Motor Torque Calculator

Torque Formula:

\[ Torque\,(lb-ft) = \frac{HP \times 5252}{RPM} \]

Torque:

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1. What is Torque?

Torque is a measure of rotational force that causes an object to rotate about an axis. In motors, it represents the twisting force the motor can generate to overcome a load.

2. How Does the Calculator Work?

The calculator uses the torque formula:

\[ Torque\,(lb-ft) = \frac{HP \times 5252}{RPM} \]

Where:

\( HP \) — Horsepower (mechanical power output)
\( RPM \) — Revolutions per minute (rotational speed)
5252 — Conversion factor (derived from the relationship between HP, RPM, and torque)

Explanation: The formula shows that torque is inversely proportional to speed when power is constant. The constant 5252 comes from the fact that 1 HP equals 550 foot-pounds per second, and there are 2π radians in a revolution.

3. Importance of Torque Calculation

Details: Torque calculation is essential for motor selection, mechanical design, and ensuring proper operation of machinery. It helps determine if a motor can handle the required load at a given speed.

4. Using the Calculator

Tips: Enter horsepower (HP) and speed (RPM). Both values must be positive numbers. The calculator will compute the torque in pound-feet (lb-ft).

5. Frequently Asked Questions (FAQ)

Q1: Why is 5252 used in the formula?
A: 5252 is the RPM at which horsepower and torque (in lb-ft) are equal. It comes from the conversion between units of power and rotational motion.

Q2: What's the difference between torque and horsepower?
A: Torque is a measure of rotational force, while horsepower is a measure of power (rate of doing work). Horsepower = (Torque × RPM) / 5252.

Q3: How does torque vary with RPM?
A: For a given power, torque decreases as RPM increases. This is why high-torque applications often use gear reduction to lower RPM and increase torque.

Q4: Can I use this for electric motors?
A: Yes, this formula works for any rotating machinery where you know the horsepower and RPM, including electric motors.

Q5: What are typical torque values for motors?
A: Torque varies greatly by motor size and type. Small motors might produce 1-10 lb-ft, while large industrial motors can produce thousands of lb-ft.