关 键 词：

输送 传动 装置 设计

资源描述：

带式输送机传动装置设计,输送,传动,装置,设计

内容简介：

封面样式湖 南 科 技 大 学英文文献翻译学 生 姓 名： 学 院： 机电工程学院 专业及班级： 机械设计制造及其自动化四班 学 号： 指导教师： 2015 年 6 月 6 日国内外带式输送机动力学与控制宋伟刚摘要：分析国内外带式输送机动力学的研究进展与方法，进而给出动力学分析的基本方法与过程。关键词：带式输送机；动力学模型；动态分析1 .带式输送机的设计计算方法与动力学问题带式输送机是当代最重要的散状物料输送设备，广泛地应用于煤炭、钢铁、电力、建材等工业领域，也是港口、料场等物流系统中散料存储、输送的重要装备。带式输送机的设计计算方法的发展经历了漫长的历史，作为机械设备的带式输送机其设计计算方法和其他机械系统类似地，计算式可以从基本的力学定理、物理学法则所得出。其进展随着理论研究的深入，计算手段的进步越来越细致与精确。最早可以见到的计算方法是德国HETZL方法，另外，一些公司也提出了较有影响的计算方法，如美国的GOODYEAR公司、GOODRICH公司和日本的阪东橡胶公司等计算方法，这些计算方法的主要阻力计算都属于概算法。20世纪的50年代，德国的LACHMANN和VIERLING教授提出了精确计算主要阻力中各个分项的计算方法、80年代以后荷兰的SPAANS教授、美国的CDI公司进一步发展了精确计算主要阻力中各个分项的计算方法，他们都是从带式输送机主要阻力的构成角度得出相应的各个分项。然而精确计算方法当前仍然极少采用，即使在德国标准中。 从功率和张力计算过程看，出现过两种不同的方法：一种方法是根据输送带垂度条件确定传动滚筒奔离点张力，再采用逐点张力计算方法计算出传动滚筒相遇点张力，滚筒上的张力差就是所要求的驱动功率。早期的苏联计算方法和TD75、DX带式输送机设计手册7-9主要是采用此类方法；另一种是直接将各种阻力叠加在一起得出输送机总的功率需求，进而通过输送带和滚筒不打滑条件和垂度限制条件按逐点计算方法计算输送带各特征点张力。在当前带式输送机设计计算的主导方法德国标准DIN22101-2002和CEMA(第5版)带式输送机功率和张力计算方法。DIN22101计算方法属于上述的第2类、而CEMA计算方法介乎第1和第2类之间，这是由于该方法考虑到运行阻力和张力相关。从上述方法的分析可以看出，计算结果的是否准确的关键问题并不取决于计算次序，而在于输送机运行过程中的阻力计算是否准确。带式输送机的运行过程由启动-稳定运行-停机构成，尽管一条输送机在绝大部分时间处于稳定运行或停机状态，但是由于在启动和停机过程会有加速或减速产生惯性载荷，因而在输送机的设计中需要考虑动载荷的影响。传统的设计计算方法(如DIN22101)是将输送机上所有运动部件看成刚性联结在一起，同时加速或减速(可以看作“准静态”)，不考虑输送带的粘弹性性质以及在启动、停机过程中驱动的输入力(矩)随时间变化的作用，从而不能给出输送机在启动、停机过程的瞬态过程。从带式输送机的瞬态过程角度来看，在下列几个方面存在动力学问题：(1)输送机的启动、停机过程的输送机纵向的速度和应力(张力)的传播 带式输送机(特别是大型带式输送机)的结构特点体现在：输送带、托辊和物料是散布在输送线上，输送带本质上是粘弹性体，因而驱动装置的启动过程是逐渐地将驱动力和速度传播到整个输送带上，输送机的启动是一个渐进的过程，输送带的张力由静止状态下的张力变化到稳定运行下的张力，张力的变化导致输送带的变形量的变化，由拉紧装置的伸长或缩短和输送带的挠度变化所吸收。另一个特点是多驱动单元与多点驱动。当没有考虑到纵向动力学瞬态过程的影响可能出现的问题包括： 1)选择过大的驱动设备的投资费用过高，造成启动和停机过程中的输送带的张力过大；2)变坡线路的带式输送机停机过程中造成输送带的局部张力过小；3)拉紧装置的位移设计的不准确，出现拉紧行程不够或拉紧反应滞后，不能满足系统的传动要求；4)驱动装置、制动装置和拉紧装置的配置与位置布置不合理；5)在多驱动单元系统中启动或制动过程中由于加载次序与时间控制上的问题产生振荡，造成各驱动单元的输出无法实现同步与功率平衡。(2)输送带在横截面上的垂直于输送带面的振动输送带在张力、载荷和输送带固有特性下，当托辊的激振频率与固有频率接近或一致时，在输送带的横截面的铅垂面方向存在振动问题，此振动将会使输送机机架甚至建筑物发生破坏12-14。(3)输送带在输送机横向的跑偏输送带跑偏是广泛存在的问题，跑偏是引起输送机停机、撒料、机架堵塞、输送带使用期限缩短等后果的主要原因，跑偏的调整是非常麻烦的事情，从理论上对跑偏分析方法是建立输送带横用运动动力学方程，进而应用稳定性理论进行分析。(4)输送物料量的变化引起的运行状态的变化输送物料量的变化会引起运行状态的变化，然而这种变化相对于输送带的波动周期要长得多，因而一般不会单独对此问题进行研究，研究的关注点是不同物料载荷分布下的纵向波动问题。(5)受料过程物料对托辊和输送带的冲击输送带受料处物料冲击(特别是大块物料)的冲击直接危害带式输送机的正常使用，是输送带损坏的重要原因，导致输送带发生磨损、上覆盖层、带芯、甚至是整个输送带的击穿，致使输送带的损坏和撕裂，增加托辊的冲击载荷。(6)输送带经过托辊的输送带覆盖层的挤压变形与恢复输送带下覆盖层在输送带的挤压变形是产生输送机主要阻力中的压陷阻力的原因。从带式输送机的控制角度来说，除满足带式输送机满足工艺要求的顺序控制与不同输送量下的速度改变以及对带式输送机的保护控制外，主要的控制要求仅体现在对输送机瞬态过程的控制。从上述的分析可见，带式输送机动力学问题涉及带式输送机系统的各个方面，本文将重点讨论上面所列问题的第(1)方面，而对其他5个方面的问题仅做简要探讨。首先分析国内外的研究进展与方法；进而给出动力学分析的基本方法与过程，包括：数学模型、求解技术、软件的发展；典型带式输送机系统的动力学分析、动态分析的作用及其应用范围等。动力学研究的主要内容与方法： 带式输送机的动力学分析与动态设计方法的研究与应用之所以受到广泛的关注，是由于随着带式输送机系统的大型化，传统的半静态设计计算方法已经不能满足工程实际应用的需求。另一方面，动态设计方法的采用有助于提高设计水平，达到提高企业竞争力。动态设计与动态优化设计也是面向产品广义质量的综合设计方法96的重要组成部分。因而，带式输送机的动力学与动态设计方法涉及到带式输送机的所有方面，即：1)带式输送机各个运动部件的力学性能，特别是输送带；2)输送机运行阻力的计算方法及其规律性问题；3)驱动、制动、拉紧、传动装置的结构与特性以及控制方法；4)带式输送机各运动部件的数学模型以及由各个部件的数学模型所构成的整机模型；5)所建立的动力学模型的求解方法与软件开发；6)各种驱动装置、制动装置和拉紧装置动态响应对启制动特性的影响；7)复杂带式输送机系统各种运行工况下动态行为研究，包括启动、制动、上运、下运等；8)各种工况下的现场测试分析，控制系统的动态调整。Dynamics and Control of Belt Conveyor at Home and AbroadSONG Wei-gangAbstract: analysis of the belt conveyor dynamics both at home and abroad research progress and the method, and dynamics analysis of the basic method and the process is given.Key words: belt conveyor; Dynamic model; A dynamic analysis1. The belt conveyor and the design method of dynamic problems Belt conveyor is the most important contemporary material conveying equipment, widely used in industrial area, such as coal, steel, power, building material, port, yard logistics system such as releasing the importance of materials storage, transportation and equipment. The development of the design and calculation method of belt conveyor has experienced a long history, as the belt conveyor design calculation methods of mechanical equipment and other mechanical systems similarly, calculation formula can be from basic mechanics theorem, obtained from the laws of physics. Its progress with the deepening of theoretical research, the calculation method of progress more and more detailed and accurate. Is the earliest can meet the calculation method of German HETZL method, in addition, some companies are put forward and the calculation method of influential companies, such as Americas GOODYEAR GOODRICH and Japan e. calculation methods, such as east rubber company, the main resistance calculation of these calculation methods are approximate method. The 50 s of the 20th century, the German professor LACHMANN and VIERLING presented the calculation method of precise calculation of the main resistance of each component, SPAANS professor after the Netherlands in the 80 s, the United States of CDI company in the further development of the precise calculation of the main resistance and the calculation method of each item they are from the Angle of the composition of the main belt conveyor resistance of the various disciplines. Accurate method to calculate the current still rarely used, however, even in the German standa From the power and tension calculation process, there have been two different methods: a method is based on a conveyor belt sag condition determine the transmission drum ran away from the point of tension, then use point by point tension calculation method to calculate the transmission drum meet some tension, tension difference of the roller is the driving power required. The calculation method of the Soviet union and early TD75, DX belt conveyor design manual 7-9 is mainly adopted such methods; Another kind is the superposition of all kinds of resistance directly together conveyor total power demand, and then through the conveyor belt and roller not skid and sag restriction conditions according to the point by point calculation method to calculate the conveyor belt tension of the feature points. In the current belt conveyor design and calculation the dominant method of Germany and CEMA standard DIN22101-2002 (fifth edition) power belt conveyor, and tension calculation method. DIN22101 calculation method belongs to the second class, and CEMA calculation method between 1 and 2 class, this is due to the method considering the running resistance and tension. Can be seen from the analysis of the above methods, the calculated results are accurate sequence does not depend on the key problems in the calculation, but in the conveyor running resistance in the process of calculation is accurate. The operation process of belt conveyor consists of start-up - stable operation - stop, although in most of the time in the stable operation of a conveyor or stop state, but the process at the start and stop will have inertia load produced by the acceleration or deceleration, and therefore need to be considered in the design of the conveyor dynamic load. Traditional design and calculation methods (such as DIN22101) are all moving parts on the conveyor as rigid connection together, at the same time accelerate or decelerate (which can be seen as a quasi static), regardless of the viscoelastic properties of conveyor belt and drive in the process of start-up, stop input force (torque) change over time, and so cannot be given conveyor in transient process in the process of start-up, stop. From the Angle of the transient process of belt conveyor, the dynamic problems in the following aspects:(1) the start of the conveyor, stop the conveyor in the process of the longitudinal stress (strain) and the speed of transmission especially large belt conveyor belt conveyor structure characteristics embodied in: conveyor belt, roller, and material is spread on the transmission line, conveyor belt is essentially a viscoelastic body, thus drive the boot process is gradually will spread to the whole conveyor belt, driving force and speed of the conveyor start is a gradual process, conveyor belt tension by static state changes to stable operation under tension, change of the amount of deformation of the conveyor belt tension, the tension device of elongation or shortening and absorbed by the deflection of conveyer belt change. Another characteristic is more drive unit and multi-points driving. When there is no considering the influence of the longitudinal dynamic transient process possible problems include:1) choose too driven equipment investment cost is too high, cause in the process of start and stop the conveyer belt tension is too large;2) changing slope line of the belt conveyor downtime caused the conveyor belt in the process of local tension is too small;3) displacement of the tension device design is not accurate, appear taut enough or pull tight schedule response lag, cannot satisfy the requirement of the system transmission;4) drive, brake and tension device configuration and location layout is unreasonable;5) in a multiple drive unit in the system to start or braking process due to the loading sequence and time control on the oscillation problem, caused by the drive unit of output cannot realize synchronization and power balance.(2) the conveyor belt on cross section perpendicular to the conveyor belt surface vibrationIntrinsic properties in tension, the load and conveyor belt conveyor belt, when the vibration frequency and inherent frequency of roller close to, or agreement, conveyor belt of the cross section in the direction of the vertical surface vibration problems, the vibration will make the conveyor frame buildings destroyed even 12-14.(3) the conveyor belt running deviation in horizontal conveyorConveyor belt running deviation is widespread problem, running deviation is conveyor downtime, and materials, frame jam, conveyor belt use shortened the main reason for the consequences, such as running wide adjustment is very troublesome, theoretically analyzing the running deviation method is to establish a dynamics equation of movement of the conveyor belt cross use, and application of the theory of stability was analyzed.(4) conveying material quantity changes caused by changes in the running stateConveying material quantity change will cause the change of running state, but the change relative to the conveyor belt is much longer, and the volatility of the cycle and generally will not separate study on this question, the research focus is on different materials under the load distribution of longitudinal wave problem.(5) materials by the process of material on the roller and the impact of the conveyor beltConveyor belt is impacted by the material in the material (especially the big materials) impact directly endanger the normal use of belt conveyor, is the important reason for the damage of conveyor belt, conveyor belt leads to wear, covering layer, core, and even the breakdown of the whole conveyor belt, cause the damage of the conveyor belt and tear, increase the impact load of roller.(6) after a roller conveyor belt conveyor belt cover extrusion deformation and recoveryConveyor belt under extrusion deformation of cover on the conveyor belt is conveyor main drag in the sag resistance. From the point of view, the control of belt conveyor in addition to meet the meet the technological requirements of belt conveyor under different throughput sequence control and the speed of change and the protection of a belt conveyor control, the control requirements of main lies only in the conveyor of the transient process control. Visible from the above analysis, the belt conveyor dynamic problems involved in all aspects of the belt conveyor system, this article focuses on the first (1) aspects of listed above, and the other five aspects of the problem only briefly discussed in this paper. First analysis of the domestic and foreign research progress and the method; , in turn, dynamics analysis is given of the basic method and process, including: the development of mathematical models, solving technology, software; Dynamics analysis of a typical belt conveyor system, function and application scope of dynamic analysis, etc.The main content and method of dynamics research Belt conveyors dynamic analysis and dynamic design method of research and application are widely attention, is because with the large-scale of belt conveyor system, traditional half