Performance Parameters Of FMC Pumps

Mainly flow rate and head, in addition to shaft power, speed and required NPSH. Flow rate refers to the amount of liquid output through the FMC pump outlet per unit time, generally using volume flow rate; head is the energy increment of transporting liquid from the FMC pump inlet to the outlet per unit weight. For positive displacement FMC pumps, the energy increment is mainly reflected in the increase in pressure energy, so it is usually expressed in terms of pressure increment instead of head. The efficiency of FMC pumps is not an independent performance parameter. It can be calculated by formulas based on other performance parameters such as flow rate, head and shaft power. Conversely, if flow rate, head and efficiency are known, shaft power can also be calculated.
There is a certain interdependent change relationship between the various performance parameters of FMC pumps. The parameter values ​​can be measured and calculated by testing the FMC pumps, and then drawn into curves to represent them. These curves are called characteristic curves of FMC pumps. Each FMC pump has a specific characteristic curve provided by the FMC pump manufacturer. Usually, the recommended performance range is also indicated on the characteristic curve given by the factory, which is called the working range of the FMC pump.
The actual working point of the FMC pump is determined by the intersection of the FMC pump curve and the FMC pump device characteristic curve. When selecting and using an FMC pump, the working point of the FMC pump should fall within the working range to ensure economical and safe operation. In addition, when the same FMC pump conveys liquids with different viscosities, its characteristic curve will also change. Usually, the characteristic curves given by the FMC pump manufacturer mostly refer to the characteristic curves when conveying clean cold water. For a dynamic FMC pump, as the viscosity of the liquid increases, the head and efficiency decrease, and the shaft power increases. Therefore, in industry, liquids with high viscosity are sometimes heated to reduce the viscosity in order to improve the conveying efficiency.