1. What is a Pulley To Pulley RPM Calculator?

Definition: This calculator determines the output RPM of a driven pulley based on the input RPM and the diameters of both pulleys.

Purpose: It helps mechanical engineers, technicians, and DIYers design and troubleshoot belt-driven systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( RPM2 \) — Output RPM (driven pulley)
• \( RPM1 \) — Input RPM (drive pulley)
• \( D1 \) — Diameter of drive pulley (inches)
• \( D2 \) — Diameter of driven pulley (inches)

Explanation: The output speed is inversely proportional to the ratio of pulley diameters - larger driven pulleys result in slower output speeds.

3. Importance of Pulley RPM Calculation

Details: Proper RPM calculation ensures equipment operates at designed speeds, prevents belt slippage, and maintains optimal power transmission.

4. Using the Calculator

Tips: Enter the input RPM, drive pulley diameter, and driven pulley diameter. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Does belt thickness affect the calculation?
A: For precise calculations, use the pulley's pitch diameter (accounting for belt thickness), but for most applications, outer diameter works fine.

Q2: What if I have multiple pulleys in the system?
A: Calculate sequentially - the output of one stage becomes the input for the next.

Q3: How does this relate to torque?
A: While RPM decreases with larger driven pulleys, torque increases proportionally (assuming no power loss).

Q4: Can I use this for metric measurements?
A: Yes, as long as both diameters use the same units (mm, cm, etc.), the ratio remains the same.

Q5: What's a typical RPM range for belt drives?
A: Most belt drives operate between 500-3000 RPM, but consult manufacturer specifications for your specific system.