FRP Linings for Storage Tanks Repairs

If you are responsible for an organization that uses storage tanks, corrosion is one of your concerns. This post takes a look at how FRP linings for storage tank repairs save companies and municipalities significant money over replacing storage tank bottoms. Above ground storage tanks are notoriously corrosive which leads to leaks. In fact the rate of corrosion at ambient temperatures in carbon steel is more than 1 mil every year. That means that your new storage tank could leak in as little as 5 years. Not only do leaks lead to costly repairs but can also lead to penalties for harming the environment.

Corrosion is accelerated when later rich in chlorides and soul be salts lay at the bottom of these storage tanks. In addition to being highly corrosive on their own these elements can result in a strong electrolyte that causes corrosion to accelerate even more. The exterior of storage tanks are also under attack from corrosion. This is especially true for places which have stray electrical currents in the ground or are close to salt water or snow removal including salt.

As above ground tanks corrode they must either be repaired using FRP linings, the bottom repaired, or the entire tank replaced. FRP linings or coatings are a much more cost-effective option for corroding storage tanks. Generally, when they are used in highly corrosive environments the thickness should be no less than 60 mils.

Installing FRP Linings

For municipalities and industrial locations using above ground storage tanks the trend has been stepping away from replacing the storage tank bottoms and instead installing FRP linings. The process of installing an FRP lining is cheaper and faster than completely replacing the tank bottom. To install an FRP tank lining the tank must be empty, dry, primed, puttied, and include a catalyzed resin with a glass mat. Lastly the system is finished with a sealcoat.

Thick FRP Lining Lifespan

When the correct FRP lining is selected and installed correctly it will act as a secondary bottom for the storage tank. It is tightly bonded and will prevent leaks caused by internal corrosion for up to 20 years. In the case that the storage tank has perforations the lining can assist in bridging these small areas and help prevent leaking. Exterior corrosion is a concern but can be avoided by even thicker coatings of FRP coatings. When the thickness is increased to 120 mils an FRP lining on the inside can prevent even advanced corrosion on the exterior of the storage tank.

FRP Lining Pros & Cons

Every system is going to have pros and cons. FRP linings are widely used as they are durable and cost effective but you should know all of the characteristics before deciding on any course of action.

FRP Lining Pros

FRP linings offer great budget savings compared to replacing the bottom of the tank.
FRP linings have great lifespan and can last longer than 30 years.
FRP lining installation is faster so you won’t experience as much downtime.
FRP linings are strong and can bridge 8” holes and over 80 psi with double laminates.

FRP Lining Cons

Preparation is key and installers must be highly trained to complete the installation correctly.
If pigmentation is used ascertaining the condition of the storage tank bottom is problematic.
Potential weakness for cyclic loading which needs further research.

Hydraulic Pressure & FRP Linings

FRP linings are designed to protect and reinforce storage tanks. They are not however designed specifically to withstand high pressure which is common in hydraulic pressure systems. In one installation FRP lining was installed and after 10 years the tank sprung a leak. It was found that the leak was caused by bottom side corrosion. While this is the area that the FRP lining was installed to protect it was found that the FRP was not at fault. In fact the two holes were both about a foot in width and the only thing that had held the tank together was the FRP lining.

What Is The Pressure Limit for FRP Linings?

Studies have shown that with average temperatures common in tanks that the FRP linings will over 37 psi of strength at a single laminate thickness. However when you double the laminate thickness the coating will withstand up to 82 psi. As the average internal tank pressure is about 20 psi it can safely be said that FRP linins are up to the job even if hydraulic pressure is present.

Phoenix Valley FRP Lining Installation

If you are searching for a company that does FRP linings in storage tanks, All Kote Lining Inc. has all your needs covered. We proudly install FRP linings in any size tank for both public works, industrial facilities, and other locations that have storage tank needs. To find out how we can save you money on repairs for your storage tanks with FRP linings, please call