenance, or replacement, reactively. Flow coating guards your investment against the elements so that you can depend on them for the long haul.


It is essential that before beginning the painting process, thorough cleaning takes place. This cleaning is all done by the flow coating team. This cleaning must take place because if painting occurs on a dirty surface, the paint will not be able to adhere. The first step in the cleaning process is to remove any debris such as oil, dirt, chalk, or loose and flaking paint. The team will use a pressure washer and grinders to clean the exterior of the transformer to the bare metal. This washing and grinding allow for the best adhesion between the paint and the exposed surface of the transformer.

Every professional flow coating team will clean the transformer and all of its surfaces before applying the coat. Hiring a professional organization for transformer painting is crucial because it will save you money in the long run. You avoid more damage from being done to your transformer, and your transformer will have better protection from the elements.

Protecting the Transformer

Once the surface cleaning has taken place, the transformer itself needs some protection before painting can start. The team wraps the various parts of the transformer to avoid overspray. Everything external, such as signs, are removed or covered as well. Then fans are removed or covered to prevent any excess paint build-up. Heavily rusted areas must get treatment with an anti-corrosion agent. This treatment is vital as it helps seal current rust, protect against future rust, and save you money. If even just this step does not take place, it can mean rust appears in mere months forcing the transformer to get a repaint. Since we ensure a team comprised of professionals at flow coating, every measure is taken to ensure that an even coat is applied and cleanup takes place quickly.

Flow Coating

As mentioned, flow coating is the only way to ensure 100% coverage while maintaining a uniform surface. A containment system is then built around the radiator so that they can control the release of paint into the environment. This paint is not suitable for our Ozone, so we must manage as much of the release of paint particles into the environment as possible. This containment system also works as a repository to recycle paint as it flows down into the tank, off of the radiator. It also saves money as we are not wasting any of the paint. It also helps with cleanup as no paint is spilling on your substation. For flow coating to work correctly, painters thin the primer and finish coat paint out by up to fifty percent. Doing so allows the paint to flow down the radiator tubes to ensure that the layer of paint is even. Thinning the paint out also prevents any thick build-up of paint on the surface of the radiator. A thick build-up of paint on the surface of the transformer does not allow heat dissipation to occur evenly. This even layer of paint, in turn, enables your transformer to run more effectively and for much more time.

Priming for Longer Life

Once the cleaning and flow coating is complete, the team will commence priming. A quality coat of primer ensures results that last. This coat also provides a strong bond to the finish coat, which comes next. Without this step in the flow coating process, the paint would not correctly adhere to the transformer, which would mean repainting would be required.

Finishing coat

Following priming, the painters apply a poly-silicone topcoat to the transformer. This topcoat serves several purposes. First and foremost the coat adds protection against the elements which extends the life of your transformer. The reflective properties of the paint also help your transformer run at cooler operating temperatures. Last but not least, the finishing coat ensures that the exterior is left looking excellent.

Quick and Easy Cleanup

Because the flow coating team took all of the correct measures to cover and wrap all of the insulators, fans, and signs, clean up is a breeze. Protective wraps get removed and everything that was taken off, such as signs, are replaced. The transformer is left looking brand new and ready to serve your business for as long as possible.

Substation structures and transmission towers are assembled of hot-dip galvanized steel. It depends on the level of environmental exposure and the quality of the galvanizing but these need to be maintained and painted regularly. Galvanizing tends to last 15-50 years before the zinc coating is eroded so bad that corrosion of the steel on the base begins to occur. There is a way to slow down the rate at which zinc is sacrificed. Applying a protective layer of paint over the galvanizing can act as a barrier between the zinc that remains and the environment to lengthen the amount of time that the steel substrate is protected.

You can determine the life expectancy of galvanizing by the change in its appearance. As it weathers, it loses brightness and darkens due to the composition of zinc corrosion on the surface. It is a general indication that when it becomes dark grey, a lot of the zinc layer has been eroded. Doing this maintenance at the right time has significant and notable cost savings. If done correctly with the correct coatings, the service life of the structure can be doubled. Maintenance painting at a later date will extend the overall lifespan of the structure.

Aside from Flow coating, another service that we offer is high voltage insulator cleaning & coating.

Flashovers from surface contamination and wildlife contact can be limited by the application of silicone high voltage insulator coating (HVIC) on the surfaces of insulators and bushings.

The term flashover is used to describe low impedance connections in an electrical system that allows the unwanted movement of electric discharge through the air. These low impedance

connections lead to an increase in temperature and pressure in the air between electrical conductors, causing an explosion. Flashovers can cause unforeseen, unexpected power outages that result in production stoppages or breaks of customer service that can easily cost thousands or even millions of dollars.

These high voltage insulator coatings require excellent adhesion, so proper surface preparation is essential. If needed, the team cleans the insulator and bushing surfaces by gently blasting with a finely powdered limestone abrasive that does no damage to the finished surfaces. Most companies use a corn cob abrasive for cleaning; however, a limestone compound leaves no eroding residue on other substation equipment and no mess in the substation site.

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