What device controls the rate of flow of a fluid?

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Controlling the rate of flow means adjusting how open the passage is so the fluid moves at the desired speed. A flow-control valve is built specifically to throttle and regulate flow, allowing precise adjustments to the opening and thus the flow rate to meet process needs. This is different from other valves: a check valve prevents backward flow and isn’t used to regulate rate; a gate valve is mainly for on/off isolation and, when fully open, offers little ability toFine-tune flow; a ball valve is great for quick on/off actions and basic throttling but isn’t the go-to choice for precise, stable flow control. So the device best suited to controlling flow rate is the flow-control valve.