The reciprocating movement of the displacer, within the sort of a plunger or a diaphragm, which alternately increases and reduces the working space. so as to stop the return flow of the conveyed medium, the working space has got to be closed by two valves.
During the backward movement of the displacer, the working space increases and a vacuum is made relative to the pressure ahead of the automated suction valve. thanks to this pressure difference, the suction valve opens and therefore the conveyed fluid is sucked into the working space. Once the displacer reaches its rear dead-center position, the suction stroke ends. The suction valve closes by its own weight or by a further spring load. During the forward movement of the displacer, the working space decreases. As a result, the pressure increases. When the pressure increases to slightly above the discharge pressure, the automated discharge valve opens and therefore the fluid volume is now discharged from the working space. within the front dead-center position, the pressure valve closes. Then the subsequent stroke cycle begins.
In most reciprocating positive displacement pump designs, the flow depends only minimally on the discharge pressure. This entails a rigid pressure characterisic function. Furthermore, the flow features a linear dependency on the stroke length and stroke frequency. Reciprocating positive displacement pumps are therefore suited to the conveyance and precise metering of fluids across a good pressure and flow range.
Reciprocating Metering Pump

Minimax Pumps Pvt. Ltd.