When selecting a deep well submersible pump, buyers often assume that the pump head should be equal to the installation depth. For example, if a pump is installed 100 meters below ground, it may seem reasonable to select a pump with a 100-meter head.
However, installation depth and pump head are two different engineering parameters. Confusing them can result in insufficient discharge pressure, excessive energy consumption, unstable flow or premature pump failure.
Installation depth refers to the vertical distance from the wellhead or ground level to the installed position of the submersible pump.
The pump is normally positioned below the dynamic water level to maintain adequate submergence during operation. Installation depth is influenced by:
A pump installed at a depth of 100 meters does not automatically require a head of 100 meters. The water surrounding the submerged pump already creates hydrostatic pressure, so the effective lifting requirement is generally calculated from the dynamic water level, rather than directly from the pump position.
Pump head represents the amount of energy the pump must add to the water to overcome elevation, pipeline resistance and required outlet pressure. It is expressed in meters of water column.
For a typical deep well system, the required total dynamic head can be estimated as:
Total Dynamic Head = Vertical Lift + Pipeline Friction Loss + Required Outlet Pressure Head
Vertical lift is normally measured from the dynamic water level to the final discharge point. If the system discharges into a pressurized pipeline, irrigation network or pressure tank, the required pressure must also be converted into meters of head.
As a practical reference, 1 bar of pressure is approximately equal to 10.2 meters of water head.
Consider a deep well water-supply project with the following conditions:
The vertical lift is:
70 m + 20 m = 90 m
The total dynamic head is:
90 m + 8 m + 5 m = 103 m
Although the pump is installed at a depth of 100 meters, its required operating head is approximately 103 meters. The final model should be selected from the manufacturer’s performance curve to ensure that the required flow is delivered near the pump’s suitable operating range.
Static water level is measured when the pump is not operating. Once pumping begins, the water level usually drops because of groundwater drawdown. This operating water level is called the dynamic water level.
Using only the static water level may underestimate the actual lift. For wells with significant drawdown, this mistake can cause reduced flow, unstable operation or failure to deliver water to the intended discharge point.
Seasonal changes should also be considered. If the groundwater level falls during dry periods, the pump must still maintain adequate submergence and provide the required head.
Before selecting a deep well submersible pump, provide the manufacturer with:
These parameters allow the manufacturer to calculate the duty point and recommend an appropriate pump model, motor power and stage configuration.
Installation depth determines where the pump is positioned, while pump head determines how much energy is required to move the water through the complete system.
For reliable selection, do not match pump head directly to well depth. Calculate total dynamic head using the dynamic water level, discharge elevation, pipeline losses and required pressure, then confirm the selected model against its performance curve.
For model selection and quotation, send us your required flow rate, dynamic water level, discharge height, pipeline information and electrical supply.
When selecting a deep well submersible pump, buyers often assume that the pump head should be equal to the installation depth. For example, if a pump is installed 100 meters below ground, it may seem reasonable to select a pump with a 100-meter head.
However, installation depth and pump head are two different engineering parameters. Confusing them can result in insufficient discharge pressure, excessive energy consumption, unstable flow or premature pump failure.
Installation depth refers to the vertical distance from the wellhead or ground level to the installed position of the submersible pump.
The pump is normally positioned below the dynamic water level to maintain adequate submergence during operation. Installation depth is influenced by:
A pump installed at a depth of 100 meters does not automatically require a head of 100 meters. The water surrounding the submerged pump already creates hydrostatic pressure, so the effective lifting requirement is generally calculated from the dynamic water level, rather than directly from the pump position.
Pump head represents the amount of energy the pump must add to the water to overcome elevation, pipeline resistance and required outlet pressure. It is expressed in meters of water column.
For a typical deep well system, the required total dynamic head can be estimated as:
Total Dynamic Head = Vertical Lift + Pipeline Friction Loss + Required Outlet Pressure Head
Vertical lift is normally measured from the dynamic water level to the final discharge point. If the system discharges into a pressurized pipeline, irrigation network or pressure tank, the required pressure must also be converted into meters of head.
As a practical reference, 1 bar of pressure is approximately equal to 10.2 meters of water head.
Consider a deep well water-supply project with the following conditions:
The vertical lift is:
70 m + 20 m = 90 m
The total dynamic head is:
90 m + 8 m + 5 m = 103 m
Although the pump is installed at a depth of 100 meters, its required operating head is approximately 103 meters. The final model should be selected from the manufacturer’s performance curve to ensure that the required flow is delivered near the pump’s suitable operating range.
Static water level is measured when the pump is not operating. Once pumping begins, the water level usually drops because of groundwater drawdown. This operating water level is called the dynamic water level.
Using only the static water level may underestimate the actual lift. For wells with significant drawdown, this mistake can cause reduced flow, unstable operation or failure to deliver water to the intended discharge point.
Seasonal changes should also be considered. If the groundwater level falls during dry periods, the pump must still maintain adequate submergence and provide the required head.
Before selecting a deep well submersible pump, provide the manufacturer with:
These parameters allow the manufacturer to calculate the duty point and recommend an appropriate pump model, motor power and stage configuration.
Installation depth determines where the pump is positioned, while pump head determines how much energy is required to move the water through the complete system.
For reliable selection, do not match pump head directly to well depth. Calculate total dynamic head using the dynamic water level, discharge elevation, pipeline losses and required pressure, then confirm the selected model against its performance curve.
For model selection and quotation, send us your required flow rate, dynamic water level, discharge height, pipeline information and electrical supply.
