1. What is the Pulley RPM Equation?

The pulley RPM equation calculates the rotational speed of a driven pulley based on the motor pulley size, driven pulley size, and motor RPM. It's essential for mechanical system design and power transmission.

2. How Does the Calculator Work?

The calculator uses the pulley RPM equation:

Where:

• Motor Size — Diameter of motor pulley (inches)
• Driven Size — Diameter of driven pulley (inches)
• Motor RPM — Rotational speed of motor (rev/min)

Explanation: The equation shows that RPM is inversely proportional to pulley size - larger driven pulleys result in slower speeds, while smaller driven pulleys increase speed.

3. Importance of RPM Calculation

Details: Accurate RPM calculation is crucial for proper equipment operation, preventing damage from excessive speeds, and ensuring components operate within their designed specifications.

4. Using the Calculator

Tips: Enter all pulley sizes in inches and motor RPM in revolutions per minute. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What if I have multiple pulleys?
A: For multiple pulleys, calculate each stage sequentially, using the output RPM of one stage as the input for the next.

Q2: Does belt thickness affect the calculation?
A: For precise calculations, measure pulley diameter at the belt's pitch line (center of belt thickness).

Q3: What are typical RPM ranges?
A: Common motor RPMs are 1725, 3450, or variable. Driven RPM depends on pulley ratio.

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

Q5: How does this relate to torque?
A: As RPM increases, torque decreases proportionally (assuming constant power), following the power = torque × RPM relationship.