Modelling of belt conveyor movement considering the inclination angle and tension of the ropes of the load bearing structure

Introduction. The relevance of the work is caused by the need to eliminate the arising automatic vibration processes of the pendent roller of the conveyor linear sections relative to roller pendant and minimization of vibration synchronization processes of a significant number of pendent rollers, leading to a conveyor stop. Previous studies have established that the most effective way to transport coarse material in underground mining is a belt conveyor. These studies have identified the disadvantages of conveyor transportation.The most common ones include the auto-vibration of the pendent roller of the conveyor linear sections relative to roller pendant. The manifestation of roller automatic vibrations increases the energy intensity of the process and reduces the performance of the belt conveyor. Objective. To set the angle of the conveyor belt inclination and the tension of the ropes of the load-bearing structure with the lowest amplitude vibrations of the pendent roller in order to reduce the energy intensity of the transportation process during the deposit development and increase the operational performance of the conveyor. Task. Modeling the possibility of manifestation and causes of occurrence, as well as the circumstances of long-term preservation of roller automatic vibrationson conveyors. Materials and methods of research. The object of the study is a conveyor belt with different angles of inclination (transportation).The authors conducted analysis and summary of previously performed own research; comparison with newly obtained experimental results; as well as a generalization of theoretical and experimental studies carried out by scientists in this field; synthesizing literature and patent data. Reliabilityis confirmed with application of actual state standards and approved research methodology. Boundary conditions are accepted: conveying of ordinary medium- and small- sizedmaterials is carried out; there is a constant unit load on the belt during transportation. Two types of connection are considered: the presence of an anchoring branch of roller with the ropes; absence of an anchoring branch that is the hinged connection of roller with the ropes. Research results. It has been established that when the belt moves with a load, the pendent roller deflects along the direction of the belt movement, regardless of the type of anchoring. The angle of the side roller inclination is calculated through the sliding velocity relative to the belt. The characteristics of sliding friction or change in sliding friction coefficient are modeled. The influence of the pendent roller mass on the process of automatic vibrationsat various angles of conveyor inclination has been evaluated. The reason for the occurrence of automatic vibrationsis established. Conclusion. Design changes that prevent side roller misalignment are recommended to reduce the likelihood of automatic vibrations.The side roller misalignment angle interval, beyond which stable conveyor operation is achieved, is determined. Resume. The results of the research can be useful in designing the conveyor when transporting the extracted raw materials.