Rolling Mill Vibration Research: Decades of Exploration and Unresolved Technical Challenges

Research on rolling mill vibrations has spanned more than half a century, with numerous scholars and experts focusing on vibration phenomena occurring in cold continuous mills, leveling mills, hot continuous mills, and medium plate mills. By reviewing extensive literature and undertaking research projects on vibration issues in ten continuous rolling lines, this paper summarizes and generalizes the study of rolling mill vibrations. In summary, research on rolling mill vibrations primarily centers around three aspects: how rolling mills vibrate, why they vibrate, and how to suppress such vibrations. The specific research content and progress are described as follows.

1. Inherent Mechanical Characteristics of Rolling Mills  
In studying the inherent dynamic characteristics of rolling mills, research has evolved from using simple "spring-mass" models to analyze vibration modes and natural frequencies to employing finite element methods for modeling and modal analysis, marking a significant advancement in research methodology.

2. Vibration Transmission Process in Rolling Mills
Regarding vibration transmission, understanding has progressed from attributing mill vibrations solely to meshing frequencies of gears, gearboxes, and universal joints in the drive system to incorporating nonlinear vibration theory for analyzing vibration propagation, thereby increasing the complexity of the problems studied.

3. Capturing Rolling Mill Vibration Phenomena  
In field-based vibration monitoring, techniques have advanced from temporary testing methods such as light oscilloscopes and tape recorders to online monitoring systems utilizing industrial computers for data acquisition and analysis. This evolution has significantly improved the reliability and accuracy of vibration signal measurements, enriched analytical capabilities, and provided first-hand, reliable data for investigating vibration mechanisms.

4. Mechanisms of Rolling Mill Vibrations  
In terms of vibration mechanism research, studies have expanded from examining self-excited vibrations caused by friction in roll gaps to applying nonlinear dynamics theories involving periodic bifurcation and chaotic motion, making theoretical analyses increasingly complex and sometimes difficult to solve.

5. Measures to Suppress Rolling Mill Vibrations  
From the perspective of vibration suppression, when vibrations occur, mills are often forced to reduce speed, replace rolls, or adjust process conditions to alleviate the problem. Common measures in continuous mills include modifying lubrication conditions in the roll gap and optimizing roll arrangement principles, aiming to minimize vibration within a limited range.

In conclusion, despite decades of dedicated and persistent efforts by many researchers and experts over the past fifty years, a clear, rational, and universally accepted explanation of rolling mill vibration mechanisms remains elusive, and no universally effective method for suppressing these vibrations has yet been established.