Table Of Content
- Definition and basic information displayed on a pump curve
- Using a pump curve to select the right pump
- Reading and interpreting pump curve data
- Limitations of pump curves
Before investing in a centrifugal pump, it is essential that you understand your requirements and make sure the pump is able to meet them effectively. This is where pump curves come in. Typically, pump curves include performance curves, horsepower and the NPSH needed. VEMC is one of the leading industrial water pumps dealers in Mumbai and in this blog, we tell you all you need to know to understand pump curves.
Definition and basic information displayed on a pump curve
To put it quite simply, a pump curve is a graph that displays the flow rate, head (pressure), efficiency and operating range of a centrifugal pump. Typically, the data is plotted between the flow rate (X-axis) and the head (Y-axis). With an increase in the flow rate, the head decreases gradually.
Using a pump curve to select the right pump
A pump head signifies the difference between a pump’s inlet and outlet pressure and depends upon pipe designs and configuration. With the increase in the pressure of a centrifugal pump, there is a decrease in the discharge flow with the output dropping to zero. When there is no head to work against, maximum possible output can be achieved within the constraints of the pump design, rotation and impeller speed. The pump curve specifies the range of performance of a pump between these two points.
Performance of a pump can be modified by using a different impeller or operating the pump at varying rotational speeds. A ‘tombstone’ chart is usually used to display the possible range of performance of a particular pump. The upper line of each segment is the pump curve at a particular speed, impeller size and design.
Reading and interpreting pump curve data
Being able to read an interpret pump curve data is necessary to predict the performance of your pump in different operating conditions. Here’s how you can read a pump curve:
- Start by identifying the main components of the curve like flow rate and head.
- Get acquainted with the performance curve that represents your pump’s head at various flow rates.
- Find the duty point, that is, where the system curve intersects with the pump performance curve.
- Understand the power curve that represents the electricity consumption of the pump.
- Find out the ‘efficiency islands’, that is, zones of maximum efficiency of the pumps.
Limitations of pump curves
While pump curves are theoretically great to predict your pump performance and also select the right pump for your tasks, in real-world situations, things can be slightly different. Factors like low flow operation, bearing failures, cavitation, seal breakage etc. can significantly affect and alter your pump’s performance.
Despite these limitations, a pump curve is an extremely useful tool if you are in the pumping industry. For more on pump performance curves, feel free to get in touch with VEMC by calling on 022 43436655 or email us at marketing@vemc.co.in. We are one of the leading industrial water pumps dealers in Mumbai.