belting site top vis

Home Up Site Map Search Feedback Terms of Use




About Us








Belt Tracking

Pulley Crowns

Crowning one or several pulleys in a belt system is the most common way of tracking a belt.  For flat power transmission belts and narrow conveyor belts (200mm wide), a radius crown is used.  For wider conveyor belts, typically, a trapezoidal crown is applied.  Note: Never utilize an apex crown!

Radius Crown Specifications for Flat Belt Pulleys

A radius crown represents a great way to track a belt.  Dimensionally, it does not take a big crown height in order for the belt to track properly, and exceeding the seemingly small amounts below will actually do more harm than good!

In a system with multiple pulleys, crown the pulleys that turn the same way.


Standard Radius Crown Height  h
Pulley Face
Width Wp
Pulley Diameter  D
25-150 150-300 300-700 700-1000 1000-1500 >1500
mm mm mm mm mm mm mm
25-125 0.8 1.2 1.3 1.7 2.0 2.5
125-250 1.0 1.3 1.5 2.0 2.3 2.8
250-400 1.1 1.4 1.7 2.2 2.5 3.0
>400 1.2 1.5 2.0 2.5 3.0 3.5

convert to U.S. customary units

The min. pulley face width Wp = (belt width Wb x 1.1) + 15 mm.

The max. belt width Wb = (pulley face width Wp - 15 mm) / 1.10

Trapezoidal Crown Specifications for Conveyor Pulleys

Pulley Diameter  D Crown Height  h
mm mm
25 to 70 0.3
70 to 100 0.43
100 to 150 0.56
150 to 200 0..66
200 to 280 0.86
280 to 350 1.06
>350 1.14

convert to U.S. customary units


Note: The cylindrical part of the pulley Wc is half of the belt width Wb
Also, it is recommended for the pulley width Wp to be approximately 10 to 20% wider than the belt width Wb for the pulley crown to function properly.  For pulley widths less than 200mm, use a radius crown and refer to the flat belt pulley specifications above.


Go to the Top of this Page

Contact with questions/ comments about this web site
Copyright © 2001-2022  VIS USA, LLC