Why Fiberglass?

In many industries the superior performance of fiberglass has made it a preferred manufacturing material. Fiberglass tanks are manufactured by embedding glass fibers in a cured thermosetting resin, hence the term Fiberglass Reinforced Plastic (FRP).

All fiberglass begins as individual strands of glass drawn from a furnace of molten glass. Many strands of glass are formed simultaneously and gathered into a “strand” and a surface treatment “sizing” is added to maintain fiber properties. Glass strands are designed for several applications including water retention. The mechanical strength of a fiberglass product depends upon the amount, type and arrangement of glass fiber reinforcement within the material system and increases proportionally with the amount of glass fiber reinforcement.

The second major component of fiberglass tanks is the thermosetting resin system. Thermosetting plastics are resins that undergo an irreversible reaction when cured in the presence of a catalyst. The resin system cannot be re-melted and is insoluble. The resin systems used in fiberglass can be customized to withstand the corrosive properties of the fluid in the tanks. Nationwide Tank and Pipe’s in house research and development team will help advise on the best system for your needs.

Orthothalic Resin Systems, commonly referred as a General Purpose Resin, provides basic containment properties, but does not provide long-term corrosion and weathering resistance. Most fiberglass tank manufacturers build their standard tank using Orthothalic Resin Systems.

Isothalic Resin Systems are used when a higher degree of corrosion resistance is needed. Isothalic resins have enhanced chemical resistance, tensile strength, durability, and fatigue resistance. Due to all the enhanced properties Nationwide Tank and Pipe use an Isothalic Resin System in their standard engineered tank design to provide customers with a durable, long-lasting, maintenance free tank.

Vinyl Ester Resin Systems provide the highest quality of chemical resistance in the family of thermoset resins therefore, they are commonly used in industrial chemical applications. Vinyl Ester resins eliminates virtually all moisture vapor transfer, which provides an excellent barrier for the containment of corrosive fluids. Vinyl Ester resin provides excellent alkali resistance of the epoxy and acid and oxidizing chemical resistance of the polyester. The chemical resistance is enhanced since there are relatively few ester linkages, only terminal groups. These terminal ester groups are made hydrolytically stable which allows for the increased performance in chemical resistance, tensile strength, elongation, durability, fatigues resistance and adhesive properties.

The below graphs show the results of water immersion tests on Orthothalic Resin, Isothalic Resin and Vinyl Ester Resin. The following charts show how Vinyl Ester has the least amount of moisture vapor transfer and the best stability of the resins.

Fiberglass performance has stood the test of time, abuse of the elements and proven to be an excellent material for the construction of storage tanks of all

varieties. Nationwide Tank and Pipe pride ourselves’ on our high standards and engineer all our tanks to outperform the parameters given.

Sherri FowlerVice PresidentNationwide Tank and Pipe