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5.11.3 Belt Tracking Principles
Only qualified and experienced individuals should perform belt tracking procedures,
which must be performed while the conveyor is running. Verify E-stop functionality
before beginning a belt tracking procedure.
Monitor the belt during its initial startup and tracking, to ensure it does not track
completely off a pulley or rub on internal conveyor components. Damage to the belt
edge or other components can result. If possible, run the conveyor slowly at first until
initial belt stability is verified.
Along the length of the conveyor, there are several points where adjustable rollers are installed for belt
tracking. All of these adjustable rollers should be set square with the conveyor frame to start the tracking
procedure. If multiple rollers with opposing tracking tendencies are allowed to "fight" each other, unstable
tracking and accelerated belt wear can result.
1. Begin the tracking procedure with all modules in the "down" position (air supply off).
2. When correcting a belt that is running to one side, follow the belt upstream (against the belt's
running direction) to find the adjustable roller nearest to where it begins to track off.
a. In a group of rollers, all other things being equal, the first roller the belt contacts will have
the greatest tracking influence.
b. Pivotable snub rollers in the drive, tails, and tracking modules, with approximately 30° of
belt wrap, have a much greater tracking influence than the pivotable return rollers that
have minimal wrap.
c. The crowned tail pulleys should be set square so that the restoring force created by the
crown remains in the center of the conveyor. Use the tail snub roller for tracking instead.
d. To fix tracking problems at the infeed tail, track the belt before it enters the infeed tail (at
the next tracking module or at the discharge tail if the conveyor is short). The snub roller
at the infeed tail is best used to direct the belt after it exits the infeed tail on the return
span.
e. In the initial stages of tracking, do not use the adjustable center module rollers except for
those in the tracking modules. Keep them set square until the belt is fully tracked with all
modules in the "down" position.
3. Adjust the roller to steer the belt back towards center. Start by making approximately 1/16"
adjustments (1 full turn on a 3/8"-16 jack bolt). When the belt is nearly tracked, 1/32" (half turn) or
even smaller increments may be needed.
4. The roller will "aim" the belt perpendicular to the axis of rotation, in the direction of belt travel. Or,
the belt will track towards the side of the roller it touches first. See .
5. Make only small adjustments to a single roller at a time, and wait for the adjustments to take
effect before adjusting other rollers.
a. It will generally take 3 full revolutions of a belt for the effects of a tracking adjustment to
fully stabilize.
b. The most significant tracking effects are seen downstream of the roller that has been
adjusted, but there will be some effect on upstream tracking as well.
c. If larger adjustments are needed to prevent the belt tracking all the way off a pulley,
monitor that area once the belt is under control. It may be necessary to adjust the pulley
back in the other direction (reduce the magnitude of the initial adjustment) once the belt is
running stably.
d. Tracking adjustments can potentially affect the entire belt path. Particularly after a large
adjustment is made, allow the belt to stabilize and check for newly developed tracking
issues in other areas of the conveyor before proceeding.
Published November 2021
Installation and Maintenance Manual: RZPAC
Rev. B
39
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