共查询到18条相似文献,搜索用时 312 毫秒
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钢卷冷却过程中温度的变化对组织的形成、二次相的析出以及晶粒尺寸起着至关重要的作用,因此,获得钢卷冷却过程的温度场变化规律有重要的现实意义。计算符合实际冷却工艺的比热容及建立钢卷内表面换热系数和钢卷层与层之间热阻的模型,采用Deform-2D软件对微合金高强钢卷自然空冷过程进行数值模拟。比较模拟温降曲线与试验数据,验证了该模型的正确性,并研究分析了钢板厚度和卷取温度对钢卷冷却温度场的影响。结果表明,钢板厚度越大,钢卷温度分布越不均匀,卷取温度越高,钢卷发生相变的时间越长,但钢卷各部位冷速不会因此而改变。 相似文献
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针对镀铬钢卷内部温度分布无法准确预报而导致在厂区存放中钢卷结露锈蚀的现象,在大量理论研究与现场试验的基础上,采用钢卷三维温度模型的分析方法,通过建立导热微分方程,进而建立了一套新的钢卷冷却过程内部温度分布模型,并分析了多种环境条件下对模型的计算精度,在此基础上,编制出了"镀铬机组成品带钢冷却过程钢卷内部温度预报软件",并将其推广应用到某钢厂镀铬机组的生产实践,解决了现场镀铬钢卷结露锈蚀的缺陷问题,为厂区钢卷存放措施的制定提供了一定的理论依据与数据支撑,具有进一步推广应用的价值。 相似文献
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为控制中厚板中间坯长时间待温导致的晶粒长大,研究了中间强制水冷却对奥氏体组织的影响.通过对Q345B钢和含Nb-Ti钢采用1050℃变形后快冷至1050~950℃预定温度保温的热模拟方法,确定了中间坯冷却过程中的晶粒尺寸变化规律,提出了中厚板冷却过程中晶粒长大的控制方法,建立了Q345B钢和含Nb-Ti钢在中间冷却过程中的晶粒长大模型.在中间冷却过程中,Q345B钢晶粒稳定性较差,而含Nb-Ti钢晶粒稳定性良好,归因于以铌为主的析出相对奥氏体晶界的钉扎作用.中间坯的强制冷却可控制奥氏体晶粒长大,63mm厚中间坯强制冷却可有效减小平均晶粒尺寸约20μm.在实际生产中,经中间强制冷却后16 mm厚度Q345B钢板的冲击韧性提高25%~70%. 相似文献
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针对某厂全氢罩式炉机组在退火过程中,由于钢卷冷热点温差过大且保温时间过长而出现产品质量问题的现象,建立了该机组退火过程传热数学模型。在钢卷导热系数、对流换热系数中加入修正因子,并研究了各系数的处理方法,经过大量实测数据的修正,得到了较优的修正因子。应用有限差分法求解数学模型,以某组第3卷钢卷计算结果为例,与实测数据对比,结果表明,热点温度计算值中92%的温度点的误差为5.12%以下,冷点温度计算值中90%的温度点的误差为5.05%以下。说明本文的数学模型和计算方法可靠,可用于该厂全氢罩式炉机组退火过程中温度场的预测分析,对退火工艺制度的优化有一定指导意义。 相似文献
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WANGLi-juan ZHANGChun-li 《钢铁研究学报(英文版)》2004,11(5):37-40
The layer thermal conductivity during constraint cooling of hot rolled coil was dcscribed by using equivalent thermal conductivity model and finite element method. Two radial stress concentration zones in constraint cooled coil were shown by numerical analysis, and the tension stress was assumed to be the main factor to induce stress corrosion. The experimental results show that the longer the water cooling time is, the smaller the grain size and the more uniform the grains are. 相似文献
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《钢铁研究学报(英文版)》2011,(Z1):615-620
The effects of technological parameters on microstructures and properties of low cost hot rolled dual-phase steel was researched by design different finish rolling temperature,mid cooling temperature between laminar cooling and UFC (ultra fast cooling) and stable UFC rate on the same gauge strips with the same chemistry composition during the manufacture process.It is the key for controlling coil temperature to control finish rolling temperature and mid cooling temperature between laminar cooling and UFC that based on stable UFC rate precondition.The lower finish rolling temperature,with mid cooling temperature between laminar cooling and UFC,the better to form martensite is.The foundation of developing the similar productions on the similar product line was supplied.It is good to technological advancement of developing high affixation value production as hot rolled DP steel,TRIP steel etc.in CSP line. 相似文献
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�¼��� ������ ��ƽ�� 《钢铁研究学报》2013,25(10):14-19
In order to solve the problems of time-consuming and intense vibration during the calculation process of inverse heat conducting problem (IHCP) with conjugate gradient method (CGM), a non-iterative model was developed based on finite element method (FEM) and related program code was compiled with Fortran. This non-iterative method was then applied to IHCP of laminar cooling process of hot rolled steel plate to calculate the convective heat transfer coefficient in the boundary. Through comparison of the convective heat transfer coefficient obtained by both CGM and the non-iterative method, the results were shown to be consistent with each method. Furthermore, the computing result of the non-iterative method were more stable, and had an obviously faster speed, which eventually cut down the whole computing by 76%. The new method could retain high sparsity of the matrix, which is more concise than the exiting non-iterative method. Besides, the new non-iterative method could also be an efficient way to calculate the heat flux and wall temperature at the same time, which made it possible for real-time output of boundary conditions during laminar cooling process of hot rolled steel plate. 相似文献
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GONG Dian-yao XU Jian-zhong PENG Liang-gui WANG Guo-dong LIU Xiang-hua 《钢铁研究学报(英文版)》2007,14(4):11-14
The mathematical model for online controlling hot rolled steel cooling on run-out table (ROT for abbreviation) was analyzed, and water cooling is found to be the main cooling mode for hot rolled steel. The calculation of the drop in strip temperature by both water cooling and air cooling is summed up to obtain the change of heat transfer coefficient. It is found that the learning coefficient of heat transfer coefficient is the kernel coefficient of coiler temperature control (CTC) model tuning. To decrease the deviation between the calculated steel temperature and the measured one at coiler entrance, a laminar cooling control self-learning strategy is used. Using the data acquired in the field, the results of the self-learning model used in the field were analyzed. The analyzed results show that the self-learning function is effective. 相似文献
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带高压水除鳞换热的带钢粗轧过程温度场数值模拟 总被引:3,自引:1,他引:2
热带钢在轧制前通常需用高压水去除氧化铁皮。随着高压水对带钢表面冲击强度的增加,除鳞效果明显增强,带钢的温度也显著降低。影响带钢温度变化的因素复杂多变,其中尤以高压水的影响较显著,因此研究带钢在高压水除鳞过程中的温度场分布,对于了解带钢粗轧过程中的温度变化、合理制定后续精轧工艺非常必要。笔者将有限元数值解法与实验结果相结合,研究了高压水冲击强度与带钢换热系数之间的对应关系,得出了换热系数计算模型。将该模型应用于宝山钢铁集团公司2050mm热带钢粗轧机组进行模拟计算。结果表明模拟值与现场实测值吻合良好。 相似文献