Introduction
Pump specific speed when running, calculates increases in unit of volume in a unit of time through a unit of head pressure. The characteristics of the suction side of the impeller determine the efficiency. : N_s = \frac{N \sqrt{Q_{bep}}}{H_1^{3/4}}
N_s = \frac{N \sqrt{Q_{bep}}}{H_1^{3/4}}
Where:
ππ β Pump Specific Speed
π»1 β Head per Stage (ft)
ππππ β Capacity at Best Efficiency Point (gpm)
π β Pump Rotational Speed (rpm)
Case Guide
Part 1: Create Case
- Select the Pump Specific Speed application from the Pump Module
- To create a new case, click the βAdd Caseβ 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
- Pump Speed (rpm)
- Capacity at the Best Efficiency Point (gpm)
- Total Head per Stage at the Best Efficiency Point (ft)
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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
- Pump Specific Speed
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References
- ASME B31.4 β 1998 Edition βPipeline Transportation Systems for Liquid Hydrocarbons and other Liquidsβ, Art. 404.1
- API 1117 β Movement of In-Service Pipelines
- API 5L, API 5LS and API 5LX β Specification of Pipe Grade
- ASTM β Various β Weld Joint Factor
- CFR Code Part 192
- MMS Regulations
- USDA-SCS Modified (Permissible Velocity of Water and Soil Erodibility)
- Pipeline Rules of Thumb Handbook