Plastic butterfly valves are molded from high strength thermoplastic materials and can be fabricated into a strong one-piece design. They are an efficient and reasonably inexpensive valve option for many flow control devices and are used widely in water distribution, chemical services and ventilation applications.
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Plastic Butterfly Valves
Operators of plastic butterfly valves can control the flow of a fluid or gas by pulling a lever that opens or closes the valve. In the open position, the round disc sits perpendicular to the seal around the pipe. When the lever is pulled or rotated, however, the disc rotates around so that it fits snugly into the seal and blocks all flow. In other words, the disc has two positions, either parallel or perpendicular to the flow of water. Butterfly valve manufacturers have created plastic valves in particular for their low product cost and flexibility. Other common materials include aluminum, for its light and flexible nature, which makes it a perfect gasket, and stainless steel for its strength and corrosion resistance. Plastic butterfly valves may be cheaper, but they are not as popular as their metal counterparts, mostly because of vulnerability to chemical corrosion. A breakdown of the valve means leaks and damage, so there are companies who do not take the risk.