Flat Belt Length and Pulley Center Distance Calculation

  V and Flat Belt Design Guide Menu

The maximum center distance between pulley's should  be about 15 to 20 times the pitch diameter of the smaller pulley. The greater the spacing between pulley's will result in large differences in belt tension relative to any stretch of the belt. It is recommended that positioning devices be included within the belt tension system, to easily control and help set the belts tension. Spring loaded idler pulleys are a great system addition is the installation and operating load permit. Friction systems normally require

Friction Flat Belt Length Calculation :

Crossed Belt Friction Belt Drive

Where:

L = Length (inches)
C = Center Distance (inches)
D₁ = Pitch Diameter of Small Pulley (inches)
D2 = Pitch Diameter of Large Pulley (inches)

When calculating the length of a belt on a serrated type drive, either application equations should be divided by the serration pitch. Additionally, the belt length should be adjusted to provide a whole number of serrations.