1. What is Hydraulic Motor Speed Calculation?

Definition: This calculator determines the rotational speed (RPM) of a hydraulic motor based on flow rate and motor displacement.

Purpose: It helps hydraulic system designers and technicians properly size motors and predict performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula converts flow rate to cubic inches per minute, then divides by displacement to determine revolutions per minute.

3. Importance of Hydraulic Motor Speed Calculation

Details: Accurate RPM calculation ensures proper system performance, prevents motor overspeeding, and helps match motor speed to application requirements.

4. Using the Calculator

Tips: Enter the hydraulic flow rate in gpm and motor displacement in in³/rev. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is 231 used in the formula?
A: 231 is the conversion factor between gallons and cubic inches (1 gallon = 231 cubic inches).

Q2: What's a typical displacement for hydraulic motors?
A: Displacement varies widely from 0.1 in³/rev for small motors to over 20 in³/rev for large industrial motors.

Q3: Does this account for motor efficiency?
A: No, this is theoretical speed. Actual speed will be slightly lower due to volumetric efficiency losses.

Q4: How do I find my motor's displacement?
A: Check motor specifications or nameplate, or measure oil volume per revolution when manually rotating the motor.

Q5: What if my motor speed is too high?
A: Reduce flow rate, increase motor displacement, or add a speed reducer to protect the motor.