Wafer Butterfly Valves

butterfly valves
A valve consisting of a disk rotating on an axis across the diameter of a pipe to regulate the flow, as in the throttles of many engines
(butterfly valve) a valve in a carburetor that consists of a disc that turns and acts as a throttle
(BUTTERFLY VALVE) A valve with a circular body and a rotary motion disk closure member which is pivotally supported by its stem. Butterfly valves come in various styles including eccentric and high-performance valves.
A valve consisting of a pair of semicircular plates that are attached to a spindle across a pipe and hinged to allow flow only one way
A butterfly valve is a valve which can be used for isolating or regulating flow. The closing mechanism takes the form of a disk. Operation is similar to that of a ball valve, which allows for quick shut off.

wafer
Fasten or seal (a letter, document, etc.) with a wafer
thin disk of unleavened bread used in a religious service (especially in the celebration of the Eucharist)
a small thin crisp cake or cookie
a small adhesive disk of paste; used to seal letters