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Pipe Sizing Calculator

Determine the internal diameter of a pipe according to standard API 14E sizing criteria

Pipe Sizing Calculator - API 14E

Pipe Sizing Calculator
(API 14E)

Results

Flow Velocity
Pressure Drop
Reynolds Number
Friction Factor

Main recommendations for designing a piping system

Pipe Flow Animation
Ø

The API Recommend Practice 14E (RP14E) – Recommended Practice for Design and Installation of Offshore Production Platform Piping Systems – provides guideline to the design and installation of new piping systems.

The main recommendations for sizing a piping system are: 

Sizing Criteria

Both the flow velocity and pressure drop should be considered

Flow Rate

Use the maximum flow rate expected during the life of the facility

Surge Factor

It is advisable to add a surge factor of 20 to 50% to normal flow rate

Equivalent Length

Equivalent length may be used to include the effect of valves and fittings

Engineering Judgement

Calculated line sizes may need to be adjusted in accordance with good engineering judgement

⚠️ Disclaimer

The results provided by this calculator are for informational purposes only and should not be considered professional engineering advice. While we strive for accuracy:

  • This tool does not replace analysis by a qualified engineer
  • Results may vary based on real-world conditions and input assumptions
  • Final design decisions remain the responsibility of qualified personnel
  • We disclaim all liability for damages arising from use of these calculations

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