Calculate pipe friction and fitting losses in hydraulic lines with Darcy-Weisbach and the required pump pressure head.
Set the inputs and run the calculation.
Estimate pipe friction, local losses, elevation and required pump pressure.
Flow, pipe length and diameter, density, viscosity, roughness, fitting ΣK, elevation and downstream pressure.
Flow and diameter set velocity, and loss grows roughly with its square. Viscosity and roughness change friction factor; fittings and elevation can exceed straight-pipe loss in short lines.
Darcy-Weisbach Δp = λ·L/D·ρv²/2 is combined with local ΣK·ρv²/2 and hydrostatic ρgΔz. λ comes from Reynolds and Colebrook or the laminar relation.
Halving pipe diameter at constant flow greatly increases velocity and friction loss.
Sources and limits: Darcy-Weisbach/Colebrook; ISO 4413 is used as hydraulic safety context. Add valve curves and supplier loss data.
Estimate pipe friction, local losses, elevation and required pump pressure.
Hydraulic calculations link pressure difference, effective area and flow. Pressure determines force, flow determines speed, while line losses and efficiency reduce ideal values.
Darcy-Weisbach Δp = λ·L/D·ρv²/2 is combined with local ΣK·ρv²/2 and hydrostatic ρgΔz. λ comes from Reynolds and Colebrook or the laminar relation.
Flow, pipe length and diameter, density, viscosity, roughness, fitting ΣK, elevation and downstream pressure. Flow and diameter set velocity, and loss grows roughly with its square. Viscosity and roughness change friction factor; fittings and elevation can exceed straight-pipe loss in short lines.
Enter flow, pipe length and diameter, fluid density and viscosity, pipe roughness, the sum of minor-loss coefficients ΣK, elevation difference and downstream pressure. The calculator determines Reynolds number, friction factor and total pressure loss.
Halving pipe diameter at constant flow greatly increases velocity and friction loss.
Flow and diameter set velocity, and loss grows roughly with its square. Viscosity and roughness change friction factor; fittings and elevation can exceed straight-pipe loss in short lines. The result is a pre-sizing point. Higher pressure raises cylinder force; more flow raises speed but usually also increases losses and heat.
Flow in l/min, length and diameter in millimetres or metres, density in kg/m³, viscosity in mm²/s, pressure loss in bar.
Estimating required pump pressure for a planned line system, or checking whether an existing line still delivers sufficient pressure at the consumer under increased flow.
Darcy-Weisbach/Colebrook; ISO 4413 is used as hydraulic safety context. Add valve curves and supplier loss data.
Common mistake: Don't scale a halved diameter linearly – velocity rises with the square, and friction loss even more strongly; small diameter differences have disproportionate effect. Don't forget local losses from bends, tees and valves; on short lines they can exceed straight-pipe friction loss.
At the same flow, velocity rises inversely with the square of diameter, and friction loss in turn grows with the square of velocity – small diameter reductions therefore strongly increase loss.
Reynolds number decides: below about 2,300, flow is laminar with a simple friction-factor formula; above it, flow is turbulent and uses the iteratively solved Colebrook relation.
Only if their loss coefficients are included in ΣK; for specific components, supplier curves are often more accurate than a generic ζ value.
Estimate pump pressure reserve including pipe friction, fittings, and elevation difference.
Results are preliminary engineering estimates. Component approval, safety functions, material, fatigue, installation checks and the complete system assessment remain separate.