Plan pumping loads with reliable construction calculations. Enter duty point, losses, density, and efficiency easily. Review results, graphs, exports, and guidance for site decisions.
| Scenario | Flow | Total Head | Density | Pump Eff. | Motor Eff. | Estimated Motor Input |
|---|---|---|---|---|---|---|
| Site Dewatering | 120 m3/h | 22 m | 1000 kg/m³ | 70% | 90% | 11.42 kW |
| Concrete Water Supply | 180 m3/h | 39 m | 1000 kg/m³ | 72% | 92% | 23.11 kW |
| Slurry Transfer | 95 m3/h | 31 m | 1150 kg/m³ | 63% | 89% | 14.23 kW |
| Temporary Fire Water | 250 m3/h | 48 m | 1000 kg/m³ | 76% | 93% | 46.52 kW |
Total Dynamic Head = static suction head + static discharge head + pipe friction loss + minor losses + required pressure head.
Hydraulic Power = ρ × g × Q × H ÷ 1000
Shaft Power = hydraulic power ÷ pump efficiency
Motor Input Power = shaft power ÷ motor efficiency
Recommended Motor Size = motor input power × safety factor
Where ρ is fluid density in kg/m³, g is 9.80665 m/s², Q is flow in m³/s, and H is total dynamic head in meters.
Construction projects rely on pumps for dewatering, water transfer, slurry movement, dust suppression, curing support, and temporary utility service. Choosing the right motor size is important because undersized equipment can stall under load, while oversized equipment can waste energy and increase project cost.
Pump power depends on four main drivers: flow rate, total dynamic head, fluid density, and overall efficiency. In practical site work, the total dynamic head is rarely just the vertical lift. It often includes suction conditions, discharge elevation, pipe friction, fittings, valves, bends, and any additional pressure needed at the delivery point.
This calculator uses a layered approach. It first estimates hydraulic power from the fluid and head requirement. It then adjusts that value for pump efficiency to determine shaft demand. Next, it adjusts for motor efficiency to estimate electrical input. Finally, it applies a safety factor to help with motor selection and real operating conditions.
The daily and monthly energy outputs help estimators, project engineers, and site managers compare operating scenarios. That makes the tool useful during planning, procurement, and field verification. When you compare several duty points, you can see how higher losses or lower efficiency increase electrical demand and long-run cost.
Pump power is the energy rate needed to move fluid at a selected flow and head. It can be shown as hydraulic, shaft, or motor input power.
Total dynamic head combines lift, discharge elevation, friction losses, minor losses, and pressure demand. It gives a more realistic site requirement than static height alone.
Yes. Ignoring friction losses can make the power estimate too low. Long runs, rough pipe, fittings, and valves all increase the true pumping requirement.
The pump loses energy hydraulically, and the motor loses energy electrically. Separating them shows the difference between fluid power demand and electrical input demand.
Many projects use a modest margin above calculated motor input. The exact factor depends on duty variation, startup conditions, future allowance, and procurement standards.
Yes, but enter a realistic density and efficiency. Slurry systems often need more careful review because viscosity, wear, and solids can reduce performance.
No. It estimates pump power from the inputs you provide. Pipe sizing, NPSH review, and detailed pump selection should be checked separately.
Operating cost helps compare options during planning. A more efficient duty point may reduce energy use and total project cost over long running periods.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.