冷轧机轧制参数对振动临界速度的影响

Influence of rolling parameters of cold rolling mill on vibration critical speed

轧机升速进入高速轧制阶段后,常发生振动现象,其中三倍频程垂振最为强烈,以此为研究对象,通过分析振动机理得出辊缝间产生的负阻尼效应导致振动临界速度降低,自激振动更易形成。对已投产轧机的抑振改进不宜进行大范围的结构改进,应从轧制参数的角度进行分析。运用计算机仿真方法研究轧制参数中乳化液黏度、带钢入口厚度、带钢出口厚度、带钢变形抗力、辊缝间阻尼对振动临界速度的影响,获得相应的非线性关系,并通过轧制试验进行验证。通过调整相关轧制参数,提升振动临界速度,使之总高于轧制速度,保证轧机的稳定运行。

Vibration phenomenon often occurs in the high-speed rolling stage of rolling mill,and three-time frequency vertical vibration is the strongest.For this rolling mill,it is found that the negative damping effect between roll gaps reduces vibration critical speed by analyzing vibration mechanism,and the self-excited vibration is more easily to form.The improvement on vibration suppression of rolling mill used in production should be analyzed by adjusting rolling parameters without changing the structure aggressively.Then,influences of emulsion viscosity,strip entry thickness,strip exit thickness,strip deformation resistance and roll gap damping on the vibration critical speed were studied by computer simulation,and the corresponding non-linear relationship was obtained.Then,it was verified by rolling experiments.Furthermore,the vibration critical speed is enhanced by adjusting rolling parameters to ensure that it is consistently higher than the rolling speed,which brings the stability to the operation of rolling mill.