| Belt conveyor is the main equipment for Bulk solid handing. It is widely usedin mining, port and food industries. Compared to other transportation equipment,Belt conveyors have many advantages,such as: long distance transmission,largecapacity,high efficiency,low energy-consuming, low operating cost advantages etc.And It is easy to achieve automation and centralized control. On many occasions Ithas replaced other means of transportation. With the development of thetechnologies, the demand of the belt conveyor is increasing. Now, to meet the needof the best benefit, we must solve the curve of belt conveyor, which is theimportant fact to widen theapplicability of the belt conveyor. The dynamicproblems of the belt conveyor are directly related tothe design and manufacture ofthe belt conveyor. As a result of this, a lot of countries or companiesare studyingthis problem. But nowadays there is no one to apply the dynamic design method tothe design of belt conveyor with horizontal curves. So this paper would make aresearch on the dynamic design problem of belt conveyor and optimize the designof its key components.This paper addresses this issue in a more systematic study. Identify the designprocess of the belt conveyor'curve section. The calculation model of the curveradius is derived on the basis of the mechanical analysis. And an engineeringexample demonstrates the calculation model.Adopting discrete finite elementmodel to establish the start-up process dynamic model of belt conveyor.Using theWilson method, which can keep steady irrationally, to solve the belt conveyordynamic equation. Dynamic characteristic of the system in start-up process isreceived. Based on the theory of optimize design, the mathematical model ofpully's structural optimization was received. In ANSYS environment, The optimizedesign variables and objective function along with the iterative optimization aregiven. Now the main content and research methods are described below: (1) On the basis of a lot of literature, The domestic and international research andapplication profiles long-distance belt conveyor were reviewed. Through acomparative study, pointed out the gap of the belt conveyor application betweenhome and abroad.Then elaborated the direction of development on the future.Introduced research results of the design theory for the curve section of the beltconveyor home and abroad . Summarized the dynamic analysis theory and methodsof belt conveyor system, and its steel structure design.Then brought forward thedirection of this study.(2) In the design of belt conveyor with horizontal curve, the belt tension and thedesign of the structure of curve section is the core issue. First this paper identifiedthe design and calculation process of the curve section. On the basis of themechanics analysis for the system with horizontal curve, deducted the calculatingformula for the radius of curvature. And the conclusions was applied to actualproject design"development of 9.8 km belt conveyor with horizontal curve".(3) Adopting discrete finite element model to establish the start-up and breakprocess dynamic model of belt conveyor. This model considers the viscouscharacter of conveyor belt; movement resistance of conveyor and the parametershave effects on movement synthetically. The method it adopts is: we fit togetherthe dynamic model of the conveyor belt unit in beeline-running segment,theconveyor belt unit in swerve-running segment, take-up equipment unit, driveequipment unitand break equipment unit to gain the dynamic mechanical model ofthe normal type belt conveyor system. Using the Wilson method, which cankeep steady irrationally, to solve the belt conveyor dynamic equation. Then verifiedthe accuracy of the model and the solution method by examples.(4) Based on the theory of structural design optimization, the structuraloptimization mathematical model of the pulley was established.The designvariables are cylinder shell thickness, radial plate thickness, roller shaft diameter,wheel length and wheels diameter. The contact functions are maximum overall effect ,the largest shell cylinder radial displacement and the maximum deflectionfor the roller shaft . Overall quality are the objective function. Optimized thestructure design of the pulley. Using the optimization module of ANSYS software,A pulley with changeless cross-section plate become the study object. Usingsub-problems approximation optimize mothod, this paper gave the changerules'plots that the optimize design variable and o ptimization objective function goalong with iterative times in the design process.Optimization results show that afterthe optimized process,the quality of the pulley dropped significantly and a morereasonable and reliable structure outgrew, achieved optimization purposes.This paper, combining domestic belt conveyor backbone enterprises: "development of 9.8 km belt conveyor with horizontal curve" project, researched anumber of key design outlines of long-distance, large-capacity belt conveyor forhorizontal curve.Through the mechanics analysis upon its curve section, researchedthe relation between the curve radius and the idler layout patterns. Set up thedynamic modeling of the belt conveyor. Analyzed the belt tension in the process ofstart-up and provided reference for the selection of belt tape.Researched thestructural optimization of the pulley, Under the condition that meet the functionalrequirements, can get a lower quality and reduce system costs.The study of this paper has important practical significance for raising the designlevel of long-distance belt conveyor with horizontal. |
