长一维直通式辊底加热炉内传热数学模型研究

通过分析ＣＳＰ工艺中直通式辊底加热炉的热工及结构特性,采用地建立炉内辐射换热数学模型,与加热炉内连铸坯及炉衬的一维导热方程相耦合,建立长一维直通式辊底加热炉炉内传数学模型,通过对数注解,研究分析了不同的薄板坯移动速度及 种对加热炉炉内温度分布的影响。     

中厚板S355钢辊底式炉正火工艺研究

为保证在S355中厚板组织性能优异的前提下缩短正火时间,降低辊底式炉能耗,提高生产效率,采用MSC.Marc软件对辊底式炉内钢板的二维温度场模型进行有限元模拟,并通过黑匣子实验验证模型的可靠性,在此基础上,以该模型对辊底式炉的正火工艺进行优化实验。结果表明,升温时间为0.95{H}min（H为钢板厚度,mm）、保温时间为0.8{H}min时,中厚板的各项性能满足要求,且加热时间缩短了28.6%,达到了节能减排的目的。     

辊底炉炉辊改进前后的热损分析和控制优化

采用数学模型分析辊底炉炉辊改进前后的水冷合金辊、纤维辊的热损规律．分析辊底炉存在的问题,指出炉辊改进的原因和关键点;建立两种炉辊的传热模型,提出基于牛顿搜索的迭代规划求解算法;研究冷却水流速和进水温度与两种炉辊截面上不同材质界面处的温度、出水温度、温升、吸热量及换热系数的关系．结果表明:炉辊分界面温度、出水温度、冷却水温升随流速增加而减小,两种辊临界流速为0.07和0.09 m／s,大于临界流速发生湍流,冷却效果倍增;考虑到减少结垢和水系统造价,还应控制出水温度在45 ℃之下和温升小于10 ℃,合适流速为0.4～0.8 m／s和0.2～0.6 m／s,此时完全湍流,冷却效率高,温升小;再增大流速,冷却水吸热量变化不大,能耗增大;强制湍流换热时,纤维辊热损约为合金辊的78％．应用效果表明:炉辊改进及优化控制后,由于纤维炉辊热损小,并且不用磨辊,产量大大提高,吨钢燃料消耗量大幅降低．     

蓄热式加热炉分布式测控系统

加热炉是热连轧生产线重要设备,近年来基于现场总线分布式测控系统在连续轧钢生产线中应用越来越多,郑州热轧带钢厂加热炉采用现代蓄热燃烧技术的蓄热式加热炉,本文介绍其基于profibus现场总线分布式测控系统的硬件构成和软件功能,重点讨论加热炉回路控制方案和故障连锁分析应用软件实现方法。     

锻造余热退火辊底炉研制

简要介绍了锻造余热退火辊底炉生产线的组成,着重讨论了炉子的结构特点.该辊底炉主要用作GCr15轴承套圈热镦成型后的余热球化退火,炉子具有结构紧凑、节能、自动化程度高和使用安全可靠等特点.     

台车式加热炉Fuzzy-PID复合控制系统

为了解决台车式加热炉运行过程中使用传统方式进行温度、压力及流量控制表现出的低效率、误差大、能耗高等问题,提出设计与开发台车式加热炉Fuzzy-PID复合控制系统.文中首先介绍了台车式加热炉控制工艺模型,它由多个空燃气支管混合燃烧的温区组成;进而叙述了传统PID控制算法与单一Fuzzy控制算法的内容与原理;最后对Fuzzy-PID复合控制器的理论结构与硬件模块结构进行了详细地论述.通过实验表明,台车式加热炉中使用Fuzzy-PID复合控制方式可以扬长避短,具有调节精度高、鲁棒性强,控制稳定性好等优点.     

蓄热式加热炉的神经网络燃烧控制

蓄热式加热炉温度对象具有非线性、大滞后的特点,本文运用神经网络的控制方法,在被控对象进行在线辨识的基础上,对神经网络权系数进行实时调整,使系统具有自学习、自适应性,仿真效果表明其控制效果优于一般PID控制。     

蓄热式加热炉燃烧控制算法研究及应用

蓄热式加热炉是通过蓄热室热交换的高温空气燃烧技术,利用纯高炉煤气为燃料,具有高效烟气余热回收、低污染排放等优点,在工业生产中应用越来越广泛。由于蓄热式加热炉采用左右两侧空气、煤气交替切换燃烧,在切换期间其温度对象处于非控状态,切换周期为3—5min,常规的双交叉限幅燃烧控制策略巳不再适用。本文运用神经网络方法在线建立当前工况下温度控制平衡工作点,在此基础上通过模糊控制策略实现蓄热式加热炉温度控制,实际应用结果表明这种控制策略有效解决了蓄热式加热炉切换燃烧控制问题。     

蓄热燃烧技术在马钢重机台车式加热炉上的应用分析

对蓄热燃烧技术在马钢重机锻钢线台车式加热炉上的应用进行了探讨,提供了几种蓄热式台车加热炉的应用形式并进行了分析,重点是目前应用中普遍存在的问题,同时提出了一些优化设计建议.     

平炉钢渣配制水泥的研究

分析了钢渣的组成，介绍了钢渣利用的可能途径，提出了用平炉钢渣作为普通硅酸盐水泥水硬性混合材综合利用的方案．     

Effects of Ti addition on low carbon hot strips produced by CSP process

Large quantity of fine Ti（C,N） particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti（C,N） mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride particles could be very effective on the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.     

Numerical simulation for the lower shaft and the hearth bottom of blast furnace

One of the methods forming the shell is to appropriately design the cooling staves and hearth without overheating during the campaign life of the furnace. The three-dimensional steady mathematical models for calculating the temperature distribution in the coolers and two-dimensional unsteady mathematical models with phase-change latent heat for calculating the temperature distribution of the hearth bottom were established. The calculation results show that the formation of the slag-metal protection shell can be achieved by optimizing the design parameters of the coolers. Increasing the heat conductivity of the carbon brick can move the isothermal line of 1150℃ upward outside the hearth bottom.     

Precipitation characteristic of high strength steels microalloyed with titanium produced by compact strip production

Transmission electron microscopy (TEM) and physics-chemical phase analysis were employed to investigate the precipitates in high strength steels microalloyed with Ti produced by compact strip production (CSP). It was seen that precipitates in Ti microalloyed steels mainly included TiN, Ti4C2S2, and TiC. The size of TiN particles varied from 50 to 500 nm, and they could precipitate during or before soaking. The Ti4C2S2 with the size of 40-100 nm might precipitate before rolling, and the TiC particles with the size of 5-50 nm precipitated heterogeneously. High Ti content would lead to the presence of bigger TiC particles that precipitated in austenite, and by contrast, TiC particles that precipitated in ferrite and the transformation of austenite to ferrite was smaller. They were less than 30 nm and mainly responsible for precipitate strengthening. It should be noted that the TiC particles in higher Ti content were generally smaller than those in the steel with a lower Ti content.     

工业型煤炉前成型机的设计及性能

随着国民经济的发展,对工业锅炉高效,低污染燃烧的要求越来越高,而工业锅炉燃用型煤具有良好的环境效益和节能效益,与直接烧原煤相比,锅炉热效率提高５％￣１０％,排烟含尘浓度下降５０％￣６０％;固硫率（加固硫剂）４０％￣５０％,林格曼烟度〈０．５￣１．０。     

Comparison and analysis of dislocation density, morphology and evolution in microstructure of low-carbon steel produced using different technologies

Three kinds of specimens were produced from hot strips of similar composition and same thickness （nominal gauge 4.0 mm） but produced using different technologies, and the dislocation density of these strips was quantitatively measured by positron annihilation technique test. The dislocation morphology and evolution in microstructure of each pass for producing the 1.9 mm hot strip using CSP （compact strip production） technology were observed under an H-800 transmission electron microscope; its density was also quantitatively measured using the positron annihilation technique test, and the factors influencing the dislocation density during the production process were analyzed. The experimental results show that the dislocation density in the microstructure produced using CSP technology is higher than that in the microstructure produced using conventional technology. This result was discussed and confirmed on the basis of the finite element simulation and the theory relevant to dislocations.     

数字脉冲燃烧控制技术在锻钢退火炉中的应用

阐述了数字脉冲燃烧控制技术的控制原理,提出了利用单纯型法寻优燃烧周期控制炉膛温度,给出了燃烧方式软件控制优化锻钢退火工艺。通过现场应用结果对比,该控制技术比传统控制技术在炉温控制中控制精度高,动态性能优越,节能约8%。     

高炉炉底侵蚀线的计算

针对梅山３＾＃高炉炉底条件,用有限元素法开发了只依靠热遇测得的湿度作为边界条件和修正温度,对炉底侵蚀情况进行在线监测的二维数学模型,解决了采用炉底及炉侧的对流边界条件以实时检测的问题。模型中采用网格变形拟合的方法处理边界移动的问题,算法简单便于在线运行。通过梅山３＾＃高炉的实际应用及对不同侵蚀状态的计算,结果是令人满意的。     

攀钢热轧加热炉自动燃烧控制系统的周期计算

介绍了在攀钢1450热轧板厂两座265 t/h的步进梁式加热炉上开发应用的L1,L2两级燃烧控制系统,其中,L1级燃烧自动控制系统主要实现如何以最快的响应速度完成以温度为目标的燃烧控制;L2级燃烧自动控制技术,主要实现在线情况下,考虑不同钢坯材质、规格、不同轧制规格、不同的组织计划、不同的钢坯装入温度、不同的生产节奏下(与轧线一体控制的)的燃烧温度的设定模型技术,以数学手段计算出在各种因素影响下,加热炉各个控制段的最佳加热温度。重点阐述了加热炉自动燃烧控制模型的核心———ACC模型周期计算处理的方法。