Simulation of type selection for 6-high cold tandem mill based on shape control ability

Abstract

A theoretical method for selecting strip rolling mill type that considered shape control ability was established using the figure alteration range that was worked by the alteration track of vector expressing strip's cross section (crown) to express the shape control ability of rolling mill. With the mathematical models and simulation software that were developed by the authors' own models, four types of mills were aimed, including HCM (6-high middle rolls shift type HC (high crown) -mill), HCMW (6-high middle rolls and work rolls shift type HC-mill), UCM (6-high middle rolls shift type HC-mill with middle roll bender) and UCMW (6-high middle rolls and work rolls shift type HC-mill with middle roll bender), and the shape and crown control ability of every mill type was analyzed and compared. An appropriate arrangement mode of tandem mill was brought forward. The results show that UCMW mill is a perfect choice for controlling shape and crown, and the area of control characteristics curve of UCMW (or UCM) is twice than that of HCM, but UCM mill is also a good choice for its simple frame. In other word, the shape and crown controlling ability of UCMW mill is better than that of UCM mill, but the frame of UCM mill is simpler than that of UCMW mill. As for the final type of mill, should be synthetically decided by thinking over fund and equipment technology.

Numerical Analysis of Intermediate Roll Shifting–Induced Rigidity Characteristics of UCM Cold Rolling Mill

“…The vertical and transverse rigidity characteristics of the mill are important factors in determining the thickness and the flatness control accuracy of the exit strip. For an ordinary four‐high mill, such as the four‐high High Crown (HC) mill, when the structure of the mill is fixed, the vertical and transverse rigidity of the mill remain basically unchanged. The six‐high Universal Crown Control mill (UCM mill) developed by Mitsubishi‐Hitachi Metals Machinery (now Primetals Technologies Japan Ltd., Tokyo, Japan), however, adds a pair of intermediate rolls that can be moved axially on the base of the four‐high HC mill, and the vertical and transverse rigidity of the mill changes as a result of the intermediate roll shifting (IRS) value by altering the elastic deflections of the roll‐stack and the flattening state between the rolls .…”

Research and Development Trend of Shape Control for Cold Rolling Strip

“…A vector evaluation method for overall control of the whole crown and center crown was proposed by Peng, et al [59]. The method can be used to analyze the advantages and disadvantages of 6-high HC, 6-high CVC, 4-high CVC, and ordinary 4-high mills and thus serves as an analytical tool and an important reference for rolling mill type selection.…”

Novel method of flatness pattern recognition via cloud neural network

“…3, where input is d i (i = 1, 2, 3, 4) and output is u i (i = 1, 2, 3, 4). Flatness pattern recognition process, in reality, is the process of forecasting the membership degrees between the sample to be recognized and the basic patterns (Peng et al 2007). Identifying process is as follows:…”