电厂风机的应用及故障分析.doc

电厂风机的应用及故障分析

摘    要
机械故障诊断是上世纪六七十年底产生并发展起来的一门综合性边缘学科。随着科学技术的不断发展，生产设备越来越复杂，自动化水平越来越高，故障诊断的难度明显增大。因此，研究和开发高效、使用的机械故障诊断技术，不仅是现代化生产及设备制造自动化的需要，也是现代机械设备运行维护和管理的一个课题。
风机是一种从动的流体机械，广泛应用于隧道、地下车库、高级民用建筑、冶金、厂矿、电厂等场所的通风换气及消防高温排烟。风机的工作是以输出流量，产生全压、所需功率及效率等参数来体现的，这些工作参数之间存在着相应的关系。在发电厂中，需要许多风机同时配合主机工作，才能使整个机组正常运转、生产电能，这些风机有离心式、轴流式、混流式等多种形式，风机输送的流体有凝结水、冷却水、润滑油、酸碱类等液体，空气、烟气等气体。送风机、引风机使火力发电厂中的重要辅助设备，它们对于火力发电厂的安全、经济生产起着重要的作用。风机在发电厂的热力系统中，如人体的心脏一样，不断地在循环系统中工作，同时，近年来大容量火力发电机组在我国迅速发展，大型电站风机的可靠性直接关系到发电机组的安全运行和电厂的经济效益等。
   本课题在现有风机性能试验台的基础上，利用电子技术、计算机技术、数据处理技术及组态软件技术向结合，研究并设计了一套计算机辅助风机性能自动测试与数据处理及管理系统。
   风机刚开始工作时轴承部位的振动很小，但是随着运转时间的加长，风机内粉尘会不均匀的附着在叶轮上，逐渐破坏风机的动平衡，使轴承振动逐渐加大，一旦振动达到风机允许的最大值11mm/s时（用振幅值表示的最大允许值如下），风机必须停机修理（清除粉尘堆积，重做动平衡）。因为这时已是非常危险的，用户千万不可强行使用。在风机振动接近危险值时，有测振仪表的会报警。
关键词：风机；流体机械；机械故障诊断

Abstract
Mechanical fault diagnosis is the last century at the end of sixty or seventy the establishment and development of a comprehensive interdisciplinary. With the development of science and technology, the production equipment is more and more complex, more and more high level of automation, fault diagnosis significantly increases the difficulty. Therefore, the research and development of high efficiency, the use of the mechanical fault diagnosis technology, is not only the modernization of production equipment manufacturing and automation needs, is also the modern mechanical equipment maintenance and management of a project.
The fan is a follower of fluid machinery, widely used in tunnels, underground garage, senior civil construction, metallurgy, mining, power plants and other places of ventilation and fire of high temperature flue gas. The working air fan is to output flow, total pressure, the required power and efficiency of parameter to reflect, these parameters corresponding relationship exists between. In the power plant, need a lot of fans at the same time with the main work, in order to make the normal operation of the machine set, the production of electric energy, the fan is centrifugal, axial flow, mixed flow type and so on many kinds of forms, fan for conveying a fluid has condensed water, cooling water, oil, acid and other liquid, air, flue gas. Fan, fan so that the thermal power plant the important auxiliary equipment of thermal power plant, the safety, economic production plays an important role in. Fan in power plant thermodynamic system, such as the human body heart, constantly in the circulation system, at the same time, in recent years, large capacity fossil power unit develops rapidly in China, large power wind turbine reliability directly related to the safe operation of generating set and electric power plant economic benefits.
The issue of the existing fan performance test bed based on, use of electronic technology, computer technology, data processing technology and configuration software technology to combine, study and design a set of computer auxiliary ventilator performance automatic testing and data processing and management system.
Fan at the beginning of work part of bearing vibration is small, but as the running time longer, fan dust will not even attached to the impeller, the gradual destruction of fan dynamic balance, so that the bearing vibration increase gradually, once the vibration to fan the maximum allowed11mm/s ( amplitude value representation the maximum allowable values below), the wind turbine must be shut down repair ( removal of dust accumulation, redo dynamic balance ). Because it was very dangerous, users should never be forced to use. In fan vibration approaches the dangerous value, measuring instrument with alarm.
Key words: wind turbine; fluid machinery; machinery fault diagnosis
 
目    录
摘    要 I
引    言 1
1热力发电厂的设备及其发电原理 2
1.1热力发电厂主要设备 2
1.2热电厂发电原理 3
1.2.1汽水系统 3
1.2.2燃烧系统 3
1.2.3 发电系统 4
2风机在电厂中的应用 5
2.1风机的分类 5
2.2离心式风机和轴流式风机 6
2.2.1离心式风机 6
2.2.2轴流式风机 7
2.2.3离心式风机和轴流式风机的比较 8
2.3送风机的作用 8
2.4送风机的结构 9
2.5风机在电厂中的应用 9
3风机的性能、结构及其工作原理 10
3.1风机的性能 10
3.1.1风机在电厂中的应用 11
3.1.2风机的测试参数的选定 11
3.1.3曲线拟合 11
3.2风机的结构 12
3.3电厂风机的工作原理 13
4电厂风机的日常维护与保养 14
4.1叶轮的维护与保养 14
4.2机壳与进气室维修 14
4.3轴承部的维护保养 14
4.4风机的维护 14
5电厂风机常见的故障分析 16
5.1风机的主要故障原因 16
5.1.1风机的主要故障 16
5.1.2风机的故障排除 20
5.2风机振动故障原因分析 23
5.3电厂风机常见故障 24
5.4电场风机喘振的条件 25
5.5电厂风机的调试 25
5.6风机的安装 25
5.6.1安装前的准备 25
5.6.2注意事项 26
6电厂风机的节能改造 27
结    论 29
致    谢 31