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RPM Pulley Size Calculator by Tons of Concrete

RPM Formula:

\[ RPM2 = RPM1 \times \left( \frac{D1}{D2} \right) \]

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1. What is an RPM Pulley Size Calculator?

Definition: This calculator determines the output RPM (revolutions per minute) based on input RPM and the diameters of drive and driven pulleys.

Purpose: It helps mechanical engineers, technicians, and DIY enthusiasts calculate speed ratios in belt-driven systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ RPM2 = RPM1 \times \left( \frac{D1}{D2} \right) \]

Where:

Explanation: The speed ratio is inversely proportional to the pulley diameter ratio. A larger driven pulley will rotate slower than the drive pulley.

3. Importance of RPM Calculation

Details: Proper RPM calculation ensures optimal machine performance, prevents equipment damage, and helps achieve desired operational speeds.

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: What if I know the RPM2 and need to find D1 or D2?
A: Rearrange the formula: \( D1 = \frac{RPM2 \times D2}{RPM1} \) or \( D2 = \frac{RPM1 \times D1}{RPM2} \).

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

Q3: Can I use this for gear systems?
A: Similar principles apply, but use number of teeth instead of diameters for gears.

Q4: What's a typical RPM range for industrial applications?
A: Common ranges are 500-3600 RPM, but always check manufacturer specifications.

Q5: How does pulley ratio affect torque?
A: Torque increases proportionally as speed decreases (and vice versa), maintaining constant power.

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