立式连续退火炉内带钢临界屈曲应力影响因素分析

Influence Factor Analysis on Critical Buckling Stress of Strip in a Vertical Continuous Annealing Furnace

在立式连续退火炉内带钢张力控制是保证机组稳定运行的重要手段,当机组炉温制度改变或带钢规格切换时,带钢张力会发生变化,如果操作不当很容易出现带钢屈曲甚至断裂,严重影响了机组的安全运行。借助有限元分析软件Marc建立了带钢临界屈曲应力模型,通过模型计算结果分析了带钢规格、带钢温度以及炉辊辊形对带钢临界屈曲应力的影响。研究结果表明:带钢临界屈曲应力随带钢厚度的增大而增大,基本不随带钢长度变化,带钢沿长度方向的温度变化对带钢临界屈曲应力的影响很小,沿宽度方向的温度变化会导致带钢临界屈曲应力减小,高温下炉辊的热变形会降低带钢临界屈曲应力。

Strip tension control in continuous annealing furnace is one of important measures to ensure its stable operation. The tension of strip changes when the operation temperature or the size of the strip changes. The improper operation is very easy to lead to the break of strip, which has a bad influence on the safety of the equipment operation. A mathematical model of the critical buckling stress of strip was established based on finite element analysis software, Marc to study the effects of strip size, temperature and the shape of furnace roller on critical buckling stress. The results show that critical buckling stress increases with the increase of strip thickness. The length of strip has little influence on critical buckling stress. Temperature difference along the width of the strip can lead to the decrease of critical buckling stress; however, temperature difference along the length of the strip does not have much influence on critical buckling stress. The shape change of furnace roller because of high temperature can decrease the critical bucklin~ stress.