1. What is Hydraulic Pump Flow Rate?

The hydraulic pump flow rate (GPM) measures how much fluid a pump can move per minute. It's crucial for determining system performance, component sizing, and ensuring proper operation of hydraulic systems.

2. How Does the Calculator Work?

The calculator uses the fundamental hydraulic pump flow equation:

Where:

• \( Displacement \) — Pump displacement per revolution (in³/rev)
• \( RPM \) — Pump speed in revolutions per minute
• \( 231 \) — Conversion factor (231 in³ = 1 gallon)

Explanation: The equation calculates how many gallons of fluid the pump can deliver each minute based on its displacement and operating speed.

3. Importance of GPM Calculation

Details: Accurate flow rate calculation is essential for proper hydraulic system design, ensuring adequate flow for actuators, preventing cavitation, and optimizing system efficiency.

4. Using the Calculator

Tips: Enter the pump's displacement (typically found in manufacturer specifications) in cubic inches per revolution and the operating speed in RPM. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between theoretical and actual GPM?
A: Theoretical GPM is calculated as shown, while actual GPM accounts for pump efficiency (typically 85-95% for good pumps).

Q2: How does pressure affect flow rate?
A: In a fixed displacement pump, flow rate is primarily speed-dependent. Pressure affects the horsepower required but not the flow rate (assuming no significant leakage).

Q3: What if my pump specs are in cc/rev?
A: Convert cc to in³ by dividing by 16.387 (1 in³ = 16.387 cc) before using the calculator.

Q4: Why is 231 the conversion factor?
A: There are 231 cubic inches in one US liquid gallon, which converts the volume/time to gallons/minute.

Q5: How do I account for multiple pumps?
A: Calculate GPM for each pump separately and add them together for total system flow.