Belt conveyors are a common type of transport machinery that uses tape as a continuous transport device for carrying and towing. The main principle of the completion of the transportation is the friction force, that is, the frictional force generated by the roller and the idler on the tape drives the operation of the tape, thus completing the transportation function, which is characterized in that the bearing and the transmission are all completed by the tape. From a mechanical point of view, the cause of irregular movement of the belt during transportation is also due to the imbalance of the friction force, that is, when the force on the belt is uneven, local frictional force changes, resulting in abnormal work, common It is a deviation.

1 Analysis of the cause of deviation

It can be seen from the reason of the deviation of the belt conveyor in actual production that there are two direct reasons for the deviation: First, the driving force on both sides of the transmission belt is unbalanced, resulting in inconsistency of the belt during the transmission process. Second, the rollers and rollers create a lateral force on the belt, causing the belt to travel off-line. The following two cases are analyzed.

1.1 The situation of uneven force on both sides

(1) There is an error in the installation and commissioning of the tensioning device of the device. If the tensioning device of the belt is not installed and debugged, the tension on both sides of the belt will be uncoordinated. Therefore, the deviation will occur during operation. The most common cause of deviation is the deviation.

(2) Material blanking is uneven during belt transportation. In the normal no-load operation of the belt conveyor, the condition is normal, and when the load is transported, the method is reversed. At this time, the investigation should be carried out from the material blanking, because this situation is also very common during the operation of the belt conveyor. Uneven feeding will lead to an increase in the local pressure of the belt, which will increase the friction. Naturally, there will be an unbalanced operation, such as the material shifting to the left and going to the right, and vice versa.

(3) The quality problem of the conveyor belt itself. The quality problem of the belt itself will also lead to uneven tension on both sides of the belt, such as: the belt itself is not straight, the joint is not uniform, etc., so the belt will be biased to the tension tension, in the belt joint and not straight The most serious.

(4) The belt is aging and slack. The belt is a material with elastic characteristics, so it will appear aging or permanent deformation after a period of use, and then it will cause slack and tensile force drop, which will lead to the inside of the belt. The stress appears to be uneven, causing a deviation.

(5) The roller or the roller is polluted. There are often some viscous materials in the material transported by the belt. This material sometimes sticks to the drum or the roller, so that the diameter or friction coefficient of the roller or the roller changes, and the tension of the belt is applied. There will be unevenness, which will cause the belt to run off. This situation is common in short-distance transportation.

1.2 The roller or the idler causes lateral force to cause deviation

Rollers or rollers that support the belt transport function cause positional deviation due to installation reasons, which may cause the belt to be affected by the lateral force during the transmission, and there are many factors causing this situation, such as the following.

(1) The position of the roller or the roller is displaced when it is installed. When the mounting position of the carrying roller deviates from the vertical line of the center of the belt conveyor, or when the perpendicularity of the drum axis and the center line of the belt conveyor is in error, the belt may be deflected to one side after being carried. In the position of the steering roller or the idler roller, the deviation is more serious, and the deviation will occur in both the bearing and the returning stage, and the more forward the phenomenon, the less obvious. If the driving roller causes such a deviation, it is more serious.

(2) The center line of the roller or the idler and the belt is misaligned, especially in the case where the tail of the machine is tensioned by the weight, the floating form of the drum is turned at the tail, so the deviation is easy to occur (3) the mechanical bracket appears Deformation. This situation is mainly caused by deformation of the frame, including high and low changes, centerline offset, etc., which will cause the belt to be biased by the lateral force.

2 Belt conveyor measures to prevent deviation

In view of the factors causing the deviation in the front, necessary and targeted measures should be taken in the production to prevent the deviation of the belt conveyor. Fundamentally, it is to eliminate the influence of uneven force and lateral force on both sides of the belt, so as to fundamentally improve the working performance of the belt conveying equipment. Therefore, the main measures to eliminate the deviation are to improve the installation quality and implement technical transformation. Improve the awareness of maintenance, etc., in order to ensure the safety and reliability of the belt conveyor. The specific measures are as follows.

2.1 Adjusting the roller system

When the belt conveyor sends the deviation, if the middle part is serious, then the roller system can be adjusted to adjust and adjust the deviation. In order to facilitate and adjust the mounting holes on both sides of the roller bracket to change the growth holes, this form can avoid the deformation of the frame or the unevenness of the material or the deviation of the belt conveyor caused by mechanical vibration.

2.2 Adjust the position of the drive roller appropriately

The drum is an important driving device for the belt conveyor, so adjusting the position of the drum can effectively prevent the belt from running off. In the installation of the drum type, it should be ensured that the position of all the rollers is perpendicular to the center line of the longitudinal direction of the belt, and if there is a human error in the installation, the deviation will be caused. However, the length of the drum for transmission is limited, so in the normal case, the shaft line of the transmission drum can be adjusted to be perpendicular to the longitudinal direction of the belt conveyor, and then the position of the tail roller socket can be adjusted by adjusting the screw or the weight. This avoids the deviation caused by the slack of the belt and the deformation of the frame.

2.3 Setting the centering roller mechanism

When the conveyor belt is out of deviation, if there is a deviation in the middle, another method can be used to control and prevent it, that is, adding a self-aligning roller to the device to prevent it. The principle of this mechanism is to use the rotation of the roller on the horizontal surface to generate a lateral force, so that the roller mechanism rotates in a circular arc around the central axis, and the belt automatically moves toward the center according to the situation that the belt is not perpendicular to the roller when running. This completes the adjustment of the deviation. This method is usually applied on shorter belt conveyors.

2.4 Adjust the tension of the belt

The tension is also a factor that affects the deviation of the belt. Therefore, it is possible to use a reasonable method to control the deviation according to the difference of the tensioning mechanism. In the heavy hammer tensioning mechanism, it can be divided into tail tensioning and middle tensioning, while mechanical tensioning refers to screw tensioning. In the form of heavy hammer tensioning, the steering drum treatment requirements are perpendicular to the longitudinal direction of the belt and should also be perpendicular to the vertical line of gravity of the weight to maintain the level of the axis. When the screw is tensioned, the center line needs to be perpendicular to the longitudinal direction of the belt regardless of the position of the tension roller.

2.5 Adjusting the transfer point and blanking position of the material

The transfer point of the material is the position for transit during transportation. It is the transfer between two belts or other material transmission forms and the belt. The transfer position and the falling position of the material will affect the force of the belt, so adjusting its position can avoid The belt runs off. First, the height between the two belts at the transfer point should be controlled. The impact force of the material with a relatively high level of low level and high speed is greater, and the material usually does not fall to the center of the belt. This will cause the material on the belt to be unevenly weighted and uneven. Will cause the belt to run off. Therefore, when installing two reversing belt conveyors, the relative height between the two belts should be increased. At the same time, the shape of the funnel, the guide trough and the amount of discharge should be calculated and controlled. Generally, the width of the guide trough is 2/3 of the belt width. Preferably, the position, orientation and adding means of the blanking can be changed to help the material to be even and to prevent deviation.

3 Conclusion

In summary, in the process of preventing belt deviation, we must first adjust the hardware of the equipment, optimize or adjust from the drum, idler, tensioning device, etc., so that it can improve the adaptability to the working environment, and from the external environment. Adjust the way the materials are added, so that comprehensive measures can be taken to prevent belt deviations from being comprehensive and safe to avoid accidents.

Efficient Air Flotation

Wuxi Feiyiya Environmental Protection Technology Co., Ltd. , https://www.fefinegrille.com