Needle valve

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A needle valve is a type of valve usually used in flow metering applications. It is similar in operation to a gate valve but tends to use a smaller, more precisely controllable orifice. When the handle is turned, a plunger slowly descends to block flow. The handle must be turned many times to open or close the valve; therefore, unlike a ball valve, it is impossible to tell from examining the handle position whether the valve is open or closed.

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