2023-10-18
A metering pump is a type of positive displacement pump used to precisely control the flow rate of fluids. It operates through a controlled reciprocating motion to deliver a specific volume of liquid within a given time frame. Here's an overview of how a metering pump works:
Suction Stroke: The pump's reciprocating mechanism begins with a suction stroke. During this phase, the pump's diaphragm, piston, or other moving component retracts, creating a low-pressure area in the pump's inlet or suction side.
Inlet Valve Opens: As the pump's moving component retracts, the inlet valve opens. This allows the liquid to be drawn into the pump's chamber from the supply source, such as a tank or a pipeline. The inlet valve is typically a check valve, allowing the liquid to flow in only one direction, into the pump.
Discharge Stroke: After the suction stroke, the reciprocating mechanism starts the discharge stroke. The diaphragm, piston, or plunger moves in the opposite direction, compressing the liquid within the pump chamber.
Outlet Valve Opens: As the pump's moving component compresses the liquid, the outlet valve opens. The outlet valve is another check valve, positioned on the discharge side of the pump. It allows the liquid to exit the pump but prevents it from flowing back into the pump chamber during the discharge stroke.
Liquid Discharge: During the discharge stroke, the compressed liquid is forced out of the pump through the outlet valve and into the discharge line. The pump's flow rate is precisely controlled by the stroke length, stroke rate, and the size of the pump's chamber.
Cycle Repeats: The pump continues this reciprocating motion in a continuous cycle, alternating between suction and discharge strokes. The speed and frequency of the strokes can be adjusted to control the flow rate of the liquid accurately.
Accuracy and Adjustment: Metering pumps are designed for high accuracy and repeatability. They are often equipped with mechanisms for stroke length adjustments, stroke rate adjustments, and sometimes even sophisticated control systems to maintain precise flow rates.
Metering pumps are commonly used in various industries, such as water treatment, chemical processing, oil and gas, pharmaceuticals, and agriculture, where accurate and controlled dosing of fluids is essential for the process.