连铸小方坯远程热送热装过程温降计算模型

建立了多块小方坯温降分块计算模型,采用有限元法计算小方坯在远程热送热装过程中内部温度及表面温度变化,得到热送热装过程的温度变化规律,为提高热送温度及制定加热炉加热制度提供了依据。     

连铸小方坯热送热装工艺实践

新余钢铁有限责任公司小方坯热送热装工艺经过两个多月的实践证明,该方案投资少,工艺合理,热送热装率为７０％,热装温度达到６００℃以上。     

重钢小方坯热送热装试验初探

本文介绍了重钢公司进行小方坯热送热装的情况。结果表明，热送热装铸坯的入炉温度平均大约450℃，取得了比较明显的效果。     

邢钢连铸小方坯热送热装工艺实践

介绍了邢钢连帮小方坯热关热装的工艺实践,建立了一系列有效的措施。经过三个月的实践证明,该方案工艺合理,投资少。热送热装率为６０％,热装温度达到６００℃。     

连铸坯热送热装的实践

本文简要介绍了不停产改造，实现小方坯远距离热送热装的技术方案及应用效果。     

浅谈如何实现特殊钢小方坯热送热装工艺

本文结合我国近年来特殊钢的发展情况以及国内外实现热送热装工艺和直接轧制工艺的实践，分析讨论了特殊钢小方坯实现热送热装工艺的特殊性，并提出了实现该工艺的设计思路及要考虑的几个条件。     

热送热装过程大板坯传热数值模拟研究

对热送热装过程中典型的大板坯温度变化建立了数学模型并分析了计算结果.研究表明:辊道输送过程热送温度对铸坯冷却速率影响较小;保温坑内堆垛的铸坯温度分布较均匀,冷却速率较慢,在8.3～9.0 K/h之间;堆垛空冷铸坯的主要冷却速率为11.3～18.6 K/h;在加热过程热装温度不同可使铸坯内外形成不同的热履历.对不同热送热装工艺过程中铸坯的温度变化规律进行了模拟,为优化界面技术提供了依据.     

连铸坯热送热装工艺的优化及效果

结合韶钢炼轧厂的生产实际，简要介绍了连铸小方坯热送热装工艺的技术方案、工艺优化措施及应用效果。     

攀钢连铸板坯热送热装及相关工艺研究

针对攀钢连铸板坯热送热装生产现状，开发了板坯热送，加热过程数学模型，进行了铸坯生产组织方式及表面质量状况轧制前后对应关系的工业试验，在此基础上，建立了铸坯热送热装管理办法和加热炉操作规程。生产统计表明，铸坯热送热装率从１９９５年的１６．７％提高到１９９６年的３６．９％平均入炉温度达５６５℃。     

国内外连铸板坯热送热装发展态势及对策

简介了国内外连铸板坯热送热装的发展态势及节能效果,提出了提高热装温度及热装率的具体措施.     

拉丝用钢连铸坯热送热装工艺实践

研究分析了拉丝用钢连铸坯热送热装过程中出现的装炉温度波动大，热坯与冷坯混装等对线材拉拔性能的影响，通过采取无缺陷连铸坯生产、控制连铸坯周围时间等工艺措施，完全能够生产出拉拔性能良好、满用户要求的优质拉拔用钢盘条，经济效益显著。     

Influence of hot working on internal cracks in continuously-cast steel billets

Continuously cast billet sections containing halfway cracks and in-plant, hot rolled rod from the same heat have been examined for open defects. It was found that significant open defects were present in the steel after a reduction of 4:1. A direct correlation between initial crack dimensions and open defects after a given reduction could not be made as the initial crack configuration varied appreciably along the billet length. Laborav scale, hot rolling of small continuously cast billet sections containing a known halfway crack configuration showed hot reductions greater than 6:1 are necessary to effectively close halfway cracks. This is applicable for cracks oriented both parallel and prependicular to the rolling plane. Small pores and lines of inclusions present in material reduced 10:1 did not affect the low temperature fracture stress of the steel.     

长钢连轧厂连铸坯热送热装工艺及实践

简单介绍了连轧厂连铸坯热送热装的设计内容,以及保证实现该工艺所采取的管理措施及实施效果。     

Heat Transfer and Central Segregation of Continuously Cast High Carbon Steel Billet

A numerical model of heat transfer was developed to investigate the heat transfer of continuously cast billet with the aid of surface temperature tests by ThermaCAMTM researcher and nail shooting experiments. The effects of secondary cooling practice and casting speed on the solidification process and central segregation of carbon were investigated as well with the actual central segregation tests. The results show that the surface center and billet center temperatures exhibit a different pattern during solidification, and the solidified shell thickness is presented as an ＂S＂ type. With the increase of secondary cooling intensity and the decrease of casting speed, the end points of the solidus line and the liquidus line move forward, and the central segregation level of carbon decreases. The optimal casting condition is suggested for continuously cast high carbon billet with F-EMS （final electromagnetic stirring）.     

提高1#连铸机至二棒轧线方坯热送率的工艺实践

通过对炼、轧钢工序开展工艺、设备、参数优化、生产组织等攻关工作,将连铸坯矫直温度提高到了1070℃以上,减少了铸坯在运输过程中的热损失,确保了铸坯进入加热炉时的温度达到850℃,综合铸坯热送热装率平均达到了64.4%,最高达到了80%的设定目标,使吨钢煤气用量得到降低,取得了一定的效果。     

Numerical Simulation and Experimental Study of F-EMS for Continuously Cast Billet of High Carbon Steel

A final electromagnetic stirring model was developed for billet continuous casting of high carbon steel using the commercial software ANSYS and CFX, and the numerical model was validated by the magnetic flux density measured under a Teslameter CT-3. The magnetic flux density and fluid flow in the liquid pool at the location of final electromagnetic stirring (F-EMS) were calculated by the present numerical model. Meanwhile, the plant trials were carried out to determine the optimum current intensity and frequency of F-EMS for the continuously cast billet of high carbon steel. The numerical results show that, through increasing the current intensity by 100 A, the corresponding increases of magnetic induction intensity, tangential electromagnetic force and flow velocity at the solid/liquid interface in the strand are 0.025 T, 1933 N/m³ and 6.9 cm/s, respectively. Moreover, the industrial trial results showed that for the continuously cast billet of 60 steel, the optimum current intensity and frequency of F-EMS, which is 8.2 m from the meniscus, are respectively 380 A and 6 Hz. With the optimum F-EMS parameters, the significant improvement of center segregation of billet is achieved, and the center carbon segregation index in billet reaches 1.04.     

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A 2D temperature model was proposed for heating rules and real-time calculation during heating process on billet reheating furnace, which included furnace temperature calculation along furnace length, billet surface fluxes calculation and conduction calculation inside billet. First, furnace temperature was accomplished according to thermocouple. Then fluxes on the above and below surfaces were calculated by total heat exchange factor method, as well as lateral fluxes. ADI and TDMA algorithms were adopted to calculate billet internal temperature distribution. Validation was carried out by thermocouple experiments and a model system was established in a hot rolling plant to provide appropriate heating rules and real-time temperature prediction. It shows precision and responsibility during reheating furnace production.     

高压气瓶钢34Mn2V 200 mm×200 mm轧坯角部拉裂缺陷的控制工艺

通过工艺对比分析了34Mn2V高压气瓶用钢中间包浇铸温度、结晶器液面波动、[Als]、中问包炉次和280 mm×380 mm连铸坯拉速波动对轧坯角部拉裂的影响。提出减小RH加Al量,按[Als]0.01%控制;RH后喂Ca-Si线;适当提高连铸钢液温度,控制中间包钢水温度1 520～1 530℃;控制浇铸过程塞棒吹氩量≤10 L/min;结晶器液位波动±3 mm等工艺措施。应用结果表明,轧坯角部拉裂缺陷率由原来的23.57%降至1.21%。     

Reasonable Temperature Schedules for Cold or Hot Charging of Continuously Cast Steel Slabs

Some continuously cast steel slabs are sensitive to transverse fracture problems during transportation or handling away from their storage state, while some steel slabs are sensitive to surface transverse cracks during the following rolling process in a certain hot charging temperature range. It is revealed that the investigated steel slabs with high fracture tendency under room cooling condition always contain pearlite transformation delayed elements, which lead to the internal brittle bainitic structure formation, while some microalloyed steels exhibit high surface crack susceptibility to hot charging temperatures due to carbonitride precipitation. According to the calculated internal cooling rates and CCT diagrams, the slabs with high fracture tendency during cold charging should be slowly cooled after cutting to length from hot strand or charged to the reheating furnace directly above their bainite formation temperatures. Based on a thermodynamic calculation for carbonitride precipitation in austenite, the sensitive hot charging temperature range of related steels was revealed for the determination of reasonable temperature schedules.     

Temperature Holding Hood for Hot Charging of Continuous Casting Slab in Tangshan Iron and Steel Company

To improve the charging of high-temperature billets, it is crucial to produce them with zero defects and achieve effective insulation during their hot delivery. A mathematical model was developed based on the heat transfer characteristics of the billet during its hot delivery. The accuracy of the model was established by studying the thermal performance of the cover of the roller conveyer for small billets in Tangshan Iron and Steel Company. The results show that the cover of the roller conveyer of the continuous casting billet can effectively reduce the heat loss during the hot delivery of the billets, and the hot loading temperature was increased by 51.6 °C. The uniformity of the temperature of the casting billet section increased substantially. The temperature difference in the casting billet section was reduced by 120 °C. The heat preservation effects of temperature holding hoods of different materials were compared. It was found that the material of the temperature holding hood has slight effect on the heat preservation.