热风阀阀板的节能探讨

现有热风阀阀板承受着很大的热载荷,必须依靠强制冷却才能正常工作,相应的热损失和水泵耗电量相当可观,本文运用有限元方法对某钢铁公司的实际热风阀阀板的温度场进行了分析,探讨了节能的途径和措施,可为热风阀的节能降耗提供理论参考和依据。     

换流站阀控保护闭锁隐患分析及措施

在介绍上海南桥换流站阀控保护系统的结构与功能的基础上,解读了晶闸管电子设备、阀基电子设备和阀监控设备的作用与信息传输通道。通过深度排查隐患,梳理和分析了阀控保护的各种告警和闭锁信号,从中列出了导致直流逻辑闭锁的3条隐患。针对"ACTIVE"信号回路故障、MC板或DIO板故障、直流电源进线失电故障,制定了相应的整改措施,以确保直流输电系统安全稳定运行。     

东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆动应力分析

汽轮机主汽阀需要很高的关闭速度,由此带来阀杆冲击动力学的强度问题。以前设计主要按照冲击动力学的理论,通过能量法求解系统动应力。文章介绍了阀杆动应力的理论计算方法,并分析了理论计算方法的合理性。随着计算机技术的发展,有限元方法求解阀杆动应力成为可能。文章详细介绍了阀杆动应力有限元计算参数的选取方法,并通过ABAQUS商用有限元软件计算了东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆动应力。对理论计算结果和有限元计算结果做了比较,分析了有限元计算结果的合理性。计算显示东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆峰值应力小于材料疲劳极限,阀杆具有永久寿命。     

超超临界百万千瓦汽轮机主调阀流场非稳态数值研究

采用计算流体力学商用Fluent软件,对某百万千瓦超超临界汽轮机主调阀系统(主汽阀和调节汽阀组成的进汽系统)正常运行时的蒸汽稳态流场和快速关闭时的非稳态流场进行了全三维数值计算及分析.结果表明:稳定工作状态下,阀门全开时的阀组总压损失约为进口总压的1.23%,其中调节汽阀损失占总损失的57.52%;主汽阀、调节汽阀都为快开特性的阀,它们的相对升程大于30%时流量基本不可调.采用Fluent中的动网格技术,计算分析了调节汽阀从全开到快速关闭的非稳态过程中蒸汽的流动特性,并给出了调节汽阀快速关闭时的行程、流量及阀后压力与关闭时间的动态曲线.     

汽轮机主汽阀阀碟深孔加工

介绍了汽轮机主汽阀阀碟深孔加工方法,在数控机床进行加工,改造了数控机床原有刀架,设计制造了专用刀架、同心刀杆,提高了刀架最大装夹刀杆的厚度,加大了数控刀架移动的硬行程范围,有效地解决了主汽阀阀碟深孔加工的技术难题.     

引进300MW汽轮机主汽阀与调节阀阀壳的以铸代锻设计

一、前言从美国西屋公司(WH)引进的300MW机组的高压主汽阀与调节阀的阀壳,原设计为锻件,目前国内无法供应锻造毛胚,需要进口。引进型第一台机组的高压主汽阀与调节阀是全套向WH购买的,每台机组     

某电厂高压主汽阀阀碟锈蚀分析

用物理、化学和能谱分析方法，对某电厂高压主汽阀阀碟及其套筒的锈蚀原因进行了研究和分析。结果表明，３０Ｃｒ１Ｍｏ１Ｖ钢和３０Ｃｒ２ＭｏＶ钢的抗氧化性能相当，电厂所用热蒸汽品质不符合标准。     

浅谈采用旁通阀调节再热器汽温的方法及设计原则

介绍了在具有中间再热系统的锅炉上几种实用的调温方法，对于采用旁通阀调节再热器汽温的方法及旁通阀的设计原则进行了阐述。     

CAESAR Ⅱ软件在补汽阀管道设计中的应用

补汽阀管道是超超临界汽轮机设计中唯一需要采用高参数设计的管道,本文主要介绍了补汽阀管道的布置方法,并采用商业软件CAESAR_Ⅱ对补汽阀管系进行计算,以满足电厂布置要求。     

基于壅塞流的动力电池防爆阀泄压特性的动态仿真

防爆阀作为缓解电池系统热失控的被动安全措施,在电芯设计中扮演着非常重要的角色,防爆阀的开启压力、阀体面积及阀体位置对电芯热失控后的泄压过程有着重要影响。本工作主要介绍了动力电池热失控后产热产气导致防爆阀开启的泄压过程,通过理论计算、实验测试及仿真分析相结合的方式,对防爆阀的泄压特性进行了系统阐述与分析。首先,基于流体力学基本原理和方程从理论上对防爆阀的泄压过程进行了分析,阐述了电芯热失控过程中防爆阀开启后的泄压壅塞流基本状态;其次,通过开展无阀电芯的加热热失控和过充热失控两类实验,实验中实时监测了电芯热失控过程中卷芯的温度和电芯的内压,从而得到电芯热失控过程中防爆阀开启前电芯的产热产气速率;最后,对电芯的产热产气及泄压过程进行仿真,基于COMSOL软件,建立了动力电池防爆阀泄压过程的系统模型。且对防爆阀的开启压力、阀体面积及阀体位置等影响因素进行了归类仿真分析,并与实验数据进行了对比验证,得到了较为优化的防爆阀结构设计,为动力电池优化设计提供了一定的参考。     

4800 m^3高炉热风炉设计及运行研究

在某炼铁厂4 800 m^3高炉顶燃式热风炉的设计中,采用长寿型双预热、清洁生产等具有国内领先水平的生产技术,并结合实践对高炉热风炉热工参数、设备、耐火材料的结构等进行了分析研究,实现了高炉风温的稳定输送,满足了高炉生产的要求,取得了良好的效果.     

浅析热风炉炉顶内衬结构型式

热风炉炉顶是热风炉的关键部位,关系到热风炉一代炉龄。炉顶内衬结构是热风炉类型的重要特征,决定着热风炉炉型和炉衬寿命的长短。总结了目前热风炉炉顶内衬结构及其耐材砌筑方式,对多种炉顶结构进行了分析比较,可供高炉选择热风炉类型时参考。     

Conjugate heat transfer analysis of copper staves and sensor bars in a blast furnace for various refractory lining thickness

Lining erosion is the most important factor for determining the campaign life of a blast furnace. To provide information about the heat transfer of the copper stave in the belly of the No. 1 blast furnace at CSC (China Steel Corporation), a conjugate heat transfer model, including the heat transfer of the stave and sensor bar in thermal conduction and radiation transmission from the gas temperature inside the blast furnace and convection heat transfer in cooling pipe, was developed for the steady state process. The simulations focus specifically on the effects of the gas temperature, the geometric thickness of the cooling stave, the slag layer thickness and the material and diameter of the sensor bar. The results show that the refractory lining and the slag shell provide significant protection for the stave body. A copper sensor bar can be used to measure the residual lining thickness of the cooling stave. To estimate a more reasonable stave thickness, several key factors, such as the diameter and material of the sensor bar, were examined in this study. The results can serve as important reference information for blast furnace operation and the prediction of its campaign life.     

基于某型国六柴油机气门导管异常磨损问题的分析及改进

针对某型国六柴油机在耐久实验中出现漏气量高的问题,对整机的零部件进行拆解发现排气门导管异常磨损,通过对实验排气门外观、尺寸的分析,对排气门导管外观、材料、硬度、金相组织、磨损、内壁的扫描观察等分析,对排气门温度场实验分析,得出气门导管是因温度过高使热硬度下降,从而导致排气门与气门导管不匹配,使气门导管出现异常磨损。在此基础上提出优化水套结构,改善气门导管材料来解决这个问题,最终经过台架耐久试验验证了这一方案。     

高炉陶瓷杯炉衬技术应用

陶瓷杯炉衬是现代大型高炉长寿综合技术。鞍钢新1#高炉引进日本NDK微孔超微孔碳砖和法国SAVOIE陶瓷杯炉衬关键技术和材料,国外设计、耐火材料供应、工程监理;国内招标,中标承建施工。炉衬结构、耐火材料及其砌筑方式值得国内高炉借鉴。消化、移植、创新开发具有中国特色的高炉长寿炉衬技术。     

电厂阀门内漏在线监测研究

减少阀门内漏量是电厂重要的节能减耗手段.对阀门内漏在线监测及其经济性分析研究,采用基于传热学原理的方法计算阀门内漏量,等效焓降法计算内漏量对于机组经济性影响.对某一电厂300 MW机组阀门的内漏量进行监测,结果表明:该系统能定量计算阀门内漏量和对电厂煤耗的影响,具有非接触、在线、实时测量等优势,可以为电厂运行人员提供阀门检修、检漏的依据和参考.     

JZ-7型空气制动机作用阀故障的原因分析与防止办法

针对我国铁路内燃、电力机车上使用的JZ-7型空气制动机中作用阀的作用与故障现象,进行了故障原因分析,并对防止作用阀发生故障提出了建议。     

Heat transfer analysis of blast furnace stave

The three-dimensional mathematical model of temperature and thermal stress field of the blast furnace stave is built. The radiation heat transmitted from solid materials (coke and ore) to inner surface of the stave, which has been neglected by other studies, is taken into account. The cast steel stave is studied and the finite element method is used to perform the computational analysis with soft ANSYS. Numerical calculations show very good agreement with the results of experiment. Heat transfer analysis is made of the effect of the cooling water velocity and temperature, the cooling channel inter-distance and diameter, the lining material, the cooling water scale, the coating layer on the external surface of the cooling water pipe as well as the gas clearance on the maximum temperature and thermal stress of the stave hot surface. It is found that reducing the water temperature and increasing the water velocity would be uneconomical. The heat transfer and hence the maximum temperature and thermal stress in the stave can be controlled by properly adjusting operating conditions of the blast furnace, such as the gas flow, cooling channel inter-distance and diameter, lining material, coating layer and gas clearance.     

EVALUATION OF THE DYNAMIC PERFORMANCE OF A HOT WATER TANK WITH BUILT-IN HEATING COIL

Hot water tanks with a built-in water-heating coil are commonly used in district heating house stations in Denmark for domestic hot water (DHW) production and storage. In this study, an evaluation of the dynamic performance of a hot water tank with built-in heating coil is carried out by applying a dynamic simulation programme which has been made previously, based on a simple dynamic model developed by the authors. System evaluation of the way in which system parameters, such as control valve size, heat loss coefficient of the DHW circulation pipe, position of the temperature sensor (for DHW temperature control) and fouling of the heating coil, affect the domestic hot water capacity and the average district heating water cooling for a given hot water tank is presented and discussed in this paper. The evaluation results show the importance of the correct design of the control valve size, the reduction of heat loss from DHW circulation pipes, the careful adjustment of temperature sensor position and temperature sensor set-point, and the reduction of the heat coil fouling growth rate in order to operate the hot water tank in an efficient way and to achieve significant cooling of the district heating water. © 1997 by John Wiley & Sons, Ltd.