Butterfly valve

Butterfly valve designs use a hard seat and an O-ring or piston ring around the disk to seal. Butterfly valve may include an angularly offset and disca pressure-tight resilient seat . Butterfly valvesrange in size from small to enormous, and are well suited for large flows of gases, liquids, or slurries, offer a number of advantages when used for the proper application. They may be used in a wide variety of chemical services, they are available with small dimensions allowing for use in areas where space is limited, and they allow a high coefficient of flow. Conversely, the design of butterfly valve creates the disadvantage of not being easy to clean, and therefore should be avoided in situations that call for sterile, medical or food processing applications. Additionally, some styles may have difficulty dispensing slurries.
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