Insulated Storage Tank Linings Need Regular Inspection and Maintenance
API 653 standards for insulated tank repairs and inspections have been in place since the 1990s after storage tank failures may have contributed to environmental damage. These standards have made many storage tanks and tank linings safer and more efficient, but keeping up with API 653 standards can make repairs and inspections much more expensive. There is obviously a good reason for these standards, and ignoring them to save time and money is far more disastrous. If you have a facility that relies on insulated storage tanks, here are some of the best practices if you want to keep them in good condition and up to the proper standards.
Tank Repairs and Corrosion Under Insulation
One of the biggest problems you will face is when moisture forms underneath the insulation in your tank liners. It is known as corrosion under insulation or CUI, and it is sadly very easy to miss. There are even cases when professionals who perform routine inspections and tank repairs miss significant CUI on a five or ten-year out-of-service tank inspection since the corrosion was underneath the insulation that was meant to protect the tank itself.
Once the corrosion has taken hold in the storage tank, the only thing that can be done is to repair the tank and the lining. One long-term solution that has worked in the past is to apply epoxy coatings and FRP wraps to the corroded areas. Another solution is to add support panels that keep the insulation in place and prevent it from sagging, something that can contribute to corrosion. These support panels need a strong foundation, which can make them less cost-effective than an FRP wrap or an epoxy coating.
Preventing Moisture Damage for Tank Linings
Of course, the best way to avoid corrosion in a storage tank is to eliminate the source of corrosion altogether. Corrosion forms when water leaks underneath the tank’s insulation. This is generally done by making it easier to inspect the insulation by exposing the corner weld where the tank shell meets the floor. This raises the insulation and both protects it from moisture damage and makes it easier to inspect.
It is recommended that any storage tanks that are in use or are expected to be used be inspected once a month. Even if inspections might not prevent CUI or other types of damage to a tank or tank lining, it will make it that much easier to catch these issues so they can be repaired. It may take some time to get some tanks up to API 653 standard, but it is something that is necessary for any facility that relies on insulated storage tanks.
Bay Area Tank Lining Inspection and Repairs
Picon FRP is a Bay Area based fabrication, maintenance, and inspection company providing FRP tank repairs, FRP tank fabrication, tank inspection, and more to facilities in California and Nevada. If you have aging infrastructre that needs inspection, repairs, coating or lining, we can help. Give us a call at (510) 232-0065 or contact us online.