Status and development trend of belt question in mind: Responding to many of our domestic national standard bidding and tender specified in a foreign country supporting documents (as specified by foreign reducer, motor and even roller, etc.), even picked <> on "Status and development trend of belt conveyor," a paper for the sake of friends, colleagues, and of course the past 15 years, foreign to the theory of belt conveyor made great progress, the main components of belt conveyor The technical performance has improved markedly, as the long-distance belt conveyor, the direction of large-scale basis. With the availability of long-distance belt conveyor * and the continuous improvement of economic requirements, the design ideas are developed gradually. Advanced design ideas, based on international standards ISO 5048 and the German industrial standard DIN 22101, based on trying to reduce the running resistance, and reasonable safety factor to determine the conveyor, the use of controlled, the braking device smooth starting and braking, the use of transport viscoelastic theory with dynamic analysis carried out on the conveyor prediction and optimization of working conditions. However, there is still a significant and abroad, a considerable gap, I believe the future of our domestic counterparts units can also be to the world. . .Abstract: The present situation at home and abroad and development gap between the belt conveyor, in particular, the core technology of large belt (including the belt dynamic analysis and monitoring techniques, controlled soft-start technology and power equalization technique), equipment performance and reliability, life, etc., discussed the development trend of belt conveyor technology.Keywords: belt conveyor; the status quo; DevelopmentIn number: TD528 Document code: A1, the status of foreign belt conveyersForeign belt technology has developed rapidly, and its mainly in two aspects: one is the function of belt diverse range of applications expansion, such as high angle conveyor belt, pipe conveyor, space turning conveyor and other models; the other hand is the belt itself has great technology and equipment development, especially long-distance, large capacity, high speed and other large conveyor belt has become The main direction of development, the core technology used in the belt is the development of dynamic analysis and monitoring technology to improve operational performance and reliability of the belt. At present, the coal mine belt use has reached as shown in Table 1, the main technical indicators, the key technology and equipment has the following characteristics:⑴ large-scale equipment. The main technical parameters and equipment are toward large-scale development to meet the annual output of more than 300 t ~ 500 million high yield intensive production.⑵ using dynamic analysis techniques, and mechanical and electrical integration, computer monitors and other high-tech, using high-power soft-start and automatic tensioning technology, conveyor dynamic monitoring and control, greatly reduces the dynamic belt tension, equipment operating performance transport efficiency.⑶ multi-drive with the intermediate driver and the power balance, conveyors and other technical changes to the operation, the length of the conveyor run single in theory have been restricted, and to ensure that the common carrier system equipment and interchangeability of units drive reliability.⑷ new, high-reliability critical components technology. Such as the CST, etc., contains a variety of advanced high-power drive and speed control devices, high-life high-speed roller, self-cleaning drum device with high storage device, such as rapid self-moving tail. Such as the UK FSW production FSW1200 / (2 ~ 3) × 400 (600) working face conveyor on the use of a liquid or viscous differential frequency control devices, transport capacity of 3000 t / h or more, it's machine tail with the new loader (such as the U.S. Joy produced S500E) matching can be automatically and quickly with the passage from the face shift, less manual work, high production efficiency.Table 1 The main specifications of the foreign Belt300 ~ 500 million of foreign t / a high yield and efficiency of mineMain parameterTrough retractable belt roadway and inclined belt conveyor stationary strongDistance / m 2000 ~ 3000> 3000With speed / m.s-1 3.5 ~ 4 4 ~ 5, up to 8Throughput / t.h-1 2500 ~ 3000 3000 ~ 4000Drive the total power / kW 1200 ~ 2000 1500 ~ 3000, the maximum of 101002 Status of domestic belt conveyersChina's manufacturing belt of the variety, the type more. In the "Eighth Five-Year" period, through the national one-stop "Nissan tons of mining equipment," implementation of the project, the belt conveyor technology has greatly improved, coal mine with high power, long-distance belt conveyor key technology research and development of new products have made great Lu progress. As long inclined belt conveyor equipment, high efficiency working face retractable belt Dengjun to fill the gap, and the key technologies and the reduction of belt conveyor components were mainly theoretical study and product development, successfully developed a variety of soft start and brake devices and the PLC as the core of the programmable electronic control devices, variable speed drive system using fluid couplings and planetary gear reducer. At present, China's coal mine belt conveyor Main technical characteristics of indicators shown in Table 2.Table 2, the main technical indicators of the domestic beltTrough the main parameters of roadway with retractable belt Force Belt Fixed ShaftDistance / m 2000 ~ 3000> 3000With speed / m.s-1 3.5 ~ 4 4 ~ 5, up to 8Throughput / t.h-1 2500 ~ 3000 3000 ~ 4000Drive the total power / kW 1200 ~ 2000 1500 ~ 3000, the maximum of 101003, the gap between domestic and belt conveyers3.1 The core technology of a large belt the gap between the key⑴ belt dynamic analysis and monitoring long-distance, high-power conveyor key technology is a dynamic design and monitoring, which is the core of restricting the development of large belt conveyor technology. At present our analysis of the theory with the rigid belt and to develop calculation methods and design specifications, the design of the Shu Songdai use high security systems (general admission n = 10 or so), a far cry from the actual situation. Conveyor belt is a viscoelastic material fact, long distance on the conveyor belt drive device, the braking force of the dynamic response is a very complex process, and can not simply be explained by rigid body mechanics and computing. Has developed a method of belt dynamic design and application software, in large conveyor conveyor on the dynamic analysis of the dynamic tension and dynamic monitoring and reduce the safety belt system, greatly extend the service life, ensuring a reliable conveyor operation nature, so that the large belt conveyor designed to meet the highest level (belt safety factor n = 5 ~ 6), and to the conveyor belt equipment costs, especially costs greatly reduced.⑵ reliable power controlled soft-start technology and long distance and large capacity belt conveyors Balancing the power of large, long distance and multi-drive, soft start approach must be used to reduce the transmission mechanism of dynamic tension, especially when the multi-motor drive . In order to reduce the impact on power, soft start Shiying a time-slow start; also controlled conveyor starting acceleration 0.3 ~ 0.1 m/s2, to resolve carrier tape and the drive belts and conveyor belt speed synchronization swell phenomenon components to reduce the impact. Electrical characteristics due to manufacturing errors and error, the driving point there will be no balance of power, once a motor power is too large will cause burning motor accident, therefore, the power balance between the motor should be controlled, and improve balance accuracy. China has a large number of applications of variable speed fluid coupling to achieve a soft start conveyor and power balance, to solve the long-distance belt conveyor starting with the power balance and synchronization issues. However, the accuracy and reliability of its regulation, there is still a certain gap with foreign countries. Moreover, in addition to long-distance high-power requirements of a coal conveyor belt speed, but also need a test with the belt speed, variable speed fluid couplings although soft-start and power balance, but the need for long-range development the hydraulic stepless speed control device. When the stand-alone power> 500 kW, the controlled soft-start show the superiority of CST. Controlled soft-start is the planetary reducer inside the ring with a combination of wet friction clutch (ie, viscous drive). Through the proportional valve and control system to achieve the soft start and power balance, the regulation accuracy of up to 98%. But very expensive, much-needed domestic.3.2 The gap between the technical performanceOur main performance parameters of the belt conveyor can not meet the needs of high yield and efficiency of mine, especially along the key slot retractable belt conveyor components and their functions, such as self-moving tail, efficient storage and tensioning devices with have a big gap with foreign countries.⑴ installed power of working face to the maximum installed power telescopic belt conveyor 4 × 250 kW, up to foreign products, 4 × 970 kW, installed power belt conveyor made foreign products is about 30% to 40% fixed belt conveyor installed power difference even greater.⑵ transport capacity of the largest volume for the belt conveyor 3000 t / h, abroad reached 5500 t / h.Maximum width of conveyor belt ⑶ is 1400 mm, maximum foreign 1830 mm.⑷ with speed limits as trustee roller speed, our conveyor belt speed is 4m / s, foreign to 5m / s or more.⑸ transport length of working face to 3000 m, abroad for the 7300m.⑹ self-moving tail with the continual emergence of high efficiency face, asked trough belt conveyor tail scalable rapid progress with the face of rapidly self-moving. China mainly relies on the tail from the shift of imports, there are two kinds: (a) moving along with the loader produced by the British LONGWALL tail unit from moving. (B) produced in Germany since DBT transfer tail device. The former is only one forward cylinder, the latter two advancing tanks. LONGWALL produced in the country claiming the bandwidth used for the tail conveyor 1.2 m, the disadvantage is that since the shift amount of the tail belt is too small deviation, correcting weak, poor rigidity. German production of the self-moving tail used in the country better than the former, horizontal and vertical directions have two fuel tanks of offset, corrective ability. Thus, the former needs to improve, which need development. However, since the shift of the requirements of the tail is common, it is necessary to meet normal working hours conveyor slip requirements, but also to meet in the conveyor without stopping the case from moving fast.⑺ efficient storage zone and the tensioning device in a closed reservoir of the band structure and the main winch red tight, tension easily derailed car, conveyor belt and easy wandering, telescopic conveyor, the roller is not self-moving car, went on to be artificial, maintenance problems. Foreign use of the structure of open storage with advanced devices and high-torque high-precision, large travel automatic tensioning equipment, roller conveyor with retractable car automatically in place. Conveyor belt are easy to deviation, will not derail the phenomenon.Variety of models ⑻ conveyor few varieties, single function, use of restricted and can not give full play to its effectiveness, such as the expansion of a carrier, or two-way haul transport and other functions, make use of a machine; In addition, differences in geological conditions of coal mines great layout of the transport system often will be some special requirements, such as bending, large angle (> +25 °) until the vertical lifting, etc., should be developed machines of a special type of belt conveyor.3.3 The reliability of the gap between life⑴ conveyor belt fabric tensile strength of the entire core of the production of flame-retardant conveyor belt up to 2500 N / mm, abroad for the 3150 N / mm. Steel cord conveyor belt flame retardant up to 4000 N / mm, abroad for the 7000 N / mm.⑵ conveyor belt joint strength, joint strength as a master of the 50% to 65%, 70% of foreign of mastering 75%.⑶ idler roller life of our existing technology and foreign comparison, life is short, low speed, resistance, and the United States using the new oiling roller, the running resistance, bearing with oil lubrication, greatly improved the care roll life, and can be applied as a high roller conveyor, using a wide range of significant economic benefits. Conveyor roller of life 20,000 h, the foreign life roller 5 90 000 h, only foreign-made products roller life of 30% to 40%.⑷ conveyor conveyor gear reducer life life of 20,000 h, 7 million foreign gear life h.⑸ poor reliability belt running up and down3.4 The gap between the control system⑴ drive for the speed of fluid couplings, and hardened gear, foreign transmission and diverse, such as the BOSS system, CST controlled transmission, and control accuracy.⑵ conveyor monitoring device has been adopted abroad, high-grade programmable logic controller PLC, developed a sophisticated software program with integrated power relay Bo and data admissible control, processing, storage, transmission, diagnostics and query the full automatic control system. China conveyor using only mid-range programmable logic controller to control the conveyor's start, normal operation, shutdown and other works. Although the start with the control (system) used in conjunction with supporting devices, to control Kai (system) moving with speed synchronization, power balance and other functions, but not near the device automatically, without fault diagnosis and inquiries.⑶ conveyor belt in addition to installing protective devices to prevent the conveyor belt of foreign deviation, slip, tear, too full of congestion, dust and other automatic sprinkler protection, in recent years has developed many new monitoring device: drive pulley, change to the drum and idler temperature monitoring system; smoke alarms and automatic fire extinguishing equipment; fiber woven Shusongdaizong avulsion and joint monitoring systems; proof electronic Shusong Dai scale automatic metering system. These new protection system base in the blank in China. In China, the current skid, the heap of coal, Coal Chute warehouse full of protection, anti-deviation, over-temperature sprinklers, smoke alarm device reliability, sensitivity, life expectancy is relatively low.4 Coal Belt Conveyor Technology Trends4.1 The large-scale equipment to improve the transport capacityIntensive production in order to meet the needs of high yield and efficiency, to increase the transmission capacity of belt conveyor. Long distance, high belt speed, large capacity, high power is the inevitable trend of future development, but also high efficient mine transportation technology development. 10a in the future to increase the throughput to 3000 ~ 4000 t / h, speed also increased to 4 ~ 6m / s, the length of the retractable conveyor belt to reach 3000m. For the steel cord to be extended to 5000m Force Belt over single drive power required to achieve 1000 ~ 1500 kW, belt tensile strength 6000 N / mm (steel cord) and 2500 N / mm (steel cord .) Especially coal mine trough the development of scalable delivery technology, with the emergence of high efficiency face and the continuous development of coal technology, the original retractable belt, whether it is the main parameter, or operating performance are difficult to adapt to high efficient face the requirements of the main parameters of the mine site need more, more advanced technology, performance and more reliable long-distance, large capacity, high-power retractable conveyor trough in order to improve the design of belt conveyers level, fill the gaps, close and catch up with international advanced technical level of industrial countries. Which includes seven key technology areas: ⑴ belt dynamic analysis and monitoring technology; ⑵ soft start technology with the power balance; ⑶ intermediate driver technology; ⑷ automatic tensioning technology; ⑸ new high-life high-speed roller technology; ⑹ fast Since the tail of technology transfer; ⑺ efficient storage with technology.4.2 improve performance and reliability of componentsEquipment operation rate of the high and low components depends on the performance and reliability. In addition to further improve and enhance existing performance and reliability of components, but also constantly developing new techniques and components, such as high performance controlled soft-start technology, dynamic analysis and monitoring technology, and efficient storage with the device, rapid self- Move the tail, high-speed roller, so that the belt has been further improved the performance.4.3 The expansion of functions of a machine ofExpand the transportation of people, or two-way haul transport and other functions, so that a machine so as to maximize economic benefits. Development of special type belt conveyor, such as the curved belt conveyor, inclined or vertical lift conveyors.