Calculate gas flow rate

Ultra-Pure Gas Systems
85 calculations
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📝 How it works:
Calculates gas flow and volume flow under standard and operating conditions with conversion to various units

Fill in the fields below and click "Calculate".

Calculating gas flow and volume flow

The gas flow rate must be calculated precisely in high-purity gas systems, laboratory technology and the process industry. Our calculator supports:

  • Normal conditions: 0°C, 1013 mbar (Nl/min, Nm³/h)
  • Operating conditions: Real temperature and pressure
  • Unit conversion: Nl/min ↔ Nm³/h ↔ scfm ↔ sl/min
  • Gas consumption calculation: Determine costs and range
  • Flow meter design: Understanding MFC/MFM specifications

Important definitions:

  • Nl/min: Normal liters per minute (0°C, 1013 mbar)
  • Nm³/h: Standard cubic meters per hour
  • scfm: Standard cubic feet per minute (USA: 60°F, 14.7 psi)
  • slm: Standard liters per minute

Conversion of standard to operating conditions:

Q_B = Q_N × (p_N / p_B) × (T_B / T_N)

Where: Q = volume flow, p = pressure (absolute!), T = temperature (Kelvin)

Example: 100 Nl/min nitrogen at 5 bar overpressure (6 bar absolute) and 25°C: Q_B = 100 × (1.013/6) × (298/273) = 18.4 l/min operating volume. Important for pipe dimensioning and pressure loss calculation!

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