Reciprocating Pump - Displacement and Actual Capacity

A Reciprocating Pump uses reciprocating motion to cause a fluid to be moved from one location to another.  The most common is the positive displacement type.

Capacity is limited by the pump speed and number of plungers/pistons available along with other mechanical considerations such as the crankshaft and slider mechanism.

𝑃𝐷 − Displacement is the Volume Swept by all Pistons or Plungers per Unit of Time [gpm]

𝐴 − Piston or Plunger Area [in²]

𝑎 − Piston Rod Cross Sectional Area [in²] (Double Acting Piston Pump)

𝑠 − Stroke Length [in]

𝑛 − Crankshaft Rotational Speed [rpm]

𝑚 – Number of Pistons or Plungers

Actual Capacity

𝑄 − Actual Pump Capacity [gpm]

𝑛 − Number of Pistons/Plungers

𝑉𝐸 − Volumetric Efficiency (Fraction)

Input Parameters

1. To create a new case, click the “Add Case” button
2. Select the Pump Specific Speed application from the Pipeline Pumps module.
3. Enter Case Name, Location, Date and any necessary notes.
4. Fill out all required fields.
5. Make sure the values you are inputting are in the correct units.
6. Click the CALCULATE button

• Piston/Plunger Diameter [in]
• Stroke Length [in]
• Rotational Speed [rpm]
• Number of Pistons/Plungers
• Volumetric Efficiency (Fraction)

Outputs/Reports

1. View the results.
2. If an input parameter needs to be edited be sure to hit the CALCULATE button after the change.
3. To SAVE, fill out all required case details then click the SAVE button.
4. To rename an existing file, click the SAVE As button. Provide all case info then click SAVE.
5. To generate a REPORT, click the REPORT button.
6. The user may export the Case/Report by clicking the Export to Excel/PowerPoint icon.
7. To delete a case, click the DELETE icon near the top of the widget.

• Pump Displacement/Theoretical Capacity [gpm]
• Pump Actual Capacity [gpm]

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