Pipe Diameter
Pipe diameter is based on flow rate (barrels/day) and velocity (ft./sec) in accordance with API recommended practices. Change in inlet pressure can cause cavitation of the pump and create occurrences outside the limits this calculation. D_i=\sqrt{\frac{0.012Q}{V}}
D_i=\sqrt{\frac{0.012Q}{V}}
Average Flow Velocity
Calculating the average liquid flow using the internal diameter the average liquid velocity ft./sec can be calculated using flowrate and diameter. Significant changes in the liquid flow due to operational changes can be a limiting factor. V=\frac{0.012Q}{D_i^2}
V=\frac{0.012Q}{D_i^2}
Where:
𝑉−Average Liquid Flow Velocity (ft/sec)
𝑄−Liquid Flow Rate (bbl/day)
𝐷𝑖−Internal Pipe Diameter (in)
Case Guide
Part 1: Create Case
- Select the Pump Station Piping application from the Pump Module
- To create a new case, click the “Add Case” button
- Enter Case Name, Location, Date and any necessary notes.
- Fill out all required Parameters.
- Make sure the values you are inputting are in the correct units.
- Click the CALCULATE button to overview results.
Input Parameters
- Liquid Flow Rate (bbl/day)
- Average Liquid Flow Velocity (ft/sec)
- Pipe Internal Diameter (in)
Pipe Diameter
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Average Flow Velocity
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Part 2: Outputs/Reports
- If you need to modify an input parameter, click the CALCULATE button after the change.
- To SAVE, fill out all required case details then click the SAVE button.
- To rename an existing file, click the SAVE As button. Provide all case info then click SAVE.
- To generate a REPORT, click the REPORT button.
- The user may export the Case/Report by clicking the Export to Excel icon.
- To delete a case, click the DELETE icon near the top of the widget.
Results
- Pipe Internal Diameter (in)
- Average Liquid Flow Velocity (ft/sec)
- Erosional Velocity (ft/sec)
- Sonic Velocity (ft/sec)
Pipe Diameter
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Average Flow Velocity
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References
- ASME B31.4 – 1998 Edition “Pipeline Transportation Systems for Liquid Hydrocarbons and other Liquids”, Art. 404.1
- API 1117 – Movement of In-Service Pipelines
- API 5L, API 5LS and API 5LX – Specification of Pipe Grade
- ASTM – Various – Weld Joint Factor
- CFR Code Part 192
- MMS Regulations
- USDA-SCS Modified (Permissible Velocity of Water and Soil Erodibility)
- Pipeline Rules of Thumb Handbook