Contents
What type of curve is a pump curve?
Certified pump curve It includes the actual points that were tested and specifics of the pump being supplied. A system curve identifies the pressure required to move the fluid through a system at various flow rates. This helps you to determine where the pump curve and the system curve will intersect.
What is pump system curve?
A system curve, as shown in Figure 2, is a graphical representation of the pump head that is required to move fluid through a piping system at various flow rates. The system curve helps quantify the resistance in a system due to friction and elevation change over the range of flows.
What is characteristic curve of pump?
The performance of a centrifugal pump can be shown graphically on a characteristic curve. A typical characteristic curve shows the total dynamic head, brake horsepower, efficiency, and net positive Suction head all plotted over the capacity range of the pump.
What is NPSH pump curve?
The pump curve identifies the NPSHR, not Net Positive Suction Head Available (NPSHA). NPSHA is a calculation of the head the system is able to deliver. If sufficient NPSH is not met, the pump will cavitate, affecting performance and pump life.
What is fan system curve?
• The fan curve represents the performance of a. fan. It shows the relationship between the. flow rate and pressure created by the rotation of a fan impeller.
What is characteristic curve?
A characteristic curve is a graph of the relationship between the amount of exposure given a film and it’s corresponding density after processing. The shape of the curve represents the tonal response of the film to a wide range of exposures and to one particular processing condition.
How is NPSH calculated?
NPSH (A) = (Pressure on the liquid surface) (ha) ± (suction head/lift) (friction loss) (vapour pressure) (hvp) NPSH (A) = 9.02 + 4-1.2 – 0.25 = 11.57 Mts.
How pump curves are generated?
Pump curves can be generated by reading measurements of pressure, NPSH, power, efficiency and others, while the pump is operating at different flow conditions. These results are then plotted against the flow rate to generate the pump characteristic curves.
What do you mean by a pump curve?
A pump performance curve indicates how a pump will perform in regards to pressure head and flow. A curve is defined for a specific operating speed (rpm) and a specific inlet/outlet diameter. In our example below, these curves show the performance at 1450 rpm for a 3” inlet/2” outlet.
How is the Y axis of a pump curve measured?
The final portion of the pump curve is the power curve. Once again the x-axis is measured in units of flow, but the y-axis is now measured in power units. In this case the unit of measurement is horsepower, but in the case of an application measured in metric units, power is typically measured in kilowatts.
How to read the flow curve of a centrifugal pump?
Net Positive Suction Head (NPSH) in centrifugal and positive displacement pumps For example, if you know the flow rate your application requires, you find the gallons per minute (or hour) rate along the bottom horizontal line of the curve and then draw a line up to the head/PSI you require.
What should the impeller be on a pump curve?
The curve above shows impeller trim sizes, at the right end of each curve, ranging from a minimum of 4.33″ to a maximum of 6.42″. Reducing impeller size enables you to limit the pump to specific performance requirements.