High-speed steel rolls used for cold rolling

During cold rolled production of steel,each change of rolls causes a halt in production and affects the roll’s grinding maintenance and consumption.Consequently,rolls are very critical to the costs of steel production. Besides the rolling accidents,surface quality problems,including inhomogeneous wear and a decrease of the surface roughness of the rolls are other main reasons for outage and a change of the rolls.Therefore,safe rolls,with superior wear resistance and roughness retentivity will be a future trend in the cold rolling steel industry.In this study,the property characteristics and in-service performance of high-speed steel(HSS)cold rolling work rolls at Baosteel are discussed.The results of this study indicate that in-service performance of HSS cold work rolls has an improvement over conventional rolls.Implementation of HSS work rolls will prolong the rolling campaign and improve the rolling stability,thus,the cost of cold rolling production can be better controlled.     

冷轧机工作辊非对称弯辊的板形调控理论研究与应用

为减少冷轧带钢的非对称板形缺陷的产生,设计了工作辊非对称弯辊控制系统.应用影响函数法计算辊系变形,同时考虑辊缝中金属横向流动对带钢出口横向张力分布的影响,通过迭代法计算出工作辊两端施加不同弯辊力后的辊间压力分布、出口厚度横向分布以及出口横向张应力分布.理论分析结果表明,工作辊非对称弯辊可以在一定程度上改善辊间压力分布不均,减轻轧辊磨损和减少轧辊掉皮事故的发生,降低带钢边部的非对称板形缺陷.实际应用结果证明,当倾斜调整量小于10%时,应用工作辊非对称弯辊替代倾斜调整,可以获得更好的板形精度.     

Retained austenite in the cracking process of steel on the working rolls of the cold sheet rolling mill

It was proved that the volume fraction of retained austenite (RA) in the quenched samples of the 0.80%C, 1.80%Cr, 0.23%Mo, 0.17%V steel on the working rolls of cold sheet rolling mills depends on their sizes. During tempering of this steel at 160°C the RA is stabilized so strongly that it is transformed neither by means of stresses nor strains. It was computed that in this steel, every 1% by volume of RA increases its fracture toughness (K_lc) by about 5%. Under conditions of dynamic loading the power of effect of RA is increased to about 7%.     

Method for improving the reliability and service life of mill rolls

Translated from Metallurg, Vol. 39, No. 2, p. 38, February, 1995.     

轧机振动监测系统在冷连轧机上的应用

由于轧机设备的复杂性,轧机振动是长期困扰生产现场的疑难问题。在不改动任何现有设备和控制系统的基础上,轧机振动监测系统通过实时采集轧机的振动信息与工艺信息,可以实现轧机振动状态的实时监测,并根据所设定的报警模型对轧机振动进行报警判断。现场的实际应用效果表明,其在振动报警与减少轧机振动次数、振动纹缺陷的量化评价、轧机振动特性分析、辊系状态监测等方面均具有较好的效果,且在提振操作信心、优化用辊制度、事故原因分析、振动对比跟踪方面也有一定的效果,具有较高的推广应用价值。     

UCMW冷连轧机组各架中间辊端部辊形

针对UCMW冷带轧机板形控制中存在的两类耦合问题——边降与平坦度的控制耦合以及工作辊弯辊与中间辊弯辊的调控功效耦合,定义了描述耦合度的参数以量化其耦合程度,提出通过设计中间辊端部辊形实现对两类耦合问题的解耦思路,并以某1550UCMW冷连轧机为对象进行了中间辊端部辊形设计.仿真计算结果表明,利用所设计的中间辊端部辊形可以在一定程度上化解两类耦合问题的耦合关系,且可以进一步优化改善轧机的板形控制性能,达到提高实物板形质量的目的.