Timing Pulley Flanges
Pulley Flanges are small mechanical parts that help keep belts on pulleys because without axial restriction, timing belts can walk off a pulley. This is due to the tension-resistant cord in pulleys. Cords are wound with a s-z twist and used in pairs to cancel the walk, but because they are molded at an angle into the belt, there will almost always be a tendency to walk in one direction or another. By turning a shallow journal on the end of a custom made pulley, a flange can be staked or glued to prevent belt walk.