Conveyor Belt Failure Modes

- Jan 20, 2019-

Conveyor belt conveyors are widely used in short-distance transportation such as mixing, crushing and screening equipment. Especially in coal mine production, belt conveyors are widely used in coal mining in uphill, downhill, smooth and peaceful lanes and inclined lanes in mining areas. The transportation of materials and personnel, especially in the production of large coal mines, is an indispensable device. Its use and maintenance is an important task in the maintenance and overhaul of equipment in coal mine production. The quality of maintenance directly affects the smooth progress of coal mine production.


During the operation of the conveyor, conveyor belt deviation occurs frequently for various reasons, which not only causes abnormal wear and damage of the leakage equipment, reduces productivity, but also affects the normal operation of the entire equipment. Therefore, it is a very important task to correctly judge the cause of the deviation of the tape conveyor belt and to eliminate it in time.


The root cause of the deviation of the conveyor belt with the deviation of the conveyor belt is that the force of the external force of the belt is not zero in the width direction of the belt or the tensile stress is perpendicular to the width direction of the belt. Due to the many factors that lead to the deviation of the tape, the deviation of the tape should be solved from the aspects of design, manufacture, installation, commissioning, use and maintenance of the conveyor.


The law of deviation is to run tight and not run loose, run high and not run low, do not run before running, that is, if the tightness of the two sides of the tape is not the same, the tape moves to the tight side; if the height of the tape is different , the tape moves to the higher side. If the device such as the roller holder is not mounted on the vertical section of the running direction of the tape, but the end is at the rear end (in the direction of the tape running), the tape will move toward the rear end.

3-0mm-pvc-black-conveyor-belt31275451352

dfc3edb7512c804f6373c7f5f2bbcd91_u=578013056,2843323963&fm=27&gp=0

The reasons for the deviation of the conveyor belt conveyor are as follows:


Conveyor's own factors:


(1) The difference in rigidity of the body is deformed under the load, so that the conveyor belt is subjected to uneven upward support force during operation to cause deviation.


(2) The rotation of the idler is not flexible, so that the conveyor belt is subjected to uneven frictional resistance during running to cause deviation.


(3) The parallelism and centering of the centerline between the rollers have an error in the installation, which causes the conveyor belt to offset the centerline conveyor belt to cause a deviation during operation.


(4) In the production, the conveyor belt has its own thickness and unevenness, and it is inevitable that the conveyor belt will be deflected when it is used.


(5) The conveyor belt is unqualified at the factory, its own bending deformation, uneven force at each point, causing deviation.


(6) When the conveyor belt is installed in the hot connection, the joint position is not correct, a certain angle is generated, and the connection error is large, so that the conveyor belt causes a deviation during the running process.


Human factors for installing conveyors


(1) The installation position of the machine head is improperly determined, and the deviation between the center line of the roller and the center line of the conveyor is large, so that a large inclination angle is generated between the conveyor belt and the horizontal line, and the conveyor belt causes a deviation during the operation.


(2) The deviation between the axis of the idler roller and the centerline of the conveyor is large, which causes a large inclination angle between the conveyor belt and the horizontal line, which causes the conveyor belt to cause deviation during operation.


(3) The installation position of the blanking pipe and the guiding trough is improper, so that the material is unevenly distributed in the width direction of the conveyor belt, and the load on the conveyor belt is uneven, which causes the conveyor belt to cause deviation during operation.


Method of adjusting the deviation of the conveyor belt The method of deviation adjustment should be determined according to the running direction of the tape:


(1) The deviation of the conveyor belt should be carried out during the no-load operation of the conveyor. Generally, the coal drum is unloaded from the head, and the empty section is first adjusted along the running direction of the belt, and the load section is adjusted later.


(2) Adjusting the tensioning mechanism method: If the tape runs away from the same side under no-load and heavy-load conditions, the tightness of the two sides of the tape is different, and the tension should be adjusted according to the law of running tight and not running loose. The screw or counterweight of the tightening mechanism, if the tape is deflected to the left and right and the direction is fixed, the tape is slack and the tensioning mechanism should be adjusted.


(3) Adjusting the drum method: If the tape is deflected at the drum, it indicates that the drum is under-level, the drum is tilted axially, or one end of the drum is at the front end. At this time, the horizontality and parallelism of the drum should be corrected. .


The conveyor belt runs off at the drum, and it is mainly adjusted from the following two aspects: First, there is an error in the height of the bearing seat at both ends of the drum, so that the axis of the drum is not horizontal, causing the conveyor belt to run off, and the roller can be adjusted and adjusted on the bearing seat. The axis is horizontal; the second is that the center line of the drum is not perpendicular to the center line of the conveyor. The position of the bearing seat can be adjusted to ensure that the center line of the drum is perpendicular to the center line of the conveyor.


(4) Adjusting the roller bracket (or frame) method: the conveyor belt can be adjusted in other places to adjust the rollers. At the roller, the offset tape is turned to the side and the roller is running toward the tape. Direction, move an angle, the size of the angle should be determined according to the operation of the tape.


If the conveyor belt always shifts to one side when no-load, the roller bracket on the offset side should be moved forward by 12 cm in the direction of the belt running or the other side roller bracket (or frame) should be raised appropriately.


(5) Removal of the sticky method: If the roller and the roller are partially adhered to the material, the diameter of the roller will be increased, resulting in an increase in the tension of the tape at the place, thereby causing a deviation, and the adhered material should be cleaned in time.


(6) Adjusting the gravity method: If the conveyor belt does not run off when it is empty, and always shifts to one side when heavy load, it indicates that the tape has been eccentric, and the position of the hopper or belt conveyor should be adjusted to make the tape Load to prevent it from going wrong.


(7) Adjusting the conveyor belt method: If the edge of the tape is seriously worn or the seam of the tape is not parallel, the tension on both sides of the tape will be inconsistent, and the tape should be re-trimmed or replaced.


(8) Installation of the offset roller method: If two sets of automatic centering roller (flat roller or groove roller) are installed on the conveyor, the deviation of the tape can be automatically corrected. For example, when the tape is deflected and rubbed on one side of the small stop roller, the bracket on the side should be moved forward in the running direction of the tape, and the other side will move backwards relatively, and the tape will move backwards. Move the roller side until it returns to the normal position.


(9) Installation limit roller method: If the tape is always offset to one side, the limit vertical roller can be installed on the frame on the deviation side, so that the tape can be forcibly reset on the one hand, and the vertical roller can be adjusted on the other hand. Reduce the tension of the offset side tape and move the tape to the other side.


(10) Installation of automatic correcting device method: Install an automatic correcting device on the conveyor to prevent the tape from running off.


Precautions for conveyor belt conveyor deviation


(1) When the conveyor is designed, one set of self-aligning rollers can be set for every 10 sets of rollers in the heavy-duty section, and one parallel-adjusting roller can be set for every 610 sets of idlers in the idle section. The conveyor itself is biased.


(2) When installing the conveyor, firstly ensure that the installation center of the conveyor and the installation position of the machine head are accurate, and that all parts of the conveyor are not inclined along the center line, and the whole body is required to be straight.


(3) Always check the deviation of the tape around the conveyor, and the phenomenon of grinding the edge of the tape is not allowed.


(4) The tape joint should be inspected frequently, and the damaged part should be cut off in time. The redo should be made perpendicular to the center line of the tape.


(5) Always check the rotation of the idler and replace the unqualified idler in time.


Strengthening the daily maintenance and maintenance of the tape can eliminate and reduce the deviation of the tape, which will play a very good role in improving productivity and improving economic efficiency.