喇叭形厚差波动问题的分析与解决

Analysis and Solution to Trumpet Shaped Thickness Deviation

热连轧生产罐体料时,3机架热精轧机组出口带材厚差变化趋势呈现喇叭形现象,其波动频率是F2机架工作辊转动的2倍频。针对这一现象,通过IBAAnalyzer分析工具详细分析现场轧制相关的工艺数据,明确了厚差呈现喇叭形波动是F1机架出口带材平直度超出余裕区间导致。通过采取加快粗轧轧制速度、提高粗轧轧制节奏、优化分配工作辊弯辊力等轧制策略优化措施,保证粗轧轧制出的板坯凸度与3机架精轧机组出口的目标凸度相匹配。同时,以比例凸度恒定为原则,F1机架、F2机架在生产全过程投入PC自动比例凸度控制,确保精轧机组各段带材在平直度余裕区间内实现比例凸度的增减,保证板型良好,有效地保证了轧制的稳定性,从而解决了厚差变化趋势因板型不良呈现喇叭形的问题。

ABSTRACT:During the can body was in production in a aluminum hot tandem mill, a trend of trumpet shaped thickness deviation was appeared on the exit of 3 stands hot ifnishing mill, and the lfuctuation frequency is twin as the F2 roll rotation’s. In view of this phenomenon, the detailed analysis for the related rolling process data on ifeld was carried out with the tool of IBA Analyzer, it was cleared that the trumpet shaped thickness deviation was caused by the exit strip of F1 where the lfatness was out of the lfatness margin interval. By improving the rolling strategy through improving rougher rolling speed, rougher rolling rhythm, and optimizing distribution of rougher work roll bending force, to ensure the proportional crown of transfer bar is matched with the target proportional crown of 3 stands exit strip. At the same time, with the principle of constant proportional crown, PC of F1 and F2 stand was put into automatic mode during whole production to realize increasing or decreasing proportional crown within flatness margin interval in each section of the finishing mill to guarantee the well flatness, it effectively ensures the stability of rolling. The problem of trumpet shaped thickness deviation caused by poor lfatness was solved effectively.