Motor Gearbox Torque Calculator
Calculate output torque for motor and gearbox systems
Motor Gearbox Torque Calculator
For Industrial Motor & Gearbox Applications
Results:
Output Speed (RPM): 0.00
Output Torque (Nm): 0.00
Output Torque (lb-ft): 0.00
How to Use the Calculator
Input Motor Details
- Enter Motor Power in Kilowatts (kW).
- Input Motor Speed in Revolutions Per Minute (RPM).
- Provide the Gearbox Ratio (e.g., 10 for a 10:1 ratio).
- Enter Gearbox Efficiency as a percentage (default is 95%).
Understand Outputs
- Output Speed (RPM): The rotational speed after the gearbox.
- Output Torque (Nm): The torque produced in Newton-meters.
- Output Torque (lb-ft): The torque produced in pound-feet.
- Use the "Calculate" button to see results.
Tips for Accuracy
- Ensure all input values are positive numbers.
- A typical gearbox efficiency ranges from 90% to 98%.
- Higher gearbox ratios reduce speed but increase torque.
Motor Gearbox Torque Fundamentals
Torque
Torque is the rotational force that causes an object to rotate about an axis. In motor and gearbox systems, it's crucial for determining the system's ability to perform work.
- Measured in Newton-meters (Nm) or pound-feet (lb-ft).
- Directly proportional to power and inversely proportional to speed.
Gearbox Ratio & Efficiency
- Gearbox Ratio: Determines the speed reduction and torque multiplication. A higher ratio means lower output speed and higher output torque.
- Efficiency: Represents the power lost within the gearbox due to friction and heat. Typically expressed as a percentage.
Key Formulas:
Output Speed (RPM) = Motor Speed (RPM) / Gearbox Ratio
Output Torque (Nm) = (Motor Power (kW) × 9550 × Gearbox Efficiency) / Output Speed (RPM)
Output Torque (lb-ft) = Output Torque (Nm) × 0.737562
Calculation Formulas
Output Speed (RPM):
N_out = N_motor / Ratio
Output Torque (Nm):
T_Nm = (P_kW × 9550 × Eff) / N_out
Output Torque (lb-ft):
T_lb-ft = T_Nm × 0.737562
Example Calculation
Motor Power: 5 kW
Motor Speed: 1450 RPM
Gearbox Ratio: 20
Gearbox Efficiency: 90% (0.9)
Output Speed = 1450 RPM / 20 = 72.5 RPM
Output Torque (Nm) = (5 kW × 9550 × 0.9) / 72.5 RPM = 593.10 Nm
Output Torque (lb-ft) = 593.10 Nm × 0.737562 = 437.56 lb-ft
Output Speed = 72.50 RPM | Torque = 593.10 Nm | Torque = 437.56 lb-ft