1. What is the Gear Pump GPM Formula?

The Gear Pump GPM formula calculates the flow rate in gallons per minute for a gear pump based on its displacement, rotational speed, and efficiency. This is essential for hydraulic system design and pump selection.

2. How Does the Calculator Work?

The calculator uses the Gear Pump GPM formula:

Where:

• \( Disp_g \) — Displacement in cubic inches per revolution
• \( RPM_g \) — Revolutions per minute
• \( \eta_g \) — Pump efficiency (unitless, 0 to 1)
• 231 — Conversion factor (cubic inches to gallons)

Explanation: The formula calculates the theoretical flow rate adjusted by the pump's efficiency to provide the actual flow output.

3. Importance of GPM Calculation

Details: Accurate GPM calculation is crucial for proper hydraulic system design, ensuring adequate flow for system components, and selecting appropriately sized pumps for specific applications.

4. Using the Calculator

Tips: Enter displacement in cubic inches per revolution, RPM in revolutions per minute, and efficiency as a decimal between 0 and 1. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is pump displacement?
A: Pump displacement is the volume of fluid pumped per revolution of the pump shaft, typically measured in cubic inches per revolution.

Q2: Why is efficiency important in the calculation?
A: Efficiency accounts for internal losses in the pump, providing a more accurate representation of the actual flow output compared to theoretical calculations.

Q3: What is the significance of the 231 constant?
A: 231 is the conversion factor from cubic inches to US gallons (1 gallon = 231 cubic inches).

Q4: How does RPM affect GPM output?
A: GPM output is directly proportional to RPM - doubling the RPM will double the flow output, assuming constant efficiency.

Q5: What are typical efficiency values for gear pumps?
A: Gear pump efficiencies typically range from 0.8 to 0.95 (80-95%), depending on pump design, operating conditions, and fluid properties.