Research On Design Of A Long-Distance Belt-Conveyer In Down-Transporting With Varying Slope

Based on the design method for the conventional Downwards Transporting Belt-Conveyer(DTBC), the common used driving and braking devices were analyzed in the condition of long-distance and heavy-capacity. The driving and braking types were presented for this kind of conveyer. The soft-starting devices and their type-selection were analyzed. The key points were summarized for designing the long-distance, heavy-capacity DTBC used in varying slope environment. The reliable combined scheme of driving and braking units was put forward. The methods for determining the tensioning location, type and the amount of tensioning force based on the results of conventional calculations. The criterion was summarized for selecting driving device and the main components in the conveyer. By dynamical model and simulation of the conveyer system, the conclusion of static design was combined with the results of dynamical analysis. The problems, which exist in this kind of conveyer during its starting, operating and braking processes, were pointed out. The feasible control scheme was presented. It was proven by the engineering test that the control scheme was practical and reasonable, which would found the base for DTBC's design and application. The main points of the paper were described as follows.1. The dynamical performance of the conveyer can not be ignored under the situation of long distance, heavy capacity and large power. It is the only effective means to add soft starting device. Only when the acceleration is small enough during the starting period, the operation of the conveyer will run smoothly and without serious shock.2. Due to the complicated operational condition of long-distance and varying slope DTBC, it is necessary to consider every kind of possible working conditions during its design and calculate the parameters in the most dangerous condition. At the same time, it isnecessary to uniform the tensioning force in order to suit the variations of the load and condition. Then the conveyer's parameters should be re-calculated under various conditions and the parameters could be determined finally.3. It was put forward that the combination of controllable braking device and controllable soft starting device could be used in long-distance DTBC. The control scheme could be determined based on the signal from the sensors. The controllable starting and braking of the conveyer could be realized by carrying out the control scheme.4. Determining the accelerating time by dynamical simulation and directing the practice by the simulating conclusion were proven feasible and effective from the practical test.The research of this paper shows that by using reasonable combination of driving scheme, braking mode and soft-starting device and by determining the schemes for braking and soft-starting from the dynamical analysis and simulation, the reliable operation could be guaranteed for the long-distance, heavy-capacity and varying slope DTBC. The conclusions of the paper would be significant in theory and practice for the future development of this kind of conveyer.