Gas line dimensioning

Ultra-Pure Gas Systems
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📝 How it works:
Calculates required nominal pipe diameter based on volume flow and max. desired gas velocity

Fill in the fields below and click "Calculate".

Pipe dimensioning for gas pipes

Special dimensioning for gas installations taking into account low densities. Our calculator determines:

  • Required nominal pipe diameter: DN according to DIN ISO 6708
  • Gas velocity: Keep within the optimum range
  • Compressibility: Take real gas behavior into account
  • Cost optimization: Line cross-section vs. pressure loss
  • Safety aspects: erosion and noise

Typical gas velocities:

  • Low pressure gas (<100 mbar): 1-5 m/s
  • Medium-pressure gas (0.1-5 bar): 10-20 m/s
  • High-pressure gas (>5 bar): 15-30 m/s
  • Pure gases (laboratory): 5-12 m/s (particle avoidance)

Special features for gases:

  • Much lower density than liquids (factor 1000)
  • Compressibility must be taken into account (ideal gas law)
  • Temperature dependence is more pronounced
  • Moisture can condense (pressure dew point!)

Example: 500 Nm³/h nitrogen at 6 bar, 20°C, max. 15 m/s speed. Operating volume: approx. 90 m³/h = 0.025 m³/s. Required cross-section: 0.00167 m², diameter: 46 mm. Select DN 50 pipe. With DN 40, speed would be 19.9 m/s - too fast!

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