Calculate Torque From KW And RPM

Torque Formula:

\[ T = \frac{kW \times 9550}{RPM} \]

Torque (T):

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1. What is Torque Calculation?

Torque calculation from power and rotational speed is essential in mechanical engineering and motor applications. It determines the rotational force produced by an engine or motor based on its power output and speed.

2. How Does the Calculator Work?

The calculator uses the torque formula:

\[ T = \frac{kW \times 9550}{RPM} \]

Where:

\( T \) — Torque in Newton-meters (Nm)
\( kW \) — Power in kilowatts
\( RPM \) — Rotational speed in revolutions per minute
\( 9550 \) — Conversion constant (derived from unit conversions)

Explanation: The formula converts power (kW) and rotational speed (RPM) into torque, representing the twisting force available at the shaft.

3. Importance of Torque Calculation

Details: Accurate torque calculation is crucial for motor selection, gearbox design, mechanical system analysis, and ensuring proper operation of rotating machinery.

4. Using the Calculator

Tips: Enter power in kilowatts and rotational speed in RPM. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of the constant 9550?
A: The constant 9550 comes from unit conversions: 1 kW = 1000 W, 1 minute = 60 seconds, and the relationship between power, torque, and angular velocity.

Q2: Can this formula be used for electric motors and engines?
A: Yes, this formula applies to both electric motors and internal combustion engines when calculating shaft torque from power and speed.

Q3: What are typical torque values for different applications?
A: Torque values vary widely - small motors may produce 1-10 Nm, automotive engines 100-500 Nm, while industrial machinery can reach thousands of Nm.

Q4: How does torque relate to horsepower?
A: Horsepower can be converted to kW (1 hp ≈ 0.7457 kW) and then used in this formula to calculate torque.

Q5: Are there limitations to this calculation?
A: This calculation assumes constant power and speed. For variable conditions or systems with significant losses, more complex analysis may be needed.