1. What is Torque Calculation?

Torque calculation from power and rotational speed is a fundamental engineering calculation used to determine the rotational force produced by motors, engines, and other rotating machinery. The formula converts power (kW) and speed (rpm) into torque (Nm).

2. How Does the Calculator Work?

The calculator uses the torque calculation formula:

Where:

• \( T \) — Torque (Newton-meters)
• \( P \) — Power (kilowatts)
• \( N \) — Rotational speed (revolutions per minute)
• 9550 — Conversion constant (derived from unit conversions)

Explanation: The constant 9550 comes from the conversion of units: 60 seconds/minute × 1000 watts/kilowatt divided by 2π radians/revolution.

3. Importance of Torque Calculation

Details: Accurate torque calculation is essential for mechanical design, motor selection, gearbox sizing, and ensuring proper operation of rotating equipment. It helps determine if a motor can provide sufficient torque for a given application.

4. Using the Calculator

Tips: Enter power in kilowatts (kW) and rotational speed in revolutions per minute (rpm). Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 9550 used?
A: The constant 9550 is derived from unit conversions: (60 × 1000) / (2π) ≈ 9549.3, which is rounded to 9550 for practical calculations.

Q2: Can I use horsepower instead of kilowatts?
A: Yes, but you'll need to convert horsepower to kilowatts first (1 kW = 1.341 hp) or use a different constant (5252 for hp and rpm to lb-ft).

Q3: What are typical torque values for electric motors?
A: Torque values vary greatly by motor size and type. Small motors may produce 1-10 Nm, while large industrial motors can produce thousands of Nm.

Q4: Does this formula work for all types of rotating machinery?
A: Yes, this formula applies to any rotating system where power and rotational speed are known, including engines, motors, turbines, and pumps.

Q5: How does torque relate to mechanical power?
A: Torque and rotational speed together determine mechanical power output. Power = Torque × Angular Velocity, where angular velocity is in radians per second.