Development of On-Line Chattering Monitoring and Diagnosis System for Stainless Steel Hot Strip Mills

摘要

A stainless steel hot strip mill had encountered serious vibration problems over the years, which led to chatter marks on the strips causing losses due to rejection. To eliminate these problems, comprehensive vibration measurements and analyses were conducted in this work. The primary causes of chatter marks were identified as being worn work roll bearings of the finishing mill, chatter marks on backup roils generated during the grinding process, and the printing of chatter marks on strips onto pinch rolls with a subsequent resonance of the top pinch roll. An on-line chattering monitoring and diagnosis system was then developed based on these findings. This system issues alarms and shows automatic diagnosis results when chattering occurs so that operators can detect mill abnormal conditions in time and take proper action to avoid continued rolling out of defective strips. This paper describes the creation mechanisms of the chatter marks, the mill vibration characteristics, and the main functions of the on-line chattering monitoring and diagnosis system.