1. What is a Hydraulic Motor Flow Calculator?

Definition: This calculator determines the required flow rate (in gallons per minute) for a hydraulic motor based on its RPM and displacement.

Purpose: It helps hydraulic system designers and technicians properly size pumps and select appropriate hydraulic motors for applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula calculates how much fluid flow is needed to achieve a specific motor speed given the motor's displacement.

3. Importance of Flow Rate Calculation

Details: Proper flow rate calculation ensures the hydraulic motor receives adequate fluid to operate at the desired speed without cavitation or excessive pressure drops.

4. Using the Calculator

Tips: Enter the motor RPM and displacement (found in motor specifications). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 231 used?
A: 231 cubic inches equals 1 US gallon, which converts the result from cubic inches per minute to gallons per minute.

Q2: What if I know the flow rate and need to find RPM?
A: Rearrange the formula: RPM = (Q × 231) / D_m

Q3: Does this account for motor efficiency?
A: No, this is theoretical flow. Actual flow needed may be higher due to volumetric efficiency losses.

Q4: What's a typical displacement for hydraulic motors?
A: Displacement varies widely from <1 in³/rev for small motors to >100 in³/rev for large industrial motors.

Q5: How does pressure affect this calculation?
A: Pressure doesn't directly affect the flow calculation but determines the power requirement and pump selection.