How To Calculate Peak Torque

Torque is the force required to rotate a shaft or element at a certain speed. It is a common parameter used with electric motors, which use torque to convert electrical energy to mechanical energy. Peak torque is the maximum torque that a machine or motor can produce to achieve a given number of revolutions per minute, or rpm.

Step 1

Find the horsepower of the motor or equipment. It should be displayed on the nametag on the motor or equipment; if not, refer to the manufacturer's specifications.

Step 2

Find the peak speed of the motor or engine in rpm. It should be displayed on the nametag on the motor or equipment; if not, refer to the manufacturer's specifications.

Step 3

Calculate torque (T) using the formula T = 5,252 x horsepower/rpm. The results are measured in pound-feet. For example, if you have a 40-horsepower motor designed to operate at a peak of 1,200 rpm, the formula would be T = (5,252 x 40)/1200 = 175.07 lb.-feet.