Plastic Oil Tanks
Plastic oil tanks are used in the transportation and storage of oil.
They are generally fabricated from industrial grade plastics such as FRP
(fiberglass reinforced plastic) and molded polyethylene. Plastic oil
tanks are often used in applications such as domestic central heating
systems, on trucks and trains for oil transportation, in gas stations,
and any building that uses oil to fuel their heating systems.
Plastic oil tanks can be used in either above ground or underground oil storage applications, but are most commonly used in underground. One example of an above ground storage application for plastic oil tanks is the storage of heating oil for residential purposes. An example of an underground storage tank for plastic oil tanks is for the storage of heating oil for industrial or commercial purposes as well as the storage of various fuel types such as motor oils, diesel duel, fuel oil for automotive applications. Plastic materials are a popular alternative to metals like stainless steel for manufacturing oil tanks; however, plastic oil tanks are not recommended for use in the storage of certain aggressive chemicals such as strong oxidizers, aromatics, gasoline or jet fuel.
Plastic oil tanks are made a couple of different ways, but their most common processes are injection molding and contact molding. Injection molding is utilized for plastic oil tanks fabricated from polyethylene, while contact molding is for plastic oil tanks formed from FRP. Injection molding functions by first heating plastic pellets and then injecting the molten plastic material into the cavity of a split die chamber/mold, which is then clamped shut. The plastic resin cools as water or other fluids circulate through the cooling system of the mold, extracting the heat and solidifying the tank. Contact molding, on the other hand, applies many different layers to a large round mold. They are all measured in gallons and can hold anywhere from 5 to 13,000 gallons apiece. Depending on their size and the desired wall strength, oil tanks are composed of either one or two layers. They can stand alone or be integrally bundled, which means multiple tanks are attached to one another by a system of plastic internally-coated copper piping. Every plastic oil tank, whether above ground, underground, horizontal or vertical, has vents, a content gauge, an isolation valve and an overfill alarm for safety reasons.