Pump Selections
Determining Total Dynamic Head Height
The total dynamic head of a water system must be considered when determining the size of pumping equipment to be installed. It determines the various head losses that the pump must overcome.
Total dynamic head = elevation head + friction head loss + pressure head.
A. Elevation head – is the vertical distance which the water must be pumped. In other words the depth of the borehole
B. Friction head loss is the loss of pressure due to the flow of water through pipe and fittings. Determine diameter, length, and type of pipe material through which the water flows from the borehole. Friction loss can be overcome by using a larger pipe size or changing piping materials.
C. Pressure head – is the maximum operating pressure of the water system converted from pressure (bar) to meter of head. If you need 3bar pressure for irrigation, then simply add 30m to cover pressure head.
Pump Curve for 4SD2 Series Pumps
PUMP SELECTION USING A PUMP CURVE
In order to determine if the proposed borehole pump is properly sized, it is necessary to refer to the pump manufacturer’s performance curve or chart. The total dynamic head and desired pump capacity are applied to the pump curve to determine proper pump selection based on required electrical power input and optimum efficiency.
To determine proper pump size, locate the point on the pump curve where the pump capacity and total dynamic head intersect and select the pump which will provide the required capacity of water under the particular head conditions. If the point of intersection falls above the curve line, select the next highest pump size.
