真空热处理技术的新近进展及其发展趋势

近年来，国内外真空热处理设备和技术在迅速发展。国内研发了WZDGQ30型单室高压气淬真空炉、WZGQ型对流加热高压气淬真空炉和WZLQH型铝钎焊真空炉；国外研发了燃气真空炉，半连续和连续式真空炉，流态化真空炉，多用途真空炉，高温超高压真空炉，真空烧结炉和真空炉生产线等。本文简单介绍了上述设备，并提出了真空热处理技术的发展趋势。     

车轴件热处理与加热炉设计要求

概述了铁道机车车辆用车轴的要求和热处理工艺方法,对现行使用车轴热处理加热炉进行了对比分析,对使用较多的传送链式连续炉生产线从炉型、加热元件、传送装置自动控制和冷却室结构等进行分析,并提出了满足使用要求的设计要点和改进思路。     

三维非线性有限元在热处理炉CAD中的应用研究

提出了一个描述热处理炉三维瞬态非线性温度场的有限元模型，该模型综合考虑了辐射，处理热物性参数的边界条件等复杂因素，根据此模型，使用大型非线性有限元软件MARC，对72kW井式渗氮炉温度场进行模拟计算，模拟结果与实测结果吻合较好，由此提供了一种良好的热处理炉虚拟生产手段，可以作为知识热处理CAD的核心技术之一。     

微机在热处理炉改造中的应用

采用微机技术对旧热处理炉进行改造,使炉衬材料轻质或超轻质化,是提高热处理炉节能的最有效途径。     

真空热处理炉传热的三维数值模拟

为了分析真空热处理炉内加热工件的温度场,将包括工件在内的整个真空热处理炉作为模拟对象建立了一个三维的数值模型.该模型集成了一个控制炉温的PID模块,并且考虑了热物性参数的非线性因素.基于一商业软件,对工件、真空热处理炉的隔热层、加热管等的瞬态传热过程进行了数值模拟,并与实测值进行了对比,两者基本吻合.最后,根据模拟结果提出了优化的加热工艺参数.     

自制煤气发生炉在铸钢件热处理炉上的使用

叙述了自制煤气发生炉在铸钢件热处理炉上的使用情况，总结出了详细的操作经验，说明通过合理的操作和热风供氧，该炉的使用效果与其他工业炉比较，具有节能、高效、环保的优点。     

QP钢汽车板热处理工艺与设备探讨

通过对第3代超高强钢QP钢连续热处理工艺原理的分析，指出目前的带钢连续退火炉不能完全满足生产现代汽车板的需要，必须对其进行改进；在研究QP钢热处理工艺流程、生产的关键工艺要点、两步法工艺路线的基础上，对现代汽车板连续镀锌线、镀锌和冷轧两用线热工炉设计的要领进行了探讨，提出了典型的工艺流程布局设计方案，并分别说明了加热段、保温段、缓冷段、快冷段应有的技术要求，特别是对各钢种在过时效段所发生的转变进行了分析，阐明了新型热工炉过时效段的结构和技术要求。     

Inverse optimal design of the radiant heating in materials processing and manufacturing

Combined convective, conductive, and radiative heat transfer is analyzed during heating of a continuously moving load in the industrial radiant oven. A transient, quasi-three-dimensional model of heat transfer between a continuous load of parts moving inside an oven on a conveyor belt at a constant speed and an array of radiant heaters/burners placed inside the furnace enclosure is developed. The model accounts for radiative exchange between the heaters and the load, heat conduction in the load, and convective heat transfer between the moving load and oven environment. The thermal model developed has been used to construct a general framework for an inverse optimal design of an industrial oven as an example. In particular, the procedure based on the Levenberg-Marquardt nonlinear least squares optimization algorithm has been developed to obtain the optimal temperatures of the heaters/burners that need to be specified to achieve a prescribed temperature distribution of the surface of a load. The results of calculations for several sample cases are reported to illustrate the capabilities of the procedure developed for the optimal inverse design of an industrial radiant oven.     

Mathematical Modeling of Pottery Production in Different Industrial Furnaces

The traditional process for pottery production was analyzed in this work by developing a fundamental mathematical model that simulates the operation of rustic pottery furnaces as employed by natives of villages in Michoacán, Mexico. The model describes radiative heat transfer and fluid flow promoted by natural convection, phenomena that determine the operation of these furnaces. An advanced radiation model called the “Discrete Ordinates Model” was implemented within a commercial computational fluid dynamics software. Process analysis was performed to determine the effect of the design variables on the quality of the pottery pieces and on energy efficiency. The variables explored were: (a) Geometric aspect ratio between diameter and height of the furnace (D/H) and (b) Refractory thickness (L). The model was validated using experimental temperature measurements from furnaces located in Santa Fe and Capula, Mexico. Good agreement was obtained between experimental and numerically calculated thermal histories. It was found that furnaces with high aspect ratio D/H and with thick refractory bricks promote thermal uniformity and energy savings. In general, any parameter that increases the conductive thermal resistance of the wall furnace isolates better, and helps energy savings. Operating conditions that provide the smallest thermal gradients and lowest energy consumption are given.     

燃气式真空热处理炉技术研究开发及应用

本文概论述了燃气式真空炉技术的发展概况，重点阐述了燃气式真空炉的主要炉型，结构及特点，以及蓄热式辐射管燃气真空炉技术的特点，HTAC烧嘴结构，炉内温度分布，热平衡计算和NOx特性等，同时简介了电炉和燃气真空炉的技术经济效益比较，并对我国高温空气燃烧技术和天然气燃气处理技术设备的研究开发和推广应用进行了探讨。     

A thermal system model for a radiant-tube continuous reheating furnace

A thermal system mathematical model developed for a gas-fired radiant-tube continuous reheating furnace is discussed. The mathematical model of the furnace integrates submodels for combustion and heat transfer within the radiant tube with models for the furnace enclosure. The transport processes occurring in the radiant tube are treated using a one-dimensional scheme, and the radiation exchange between the load, the radiant-tube surfaces, and the furnace refractories are analyzed using the radiosity method. The continuous furnace operation is simulated under steady-state conditions. Model simulations of load surface temperature variation compare well with measurements in an industrial galvannealing furnace. The scope and flexibility of the model are assessed by performing extensive parametric studies using furnace geometry, material properties, and operating conditions as input parameters in the model and predicting the thermal performance of the furnace. The various parameters studied include the effects of load and refractory emissivities, load velocities, properties of the stock material, and variations in the radiant-tube designs.     

挤压铝棒坯燃油加热炉的结构和节能效果

随着技术的进步,燃油加热炉已完全能满足挤压铝棒坯的加热要求,本文对铝棒坯油加热 几种结构型式,燃烧装置,炉衬材料,烟道口和火道口的设备及温度控制系统等作了简要介绍和比较,可供设备和选炉型时参考。     

宽厚板坯连铸结晶器的热流密度与热分析

基于热电偶所实测的温度,构建了邯钢宽厚板坯连铸结晶器的有限元传热模型与其热流密度的非线性估算模型。采取模型反算的结果得出铜板的热流密度,在与热平衡方法计算出的平均热流密度做对比后,论证了模型的有效性,确定了铜板宽面、窄面的热流密度公式,分析了铜板的温度分布。铜板热面的温度曲线呈波浪状分布,其温度变化较为平缓;在靠近冷面侧的温度有最大29.4 ℃的温差。随至弯月面的距离的增大,铜板的温度减小,而在结晶器出口区域出现回温现象,大致回升23 ℃。     

工业窑炉中几种炉衬耐火材料结构的传热分析

以1250 ℃轧钢加热炉和1600 ℃隧道窑2种典型的连续热工窑炉为例,通过对不同炉衬耐火材料结构组合的综合传热系数、热流密度和炉墙温度场的传热学计算,结合耐火纤维、耐火浇注料、轻质耐火砖、Al_3O_2空心球砖及镁砖等炉衬材料的几种炉衬结构的传热分析,给出了相应窑衬结构的热导率改变对热流密度和炉墙外壁温度的影响,表明采用轻质绝热耐火材料和耐火纤维的复合窑衬结构其炉墙热流密度大大降低.计算结果显示体现工业窑炉炉衬耐火节能一体化优势的窑衬结构为:1250 ℃轧钢加热炉采用105 mm纤维板+230 mm JM23绝热保温砖+115 mm轻质莫来石耐火砖的窑衬结构;1600 ℃隧道窑采用110 mm纤维板+115 mm JM23绝热保温砖+115 mm轻质莫来石耐火砖+160 mm Al_3O_2空心球砖的窑衬结构.     

辊底式热处理炉的改造

原江西新钢钢管有限责任公司的2座辊底式热处理炉,由于是采用人工手动调节煤气流量来控制温度,由此导致钢管热处理质量不稳定,加之冷料入炉,加热时间长、出炉烟气温度高,需进行改造。通过对炉型结构、燃烧系统及炉温控制系统3个方面的改造,达到了提高炉子产量、产品质量及节能降耗的效果。     

工业炉烟气的余热利用

针对目前钢管行业工业炉尾气余热利用不足的状况,设计了一种“工业炉炉尾废气利用装置”替代空气换热器,将传统的换热介质——空气改变为水,产生的水蒸气供生产使用。从而既满足钢管生产的需要,又节约能源创造效益,同时减少环境污染。     

The Use of ''''In Process'''' Monitoring Equipment in Heat Treatment Today

HIGH VOLUME PRODUCTION in heat treatmentfacilities today lends itself to continuous heat treatmenttechniques.Gear shafts,axles,steel coils,and manyother products are heat treated in continuous pusher orroller hearth furnaces or semi-continuous low pressurecarburizing furnaces,where the products travel throughthe furnace in product baskets.Temperatures in thezones of these furnaces are carefully controlled toimpart the correct properties to the finished product,and a quench and secondary…     

圆坯连铸结晶器传热的反算法

基于圆坯连铸结晶器实测温度数据,建立了结晶器传热反问题数学模型,通过确定结晶器和铸坯之间局部热阻大小及其分布,计算出结晶器热流场和坯壳厚度,且分析了结晶器热流分布特征和铸坯凝固状态,并比较两者之间的关系．计算结果准确地反映了实际生产过程中沿结晶器周向非均匀传热特征,为将数值模拟技术应用于连铸凝固过程监控和“可视化结晶器”技术提供了可借鉴的实用方法.     

紧凑式辊底连续热处理炉计算机优化控制

以钢坯二维传热过程数学模型为基础,开发了紧凑式宽厚板辊底式连续热处理炉计算机优化控制系统。其功能主要包括：钢坯物料跟踪、钢坯温度跟踪、钢坯优化加热控制、钢坯连续及摆动运行控制、钢坯混装炉温优化控制、钢坯温度反馈控制等。采用PCS7控制系统在轧钢厂实现了辊底式热处理炉钢坯生产过程的在线优化控制和管理。经现场实际生产检验,系统运行稳定,模型准确可靠,温度跟踪最大误差1．47％,炉温优化设定值满足热处理工艺要求,热处理钢坯合格率达到98％以上。     

A mixture of pure gases that produce maximum heat transfer characteristics for quenching

Gas quenching provides a desirable alternative to conventional liquid quenching in heat treating from the standpoint of quality, safety, and environmental issues. There is convincing evidence that gasquenched parts heat treated in vacuum furnaces are clean and bright and do not require a postcleaning process that may result in additional production costs. The cooling rates for thicker section parts that are heat treated may be increased by increasing the magnitude of the heat transfer coefficient of the gaseous medium. This heat transfer coefficient, which is dependent on the thermal conductivity, viscosity, specific heat, and density of gases can be maximized by utilizing gas mixtures instead of pure gases. Substantial increases in heat transfer rates for the gas quenching process can be achieved by appropriately mixing gases such as helium and argon.