UL 58 Steel Underground Tanks for Flammable and Combustible Liquids

EUROLAB laboratory provides testing and compliance services within the scope of UL 58 standard. The standard covers single wall and double wall bare steel underground tanks. handles leakage, buckling from outside pressure and venting. It defines the minimum thickness of the steel according to the tank diameter and length. Performance testing is not required.

The standard allows manufacturers to reduce steel thickness by up to 25%, provided the design can withstand one hour of external pressure testing. During this test, the tank is submerged to a depth equal to the manufacturer's specified burial depth or up to 5 feet, whichever is greater. The tank is not allowed to leak, collapse, burst or bend. Buckling is defined as 5% of the tank diameter during this test, or 8 inches for an 4,8-foot diameter tank.

UL 58 Standard Requirements

The requirements of the lifting handles are to be able to support a load equal to twice the empty weight of the tank for one second without permanent deformation; and ensuring that it does not leak when subjected to a leak test of 5 psi.

The standard only allows for certain types of welds, a maximum diameter of 144 inches, a minimum length-to-diameter ratio of 6:1, and a certain minimum vent size. During production, each tank should be checked for leaks. The manufacturer can aerostatically pressurize the tank to 3-5 psi and use a leak detection fluid to check for leaks, or fill the tank with water and pressurize up to 5 psi and observe.

Eurolab provides the best service to the manufacturers with its technological infrastructure in all tank standard tests.