Pump performance parameters
Main flow and lift, in addition, shaft power, speed and the necessary margin of cavitation. Flow is the amount of liquid through the pump output per unit of time, generally use volumetric flow; head is the unit weight of liquid from the pump inlet to the outlet of energy increases, positive displacement pumps, energy increase mainly reflected on pressure increase, so it is usually expressed as pressure increases instead of the head. Pump efficiency is not an independent performance parameters, it can consist of performance parameters such as flow, head and shaft power calculated by formula. Conversely, a known flow, head, efficiency and can also calculate shaft power.
All performance parameters of the pump there is some interdependence between changes in relationships, you can test the pump, measured and calculated parameters, respectively, and draw curves to represent, these curves are called the characteristic curve of the pump. Each pump has a specific characteristic curve, supplied by the pump manufacturer. Usually plant characteristic curve indicates recommended performance section, known as the pump's operating range.