Composites Today

Magazine For Composites Professionals

AOC’s material resisting corrosion from inside and out: A case study

This article is a case study published at AOC EMEA website

According to Edward Alejandro Avendaño, Production Manager for Tank Tech, the performance of Vipel® F798 high-crosslinked polyester played a major role in material selection. “The project location near the beach raised concerns about potential corrosion from the salinity of the environment,” he said. “For interior protection, the formulation is certified under the UL1316 standard for underground storage of gasoline. This gives the customer peace of mind with the security of having a safe product.”

Avendaño pointed out the benefits of Vipel® F798 formulations lower styrene content and higher elongation properties than alternative formulations: “The reduction in emissions and the characteristic odor is noticeable and appreciated by members of the production team. The formulation also gives laminates with greater hardness, which translates into better performance of the finished pieces.”

Tank Tech product performance was coupled with AOC Formulations renowned technical service. “Since the beginning of Tank Tech, we have had the support of the AOC team headed by Corrosion Product Manager, Michael Siegel, and Tech Service Manager, Cesar Carrasco, ” Avendaño said. “They offer valuable advice on such critical issues as resin working time, post-curing, and final layers.” 

Superior Design and Manufacturing

Tank Tech composite manufacturing starts by spraying formulation-impregnated chopped glass fibers onto a rotating mold to form a semi-cylindrical tank section. The spray-up stream has a high 70-to-30 formulation-to-glass ratio to ensure maximum protection against the storage medium. The sprayed composite is applied as two separate wallsections that integrally encapsulate a special three- dimensional fabric that creates an annular space.
For public safety and environmental protection, the space is part of a system that monitors the tank 24/7 for potential leakage.

After the semi-cylindrical component cures, it is demolded and integrally joined with another half- section using hand lay-up of formulation-impregnated fiber mat and woven roving. Essential to Tank Tech’s design-engineering are trapezoidal cross- section ribs that technicians integrally encapsulate into the tank’s outer wall. The trapezoidal ribs provide monolithic structural reinforcement, maintain cylindrical geometry and resist forces acting on the tank.

The vessel’s profile is completed by integrating Tank Tech-designed hemispherical domes at each end of the completed cylinder. The end domes are molded using hand-lay up of resin-impregnated fabric and woven roving.

“Any surface that can come into contact with the hydrocarbon must be able to resist corrosive attack,” Avendaño said. “As a result, the entire tank is made of Vipel® F798 resin. The material is also used to mold the access panel, reservoir, rings, and explosive containment boxes. AOC technology and support helps us manufacture in a controlled and safe manner and deliver a product with the high performance our customers deserve.”

Tank Tech is a leading manufacturer of underground and aboveground composites storage tanks that meet industry standards for flammable and combustible materials. Located in the Tocancipá Free Trade Zone of Colombia, the company is a member of the International Petroleum Equipment Institute and follows the Institute’s strict protocols for safety and performance.