1. What is a Hydraulic Motor Gear Calculator?

Definition: This calculator determines the gear ratio needed for hydraulic motor applications based on motor RPM, tire diameter, vehicle speed, and final drive ratio.

Purpose: It helps engineers and technicians properly size hydraulic motors and gear systems for vehicles and machinery.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( GR \) — Gear ratio (factor)
• \( RPM \) — Motor revolutions per minute
• \( TD \) — Tire diameter (inches)
• \( MPH \) — Vehicle speed (miles per hour)
• \( FD \) — Final drive ratio (factor)
• 336 — Constant for unit conversion

Explanation: The formula calculates the ratio between motor speed and wheel speed, accounting for tire size and any existing gear reduction.

3. Importance of Gear Ratio Calculation

Details: Proper gear ratio selection ensures optimal motor performance, efficiency, and prevents overloading of hydraulic systems.

4. Using the Calculator

Tips: Enter motor RPM, tire diameter in inches, desired vehicle speed in MPH, and final drive ratio (default 1.0). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the significance of the 336 constant?
A: It combines unit conversions (inches to miles, hours to minutes) and π (pi) into a single constant for simplicity.

Q2: How do I measure tire diameter accurately?
A: Measure from ground to top of tire, multiply by 2. Or check manufacturer specs for "rolling diameter."

Q3: When would I change the final drive ratio?
A: If your system already has gear reduction (like in differentials), input that ratio here.

Q4: What's a typical gear ratio range?
A: Most hydraulic applications use ratios between 5:1 to 20:1, depending on torque requirements.

Q5: Does this account for motor efficiency?
A: No, consider motor efficiency (typically 80-90%) separately when sizing the hydraulic system.