Pressure drop calculator for air and gas piping
Enter flow, pipe size, length and fittings. Get velocity, pressure loss and the pressure at the other end of the line.
Your line
Pipe
Fittings and valves
Results
| Actual flow in the pipe | |
|---|---|
| Straight pipe | |
| Fittings and valves | |
| Total fitting K | |
| Reynolds number | |
| Friction factor |
Pressure drop in other units
| Pa | |
|---|---|
| kPa | |
| mbar | |
| psi | |
| inH₂O | |
| inHg |
Pressure drop at other flows
| Flow | Velocity | Pressure drop |
|---|
Calculation: Darcy-Weisbach with the Swamee-Jain friction factor, fitting losses by loss coefficients (K) and gas density from the ideal gas law at the average line pressure. Values are typical engineering estimates for planning and sizing. Real losses depend on the exact fittings, pipe condition and installation. Confirm the final design with Stratovac or your engineer.
About pressure drop in air and gas lines
What pressure drop is acceptable?
For blower and booster piping, keep the total drop small compared with the machine’s pressure rise, often under 5 to 10 %. For vacuum lines, aim for less than a few percent of the absolute pressure, because every millibar lost reduces the vacuum at the point of use.
What velocity should I design for?
Typical targets are 10 to 25 m/s for blower and compressor lines and lower, around 10 to 15 m/s, for vacuum lines. Higher velocity raises noise and pressure loss quickly.
Why does the pipe diameter matter so much?
For the same flow, pressure loss varies roughly with the fifth power of the diameter. Going from 3 in. to 4 in. pipe cuts the straight-pipe loss to roughly a quarter.
Does the calculator work for vacuum?
Yes. Enter the absolute pressure of the line, for example 500 mbar absolute, and the flow at those conditions. The gas density is low in vacuum, so the velocity is high for the same mass flow.
Send us your operating point
Give us the gas, the pressures, the flow and the duty cycle. We come back with a sized proposal.
- Emailabruens@stratovac.ca
- Phone+1 438-880-4655
- Production sitesFort Lauderdale, FL, USA · Barcelona, Spain
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