Now the belt conveyor has become the main equipment for transporting bulk materials, and its use has a history of 200 years. In 1795, it was used in Europe and the United States to transport grain. After the twentieth century, the application of belt conveyor became more and more extensive, and it became the main transportation equipment for coal and iron ore. In some fields, it has replaced the common means of transportation of automobiles, ships and trains, which greatly saves transportation costs. Especially in recent years, with the development of industry and science and technology, the conveying characteristics of large capacity, long distance and high belt speed have become the mainstream of the development of belt conveyors. Belt conveyors are widely used in industrial fields such as metallurgy, mining, chemical industry, ports and power stations. Belt conveyors are mainly used in conveying bulk materials, and have transportation characteristics that other modes of transportation do not have, showing good economic performance. The main advantages of belt conveyors are as follows.
(1) Low running resistance. The idlers used to support the conveyor belt can be rotated, which greatly reduces the running resistance.
(2) Long conveying distance. Due to the design and installation characteristics, the conveyor belt can be transported over long distances, and the distance is generally not limited.
(3) Good economic performance. With the same transportation distance and the same weight of goods, the cost of belt conveyors is cheaper than other types of transportation equipment. And the cost of design, manufacturing, installation and maintenance is relatively low.
(4) The conveying inclination angle is large. The large inclination conveyor developed now can increase the conveying inclination angle to 60°-90°.
This is something that other types of conveying equipment do not have.
5) High speed. The belt speed used in China has reached 3.5-4.2m/s, which is fast and efficient. With the development of large-scale belt conveyor, in addition to the above advantages, there are also the advantages of high power, low power consumption, smooth operation of the transmission system, etc., so that its operation is safe and reliable, it is easier to control automatically, and the use cycle is long In order to achieve the best configuration of the conveying system, it should be optimized in the design process. Although the belt conveyor improves the conveying efficiency, reduces the cost, and also meets the needs of long-distance and large-volume transportation, it also makes its design more and more complex, considers more and more factors, and also increases the economic cost. At present, the design of belt conveyor mainly adopts traditional design methods, and is designed according to years of accumulated experience and design parameters. The traditional method can only be satisfied with the design of the short-distance conveyor, including the structure, size and processing and manufacturing, etc., but cannot analyze the dynamic problem of the system, and the motion characteristics in the conveying process are not involved. Especially for the new type of conveyor, the long-distance, high-speed and other conveying performance makes some of the original problems with little impact become prominent, such as the high cost of the whole machine, the running resistance problem in the conveying process, the selection of the drive motor and the abnormal tensioning of the belt.
6) Due to the different specifications and models of belt conveyors, the investment cost is different. In general, the longer the conveying distance, the higher the cost. Nowadays, long-distance conveyors are widely used, so it is necessary to carry out reasonable structural design and performance analysis to reduce costs. The main costs to be considered in the processing and manufacturing process of conveyors are: conveyor belts, drive motors, frames and idlers.
7) (1) Reduce the number of rollers. Depending on the belt type, width, and running speed, the design spacing of the idlers is different. The number of rollers directly affects the cost, so the spacing of the support should be reasonably designed, the relationship between the stability of operation and the cost should be considered, and the spacing of the support should be reduced as much as possible on the basis of ensuring the stability of the operation. The technology reduces the cost and reduces the resonance problem during the operation of the belt conveyor.
(2) Reduce the running resistance of the conveyor. The conveyor will produce running resistance and consume energy during operation, so it is necessary to reduce the running resistance as much as possible. The size of the running resistance is directly related to the quality of the processing, manufacturing and installation of the roller.
(3) Reduce the cost of conveyor belts. In the selection of conveyor belts, it is necessary to choose the type with low tension and low strength, which can reduce the cost of conveyor belts. The use of multi-point line friction drive method and segmented drive method can reduce the tension of the conveyor belt.
(4) Choose a reasonable drive system. The drive device is the energy power device of the conveyor, which often uses high power to meet the needs of the starting torque, but it will also produce the vibration problem of the conveyor. In order to reduce vibrations, researchers have developed new start-up technologies, which have been implemented using soft-start technology. At present, the commonly used soft start devices include frequency converters, speed-regulating hydraulic couplers and CST soft start devices, etc., which have greatly improved the economic benefits.
