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SERVICE TIP Conveyor
Belting "Tracking" or training is defined as the procedure required to make the conveyor belt run "true" when empty and also when fully loaded. Tracking the belt is a process of adjusting idlers, pulleys, and loading conditions in a manner that will correct any tendencies of the belt to run other than true. A normal sequence of training is to start with the return run working toward the tail pulley and then follow with the top run in the direction of belt travel. Start with the belt empty. After tracking is complete, run the belt with a full load and recheck tracking. Tracking adjustment is done while the belt is running and should be spread over some length of the conveyor preceding the region of trouble. The adjustment may not be immediately apparent, so permit the belt to run for several minutes and at least three full belt revolutions after each idler adjustment to determine if additional tracking is required. After adjustment, if the belt has overcorrected, it should be restored by moving back the same idler, and not by shifting additional idlers or rollers. If the belt runs to one side at a particular point or points on the conveyor structure, the cause will probably be due to the alignment, or leveling of the structure, or to the idlers and pulleys immediately preceding that particular area, or a combination of these factors. If a section or sections of the belt run off at all points along the conveyor, the cause is possibly in the belt itself, in the belt not being joined squarely, or in the loading of the belt. With regard to the belt, this will be due to camber. Its condition should improve after it is operated under full load tension. It is a rare occasion when a cambered belt (less than 1/2%) needs to be replaced. These basic rules can be used to diagnose a belt running poorly. Combinations of these rules sometimes produce cases which do not appear clear-cut as to cause, but if there is a sufficient number of belt revolutions, the running pattern will become clear and the cause disclosed. In those unusual cases where a running pattern does not emerge, it is quite likely that at some point the belt is running so far off that it is fouling structure or mounting brackets, bolts, etc. This results in highly erratic performance and can be a real problem. We would suggest that in this event the full tracking procedure be employed. It is quite likely that the erratic performance will be resolved in the process. When replacing a used belt, go through the system and square and level all rollers, idlers, pulleys and bed before training a new belt. Basic/Primary
Rule of Tracking The basic and primary rule which must be kept in mind when tracking a conveyor belt is simple, "THE BELT MOVES TOWARD THAT END OF THE ROLLER/IDLER IT CONTACTS FIRST." The reader can demonstrate this for himself very simply by laying a small dowel rod or round pencil on a flat surface in a skewed orientation. If a book is now laid across the dowel rod and gently pushed by one's finger in a line directly away from the experimenter, the book will tend to shift to the left or right depending upon which end of that dowel rod the moving book contacts first. Note: Reprinted with permission of Georgia Duck and Cordage Mille, manufacturer of Georgia Duck Conveyor Belts.
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