Conveyor Belt Tracking
How to track a conveyor belt has always been a key issue in running a conveying system, Bsbelt, a reliable belt expert, spares no effort to frame a belt tracking 101 guide for you.
Whether you want to learn some practical skills of tracking a belt or guide your customers in how to track and adjust a conveyor belt, this article will offer the takeaway you want.
As we all know, tracking a belt requires a good understanding of how a conveyor belt works. This article will start by introducing every single factor that may affect belt tracking, from the belt itself to the system running it.
After that, you will see practical tips for belt tracking as well as skills for belt tracking adjustment. All tips will be explained fully, and pictures will be added for your understanding if necessary.
All in all, this article is aimed to offer some conveyor belt tracking methods to help reduce unplanned downtime, extend the conveyor belt lifespan, and save money and effort on belt maintenance.
How to Eliminate Conveyor Belt Tracking Issues
The best way to completely eliminate all conveyor belt tracking problems is to prevent uneven force born by the belt.
First, you need to know why belt mistracking will happen, and the major origin is the belt bears uneven forces from different directions, whether laterally or vertically.
Once the resultant force isn’t zero, the reaction force of the idler roller or the roller to the belt produces a component force to one side, which results in the belt mistracking to one side under the action of this component force.
Possible Causes for Belt Mistracking
Though the major reason is uneven forces, which may be a result of many factors and will lead to diverse forms of belt tracking malfunctions.
Based on that fact, the next section will take an deep look at belt tracking causes and eliminate possible factors one by one. Of course, the conveyor belt tracking solutions will come alongside.
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Belts Tracking Issue Caused by The Belts
1. Bad quality of belts
A belt will bear irregular forces laterally due to the uneven density of fabric at its core and offers ununited elongation at running, especially for PVC conveyor belts and PU conveyor belts, which will lead to belt mistracking.
Solution:
In a case like that, you need to change a new belt and we suggest choosing good quality belts from reliable suppliers.
2. Badly connected belt joints
The belt joint is not straight and flat, resulting in uneven tension on both sides of the belt, and the belt deviates to the side with greater tension.
Solution:
Slight mistracking can be removed by adjusting the tension on both sides of the rotating drum or reversing the drum. If the belt tracking adjustment doesn’t work, the belt joint needs to be reconnected to ensure they are straight and flat. It is worth noting that to ensure the grooving of the belt at the joint, it is recommended to nail the belt buckle in sections along the length of the grooved roller when nailing the belt buckle.
3. Abrasion of belt edges
The belt may suffer irregular wear and tear in running and the elongation of both edges will have disparity as a result. With the disparity gap widening, belt tracking will be hard to maintain.
4. Aging belts
After the adjusted belt has been running for a period of time, due to the permanent deformation or aging of the belt stretching, the tension will drop, and the belt will loosen and cause mistracking.
Solution:
conveyor belt tracking solutions for the above 2 issues, you first need to evaluate if a belt is aged or damaged badly to be replaced. If yes, you can turn to another topic how to replace a belt. If not, the following is our suggested action: adjust the position of the rotating drum and the reversing drum.
Belt conveyors generally have more than 3 rollers, and the installation position of all rollers must be perpendicular to the center line of the belt conveyor in the length direction.
When the deflection is too large, belt mistracking will inevitably occur. According to which way a conveyor belt tracks, the roller shaft of that side will be moved forward along the belt running direction for a short distance by regulating the adjusting bolts of the bearings on both sides of the roller.
When the belt deviates at the tail reversing roller, the roller on the side where the belt runs loose should be moved forward along the running direction of the empty belt by adjusting the bolt.
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Improper Material Handling Affect Belt Tracking
The proper operation of loading material onto the belt is vital to ensure belt tracking. If the conveyor belt tracks well when it is empty, but always deviates to one side when it is heavily loaded, you need to check the reason why the conveyor belt has gone sideways. Here are some factors that should be taken into consideration.
5. Uncentered material loading site
Loading bulk material onto the center section laterally ensures good belt tracking. An uncentered loading site will result in uneven force along the belt sides vertically.
6. Impact of the feeding of bulk materials
When loading the belt, the weight of the bulk material as well as the inertia of the material hitting the belt will have a large impact on the belt, which possibly leads to belt mistracking.
7. Uneven distribution of bulk materials
If the conveyor belt tracks well when it is empty, but always deviates to one side when it is heavily loaded, you should check whether the material is evenly distributed on the conveyor belt or not. Uneven distribution of bulk materials also will affect the irregular force born by the belt and leads to belt mistracking as a result.
Especially when the projection of the upper conveyor and this conveyor on the horizontal plane is vertical, the impact is greater. So the relative height of the upper and lower belt conveyors at the transfer point should be designed properly.
The lower the relative height, the greater the horizontal velocity component of the material, and the greater the side impact on the lower belt. Meanwhile, it is difficult for loading the material onto the center. All these factors will disturb belt tracking.
Solution:
Reposition the material feeding site. The relative height of the two conveyors should be increased as much as possible in a reasonable range.
If possible, narrow the width of the guide groove to about three-fifths of the belt width, which is helpful for ensuring centered material loading. In addition, a baffle plate can be applied to reposition the site of material feeding.
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Belt Mistracking Caused by Conveyors
Above, we can see that among all conveyor belt tracking methods, the most approachable method is learning skills of conveyor belt tracking adjustment and how to align conveyor belts. If they don’t work, then we need to focus on the adjustment of the conveyor itself.
8. Material sticking to the pulley and idler
Some sticky materials like mineral powder will stick to the pulley and idler, which will enlarge the partial diameter of these components, causing uneven tension on both sides of the belt, and finally resulting in belt mistracking.
9. Wear and tear of pulley
During the conveying operation, the pulleys may suffer varied degrees of abrasion, which will result in different diameters and the belt will track toward the larger side.
Solution:
Clear the sundries stick to the pulley and repair or replace the worn pulley according to its abrasion condition. One more thing to do is to keep a regular cleaning routine of the conveying system, which will not only help to ensure the belt track but also can extend the belt’s life.
10. Centers of the nose, tail, and middle frame are not in a line
The centers of the head, tail, and middle frame are not on a straight line so that the longitudinal centerline of the belt is not perpendicular to the axis of the drum, which causes the belt conveyor to deviate during operation.
11. Pulley not perpendicular to the belt running Direction
Solution：
Repositioning the roller to ensure the axis of the roller is perpendicular to the longitudinal centerline of the tape and parallel to the horizontal plane.
It depends on the belt tracks to which side of the bearing seat. When a belt tracks towards the right side of the head pulley, its right-bearing seat should be moved forward, or you can move its left-bearing seat backward. When it tracks the left side, you can move forward its left-bearing seat forward or the right-bearing seat backward.
When it comes to the tail pulley, the belt-tracking solution goes to the opposites completely.
12. Improper position of idler rollers
A conveyor belt consists of many rollers, all of which should be parallel to the belt and vertical to the belt’s longitudinal centerline, or the belt will bear uneven force and track off its way.
When the symmetry between the centerline of the idler group and the centerline of the conveyor frame is larger than 3.0mm, or when the upper surface of the roller can’t be on the same horizontal plane or inclined plane, it can’t guarantee good belt tracking. The mistracking caused by idler rollers appears in the following 3 types.
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- The Idler station out of true alignment
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- The idler station rotated horizontally
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- The idler station rotated vertically
Solution:
True alignment of the idlers improves the running behavior of the belt and contributes to good tracking of the conveyor belt. If the belt tracking is disturbed by the incorrectness of the idler frame, you can move the idler rack on the side of the deviation a little toward the belt’s running direction. Generally, the mistracking can be corrected by moving a few idlers.
When the mistracking is serious, it is necessary to re-calibrate the idler frame to control the level error of the idler group within the allowable range.
If the belt deviation is caused by loose bolts fixing the idler frame, re-tighten the loose bolts to return good tracking.
13. Improper tension device
When there is no load or a small amount of load, the conveyor belt tracks well but will deviate when the load is slightly larger, which may be caused by improper tension.
Because the belt tensioning device doesn’t work properly, delivering different tension on both sides of the belt, and the uneven force eventually causes the belt to mistracking.
Solution：
Adjust the tensioning device to make sure its roller axis is perpendicular to the centerline of the belt conveyor.
You can prevent such issues from the very beginning by employing skilled engineers and conducting a test run strictly according to the standard steps.
14. Belt mistracking caused the skewed rack
If the center line of the rack is skewed and the left and right sides of the rack are tilted horizontally, the belt may be subject to a certain lateral pull, pulling the belt to one side.
Solution:
Adjusting the head and tail of the rack to ensure that the centerlines of its nose, tail, and center of the middle frame are on the same straight line. Or, worse, you need to reinstall the whole rack.
15. Belt mistracking caused by conveyor vibration
During operation, the belt conveyor will inevitably produce a certain amount of mechanical vibration. The faster the running speed, the greater the vibration, and the greater the possibility of the conveyor belt deviation.
For the belt conveyor, the vibration caused by the radial runout of the idler roller has a significant impact on the belt deviation of the belt conveyor.
Solution：
In addition to being perpendicular to the length of the belt, the reversing pulley at the tension point should also ensure that its axis centerline is horizontal. When the hydraulic cylinder is used for tensioning, the bearing seat of the tensioning drum should be translated at the same time to ensure that the axis of the drum is perpendicular to the longitudinal direction of the belt.
When the belt conveyor is running, if the tension of the belt is not enough, the belt will not deviate when it is empty or with a small load, and it will deviate when the load is slightly larger. A suitable tensioning device must be selected to ensure that the belt has sufficient tension. Tight force.
Conclusion
We hope all conveyor belt tracking solutions mentioned in this article can be helpful for you to handle belt tracking problems beforehand. So that, your conveying won’t be stopped frequently to affect productivity, and you can also save cost by cutting down your maintenance budget.
Sometimes, you need to combine these conveyor belt-tracking methods to adjust belt-tracking for a complicated problem that may be caused by diverse factors.
Besides these conveyor belt tracking adjustments, you are suggested to source quality belts from reliable manufacturers and suppliers, which will eliminate some belt mistracking causes from the root.
If this article hasn’t covered the problems, you faced when tracking a belt, contact us to get professional guides on how to track a belt from Bsbeltfactory experts with about 20 years of experience.
