"training a belt", c'est s'assurer qu'elle reste centrée sur les poulies/cylindres sur lesquelles elle tourne, pour éviter qu'elle ne soit en contact avec les bords, et ne s'use rapidement.

"Tracking/Training the Belt Procedures

Training or tracking the belt on your radial stacker or conveyor system is a process of adjusting idlers, pulleys and loading conditions in a manner which will correct any tendency of the belt to run other than centrally. The basic rule which must be kept in mind when tracking a conveyor belt is simple, “THE BELT MOVES TOWARD THAT END OF THE ROLL/IDLER IT CONTACTS FIRST.” You can demonstrate this for yourself by laying a small dowel rod or a round pencil on a flat surface in a skewed orientation. Then lay a book across the dowel rod and gently push push/roll it in a line directly away from you. The book will tend to shift to the left or right depending upon which end of that dowel rod the moving book contacts first."
http://www.radialstackers.com/store.asp?pid=30115

"The purpose of this information is to give you a basic understanding of the procedures for training problem conveyors, and the influence of conveyor components on conveyor belt tracking. You will find that most problem conveyors have simple tracking solutions.

Click on each picture to view a larger, more detailed image.
1 Belt Training Step 1 | D. E. Shipp Belting Company

Conveyor troughing idlers are offered in a wide variety of styles. Troughing angles include 20°, 35°, & 45°. The stands are primarily two (2) types and vary with each manufacturer.

"Straight" (over 90°) This stand has no tilt, and is designed for the conveyor belts to run in both directions. It has no real assist in belt tracking.
"Tilted" (2°) In the direction of belt travel. Conveyor belts are to run in this direction only. The 2° tilt offers good results in conveyor belt tracking.

2 Belt Training Step 2 | D. E. Shipp Belting Company

Straight stands can be tilted 2° forward by placing a 1/8" thick washer under the back side of idler stand indicated by arrows. Remember, this conveyor only runs in one direction.

Many times on reversing conveyors, the belt runs great in one direction, only to run off when reversed. Question? What are you using? If you are using tilted stands, they are good for one direction only.

On reversing conveyors where tilted stands are already in service and giving problems, you can neutralize the tilt by placing a 1/8" thick washer under the front side of the idler stand opposite the side indicated by arrows. Now with the tilted stands neutralized, you can run your conveyor belt either direction."
http://www.shippbelting.com/BeltTraining.aspx

"Training of Conveyor Belt

1. For a conveyor belt to run straight, it is essential that idlers, pulleys, and loading conditions are properly adjusted to correct any tendency of the belt to run off center.

2. The empty belt should trough well and contact the horizontal roll of all troughing idlers; for the belt to run true, all pulleys and idlers must be at right angles to the conveyor center line.

3. The empty belt should be run only for as long as necessary to observe alignment and training and to make the proper adjustments for the belt to run true."
http://www.conveyorandrubber.com/.../Training of Conveyor Be...