1. What is an RPM to Flow Rate Calculator?

Definition: This calculator converts rotational speed (RPM) to flow rate (GPM) based on pump displacement.

Purpose: It helps hydraulic engineers and technicians determine the flow rate of pumps based on their rotational speed and displacement.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( RPM \) — Rotational speed (revolutions per minute)
• \( D_p \) — Pump displacement (cubic inches per revolution)
• \( 231 \) — Conversion factor (cubic inches per gallon)

Explanation: The formula calculates how much fluid a pump moves per minute based on its speed and displacement volume.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculation ensures proper system design, pump selection, and performance evaluation in hydraulic systems.

4. Using the Calculator

Tips: Enter the pump RPM and displacement (in³/rev). Both values must be > 0. The result shows flow rate in gallons per minute (GPM).

5. Frequently Asked Questions (FAQ)

Q1: Why is 231 used in the formula?
A: 231 cubic inches equals 1 US gallon, which converts the volume from cubic inches to gallons.

Q2: What's a typical displacement value?
A: Displacement varies by pump size and type. Common values range from 0.1 in³/rev for small pumps to 10+ in³/rev for large industrial pumps.

Q3: Does this account for pump efficiency?
A: No, this calculates theoretical flow. For actual flow, multiply by the pump's volumetric efficiency (typically 80-95%).

Q4: Can I use this for any pump type?
A: Yes, it works for gear, piston, and vane pumps as long as you know the displacement per revolution.

Q5: How does flow rate relate to system pressure?
A: Flow rate determines speed of actuators, while pressure determines force. They're related by power (HP = (GPM × PSI) / 1714).