Related Resources: calculators

Length of Belt Traversing Three Pulleys

Mechanics and Machine Design
Vee-Belt and Pulley Design

Length of Belt Traversing Three Pulleys

All calculators require a Premium Membership

Preview:

Length of Belt Traversing Three Pulleys

The length L of a belt traversing three pulleys, as shown in the diagram below, and touching them on one side only, can be found by the following equation.

Referring to the diagram, R₁, R₂, and R₃ are the radii of the three pulleys; C₁₂, C₁₃, and C₂₃ are the center distances; and α1, α2, and α3 are the angles, in radians, of the triangle formed by the center distances. Then:

Where:

α₁,α₂,α₃ = Degrees
R₁, R₂, R₃ = Radius (in, mm)
C₁₂, C₁₃, C₂₃ = Length (in, mm)

Reference:

Machinerys, 30th edition