Industrial Automation & Control challenge
Control loops, interlocks, fail-safe design and functional safety.
Industrial Equipment · Professional Microtool
Pump Power Calculator
Total dynamic head · Friction · Shaft power
Work out total dynamic head and shaft power for a pumped line: static lift plus friction from Darcy-Weisbach, with the friction factor taken from the flow regime rather than assumed.
Start from an example: 100 m³/h through 250 m of DN150 steel, 25 m lift →
Full output
- —Total dynamic head
- —Friction head
- —Static share of head
- —Velocity
- —Reynolds number
- —Friction factor
- —Hydraulic power
- —Shaft power
- —Total dynamic head
Shaft power against flow rate
This is the curve the linear tools do not have. Static head costs the same at any flow, but friction grows with roughly the square of velocity, so power bends upward — and a line sized for today's duty gets expensive quickly when the flow goes up.
Keep it
Both carry the figures you entered, in the part of the address that is never sent to a server. Share only where that is appropriate. To keep a copy for a project file, print the page — it lays itself out as a document.
Need a model of the actual system, not a single pipe?
We can extend this to the real network — fittings, control valves, parallel pumps and duty variation — and connect it to operating data so the duty point is measured rather than assumed.
Calculation basis 6 steps · view the method →
Velocity = flow ÷ cross-sectional area—Reynolds number = velocity × diameter ÷ kinematic viscosity—Friction factor from Swamee-Jain (or 64/Re when laminar)—Friction head = f × (length ÷ diameter) × velocity² ÷ 2g—Total dynamic head = static head + friction head—Shaft power = density × g × flow × head ÷ efficiency—
Assumptions & limitations Screening estimate for preliminary sizing and system review · 7 assumptions →
This is a screening calculation for a single pipe carrying a Newtonian liquid in steady flow. It excludes fittings, valves and entry losses unless you add their equivalent length, and it does not model NPSH, cavitation, suction conditions, viscosity correction for the pump itself, or the pump's own curve. Select equipment against the manufacturer's curve and a proper hydraulic study, not against this figure.
- Steady, single-phase, incompressible Newtonian flow in one pipe of constant bore.
- Fittings, valves, strainers and entry and exit losses are excluded unless added as equivalent length.
- The Swamee-Jain approximation is used for the friction factor; it sits within about 1% of Colebrook-White over the usual turbulent range.
- Below Reynolds 2300 the laminar value 64/Re is used, and the transition region between 2300 and 4000 is not modelled honestly by either.
- Suction conditions, NPSH available and cavitation are not considered.
- Pump efficiency is taken as a fixed figure, though it varies across the curve; motor, drive and coupling losses are excluded.
- Standard gravity of 9.80665 m/s² is used.
Worked examples
- 100 m³/h through 250 m of DN150 steel, 25 m lift
Open with these figures → - A slow line: 10 m³/h through the same pipe
Open with these figures → - Laminar case: heavy oil at 400 cSt
Open with these figures →
About this tool
Head is the part of pump selection that gets guessed most often, usually by adding a round number to the static lift. This tool separates the two: what the elevation actually costs, and what the pipe adds on top — which is the part that grows with the square of flow and turns a comfortable duty point into a wrong pump. Written for process, utilities and facilities engineers doing preliminary sizing.
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