As the main equipment of material transportation, belt conveyor plays an important role in the development of port industry. Under normal circumstances, the belt conveyor in a closed cycle of stable operation, smooth transmission speed, but vulnerable to the influence of external factors, in the actual work may appear higher than the belt conveyor bandwidth 5% or more offset, that is, the belt running deviation. Once the belt runs off the track, it will cause transportation material scattering, damage the environment, and seriously lead to belt fracture. Therefore, on the basis of mastering the working principle of the belt conveyor, it is necessary to carefully and comprehensively analyze the reasons for the deviation of the belt, and formulate feasible strategies to ensure the safety and stability of the belt conveyor in the process of bulk material transportation.
1 Port bulk material belt conveyor working principle
Belt conveyor by conveyor belt, frame. Roller device. Tensioning device and transmission device and other parts, each part of the coordination between the work, to achieve the continuous transport of port materials, to ensure the good development of port material transport, belt conveyor has been widely used, greatly reduce the cost of manpower, but also improve the efficiency of bulk material transport.
Belt conveyor in the process of bulk material transportation, generally in accordance with the straight line layout, belt conveyor in the process of layout, can have a certain elevation on the horizontal surface, but the elevation Angle must be controlled under 180, to ensure that bulk goods will not fall or block on the belt conveyor. The bracket and spoke structure should be fixed on the frame structure according to a certain spacing, and the belt should be enclosed along the vertical axis of the frame. Under the influence of the tensioning device, there will be mutual force between the belt frame and drive rolling Jane, so that the uniform rotation, through friction to drive the material forward, the above is the basic working principle of the belt conveyor, through this way to complete the transport of materials.
In view of the current application of belt conveyor in port, belt conveyor has simple structure and low cost. Low energy consumption and convenient maintenance. In the practical application process, the belt conveyor has four characteristics:
(1) the type of port bulk cargo is very many, including coal mine, food, etc., the application of belt conveyor is quite extensive;
(2) in the belt conveyor to increase the High Temp Double Seal Skirting Rubber and other accessories, can meet the basic needs of port transport goods;
(3) The transmission process is relatively smooth, there is no interaction between the belt conveyor and the goods, so that the bulk cargo transport is very safe; The belt conveyor has the characteristics of large volume of transport, and can continue to transport.
2. Deviation of port bulk material belt conveyor
In actual operation, the ideal working state of the belt conveyor is the belt center line and the center line of the frame completely coincide, to ensure that the belt in the transportation of bulk materials, in the middle state. Once in the belt conveyor conveying goods, the belt center and the center line of the rack do not coincide, there is a belt deviation phenomenon, if the deviation value is higher than the allowable range, known as deviation fault.
Belt deviation phenomenon is common in the operation of belt conveyor. Will be caused by many factors, and once the wandering, fault will bring port bulk material handling serious adverse effects, not conducive to continuous running of belt conveyor, the damage is mainly manifested in the following four aspects:
1) enlarging the roller axial force and roll Jane, if you don’t get timely treatment and solve, can appear the phenomenon of channeling axis, significantly reduce bearing With life;
(2) Belt deviation will cause serious wear on one side of the belt, if not properly handled, it is likely to fracture;
(3) belt deviation will make bulk materials appear scattered phenomenon, not only increase the workload of maintenance staff, but also cause damage to the environment;
(4) if the belt of the belt conveyor is not handled in time, debris may accumulate inside the rolling Jane device. If this goes on, the rolling Jane part is not evenly stressed, and serious safety accidents will occur.
3. Fault analysis of belt deviation of belt conveyor
Roller is the belt drive and change the direction of the main power, each rolling Jane are bearing between the supporting rod, in the case of belt center line and the center line of the frame completely coincide, the belt conveyor bearing capacity. Maximum throughput, but also the most stable working state. In the case of no goods, the movement direction of the belt conveyor belt is mainly affected by gravity, belt center and frame center line overlap, the force on both sides of the middle line can neutralize each other, this time the belt will work normally in the middle of the belt conveyor, there will be no belt deviation phenomenon.
4 Design of deviation rectifying device for belt conveyor
4.1 Design of belt deviation detection device
If the belt deviation,which will touch the deviation detection device and it will signal, the relevant staff can process it in time. Deviation detection device is the implementation of grading detection, when the deflection angle in 150~30, deviation detection device will send a fault signal of level 1, and can use the performance of the correction device itself to adjust the belt conveyor; When the belt offset Angle is more than 30°, the deviation detection device will send a secondary fault signal, at this time the belt conveyor needs to stop working for a maintenance.
4.2 Design of belt rectifying device
If the belt conveyor belt deviation, there is no way to stop the equipment for the first time, which requires the use of deviation correction device, the belt deviation dynamic processing, to ensure the safety and stability of the belt conveyor in the process of operation. More commonly used deviation correction methods are the following 3: (1) adjust the Angle between the supporting system and the belt, so that the belt can automatically return; (2) correct the belt conveyor on both sides of the retaining plate and belt contact part, avoid belt friction caused by loss and deviation; ③ Adjust the position of the driving drum, adjust the position of the drum and the belt. The belt rectifying device studied in this paper is mainly to adjust the belt position by changing the offset Angle of the roller.
Through the analysis of the stress of the belt conveyor, it can be concluded that the deviation of the belt is not only related to the influence of the gravity of the cargo, but also closely related to the Angle of the roller on both sides of the belt conveyor. If the belt deviates to the left, the position of the belt can be corrected by increasing the deviation Angle of the left roller and reducing the deviation Angle of the right roller.
This device mainly uses the push rod to control the Angle of the roller. For different belt conveyors, the installation of the belt correction device can be divided into different types: if the transport distance of the belt conveyor is long, set ⅰ group of rollers in each 10 groups of trough roller bearing branch; If the belt conveyor transport distance is short, you can set up roller sets at both ends of the conveyor head and tail.
5. Practical application and effect analysis
After the belt rectifying device is designed, it is installed on the belt conveyor of a port, and after careful debugging and comprehensive analysis, it is applied. From the application so far, the belt rectifying device has an ideal operation effect and achieves the design purpose. In the actual application process, the number of belt conveyor deviation phenomenon is significantly reduced, to avoid the occurrence of loose material because of the belt deviation, belt wear phenomenon is reduced, improve the safety and stability of the belt conveyor operation.
The practical application results of the device can be analyzed and the conclusion can be drawn that when the belt deflection Angle is 150~30°, the correction effect can reach more than 80%; When the deflection Angle is greater than 30, the belt rectifying device can start the alarm device in the first time, which is convenient for the staff to stop for maintenance, reducing the probability of safety accidents and extending the service life of the belt 2-3 times. The deviation correction device improves the deviation problem of bulk material belt conveyor in port, and reduces the manpower caused by shutdown maintenance.
Belt conveyor is the key equipment for bulk cargo material transmission in the port, belt deviation as a common fault in the belt conveyor, the adverse impact on material transportation is larger, therefore, in the context of understanding the working principle of the belt conveyor. Carefully comprehensive analysis of the reasons and principles of the belt deviation, the design of the belt deviation correction device and put into use, according to the actual situation of the feedback, the correction device application effect is good, can improve the problem of the belt deviation.