Sizing Design for 4-High Cold Rolling Mills

2014 ◽  
Author(s):  
Andrew W. Nelson ◽  
Feng Zhang ◽  
Arif S. Malik ◽  
Mark E. Zipf
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Design Approach ◽  
Rolled Sheet ◽  
Rolling Mills ◽  
Roll Bending ◽  
Multidisciplinary Analysis ◽  
Cold Rolling Mills ◽  
Flatness Control ◽  
Geometric Quality

As the demand for thin and ultra-thin gage for cold-rolled sheet metals increases, cold rolling manufacturers and sheet metal producers must utilize technological advancements to stay competitive globally. To manufacture a competitive rolling mill, the mill designer must identify an appropriate mill configuration, roll sizes, and flatness control systems, etc. The design must be robust enough to accommodate broad product envelopes containing strips of different widths, gages, and materials. At the same time, the mill “sizing” must be competitive by avoiding over- or under-design. These two objectives, designing a robust mill and remaining competitive, tend to conflict, which establishes the need for optimal mill design based on rigorous multidisciplinary analysis. Conventionally, mill design is done using a ‘sequential’ design approach relying heavily on experience. The major limitation of sequential mill design is that it can lead to over-design or under-design since it segregates design tasks for the coupled components, making it difficult to consider many combinations of the design space. The result is a ‘feasible’ rather than ‘optimum feasible’ mill design. This work applies nonlinear programming to optimize the basic design of a 4-high reversing cold rolling mill, subject to static strength, fatigue, and strip geometric quality constraints. The work offers an improved multi-disciplinary design approach based on stress and fatigue analysis of rolls, and an efficient strip profile/flatness analysis to identify suitable design limits for roll bending devices.

Simulation on Hydraulic-Mechanical Coupling Vibration of Cold Strip Rolling Mill Vertical System

2013 ◽  
Vol 694-697 ◽  
pp. 407-414 ◽  
Author(s):  
Hai Sheng Liu ◽  
Jie Zhang ◽  
Kai Fu Mi ◽  
Jun Xia Gao
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Motor Behavior ◽  
Strip Rolling ◽  
Work Condition ◽  
Coupling Vibration ◽  
Rolling Mills ◽  
Mechanical Coupling ◽  
Hydraulic Machinery ◽  
Cold Rolling Mills

Based on vibration problems of a six roller cold rolling mill, hydraulic-machinery coupling vibration system dynamic model of the 2180mm 4-stand tandem cold rolling mills was built integrated the software of MATLAB and ADAMS and simulated. The simulation result was consistent with that of the field test data revealed by rolling mill vibration. Through the comparison of the vertical systems motion displacement, velocity, acceleration under the different work condition, coupling vibration causes and evolution mechanism was analyzed, that had practical value to further control mill motor behavior.

Technical Characteristics and Application for a New Type of 8-Roll Cold Rolling Mill

2012 ◽  
Vol 572 ◽  
pp. 55-60 ◽  
Author(s):  
Peng Liu ◽  
Hong Bo Li ◽  
Zhi Qian Shen
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Work Roll ◽  
Fast Response ◽  
Cold Rolling Mill ◽  
Strip Flatness ◽  
Roll Bending ◽  
Roll Mill ◽  
Flatness Control ◽  
New Type

This paper focuses on a new type of 8-roll cold rolling mill with the back-up bearing roll. Compared to the traditional 6-roll cold rolling mill, a thick-walled bearing roll is used to multi-support the intermediate roll. By the rack, the fan-shaped gears, the eccentric core shaft and the servo-cylinder, the work roll can be pushed down by this screw down device on the top of the mill; By contrast with the 4(6)-roll mill, this type of mill has some characteristics, such as: the small size of rolls, lighter weight, the fast response for the screw down. The bearing roll is fixed by the supporting blocks placed on the rolling-mill housing. So this mill has large traverse rigidity, and this is propitious to the flatness control. By different means of strip flatness adjustments, such as the intermediate roll shifting, the roll bending and the bearing roll adjusting, the strip flatness can be well controlled. The oil-gas lubrication is used in the bearings of the bearing rolls, and the changing rolls equipment is designed for this type of mill too. A series of this type of mills (as 450, 800, 1250, 1450 series) have been produced since it was developed in 1997. The mills for 1250 and 1450 series have been applied in five-stand cold rolling mill and single stand reversing mill, a rolling speed of 800m/min has been achieved.

Performance Analysis of Asymmetrical Roll Bending for Flatness Control of Cold Rolling Mill

2010 ◽  
Vol 145 ◽  
pp. 93-99 ◽  
Author(s):  
Dian Hua Zhang ◽  
Peng Fei Wang ◽  
Wen Xue Zhang ◽  
Xu Li
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Work Roll ◽  
Control Analysis ◽  
Cold Rolling Mill ◽  
Roll Bending ◽  
Flatness Control ◽  
Efficiency Factors ◽  
Self Learning ◽  
Asymmetrical Bending

When there appeared catastrophic asymmetrical flatness defects in rolling processes, especially when the incoming strip is with a wedge shape, the tilting roll can hardly eliminate these defects completely. Moreover, the overshooting of tilting roll will lead to strip break. In order to improve the ability of cold rolling mill for asymmetrical flatness defects control, performance of the work roll asymmetrical bending as well as the intermediate roll asymmetrical bending has been analyzed, based on the actuator efficiency factors of them. In addition, for the purpose of obtaining accurate efficiency factors matrixes of actuators, a self-learning determination model of actuator efficiency factors was established in accordance with the practical rolling processes. In this paper, a 1250 single stand 6-H reversible UCM cold mill was taken as the object of this study, with efficiency factors of asymmetrical roll bending analyzed, which provides a theoretical basis for better flatness control. Analysis shows that the asymmetrical roll bending is significant for asymmetrical flatness control.

Analysis of Contact Pressure between Rolls under Non-Symmetrical Roll Bending of UCM Cold Rolling Mill

2010 ◽  
Vol 145 ◽  
pp. 80-86
Author(s):  
Xu Li ◽  
Dian Hua Zhang ◽  
Peng Fei Wang ◽  
Wen Xue Zhang
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Work Roll ◽  
Cold Rolling Mill ◽  
Slowing Down ◽  
Roll Bending ◽  
Comprehensive Information ◽  
Roll Wear ◽  
Flatness Control ◽  
Traditional Work

. For UCM cold rolling mill, the intermediate roll shifting can enhance the ability of mill for better flatness control, but it will increase the non-uniform distribution of pressure between rolls, as result of a reduced roll life. In order to improve the contact state among rolls in rolling processes and to slow down the roll wear, the distribution of pressure between rolls under different forms of roll bending control has been calculated and analyzed by the influence function method in this paper. For the purpose of obtaining comprehensive information, not only the distributions of pressure between rolls with traditional work roll symmetrical bending and intermediate roll symmetrical bending have been analyzed, but also the distributions of pressure between rolls with non-symmetrical roll bending have been analyzed. All the analyses show that the work roll non-symmetrical bending as well as the intermediate roll non-symmetrical bending can play an important role in the slowing down of roll wear.

scholarly journals State of production sheet steel rolled stock in the world and tendencies of development of cold strip rolling mills

2019 ◽  
Vol 1 (1) ◽  
pp. 15-28
Author(s):  
Ya Vasilev ◽  
D Samokysh ◽  
S Zhuravlova ◽  
Yu Projdak ◽  
R Zamogilniy
Keyword(s):  
Cold Rolling ◽  
Sheet Steel ◽  
Thin Strip ◽  
Maximum Efficiency ◽  
Rolled Stock ◽  
Rolled Sheet ◽  
Rolling Mills ◽  
Cold Rolling Mills ◽  
Deformation Modes ◽  
Rolling Technology

The conditions of production and the most relevant directions of development of technology and equipment of cold rolling mills for the production of thin flat rolled steel are investigated, analyzed and summarized. A comparative analysis of cold rolling technology is carried out, which is implemented in continuous and reversed modes of mill. The technological limitations and criteria for the development of deformation modes on cold rolling strip mills, which allow to expand the assortment towards a smaller thickness, are given. A method for determining the thickness is proposed, and a series of thicknesses of thin (1.5-1.8 mm) hot-rolled break-down are recommended for the production of tinplate of single rolling and thin strips of high quality. The method of calculation schedule drafting on a specific mill is developed. The technique of determination of the smallest thickness of a strip on a concrete mill is presented, taking into account the influence of rigidity of the working cage and features of the force load of the roller node with a decrease in the thickness and width of the strip. The use of the above materials allows to select and justify the optimal variant of cold band rolling technology, as well as to develop rational deformation modes that ensure the implementation of the cold rolling process with maximum efficiency, given the desired range and the required volume of thin cold-rolled sheet steel or tinplate. As a result of taking into account the features of the force interaction of the thin strip with the rolls during cold rolling and the rigidity of the working stands of the mill, the accuracy and reliability of determining the parameters are increased, it opens additional possibilities for expanding the range of cold rolling mills towards smaller thicknesses.

scholarly journals Complex study of deformation mode of working stand of pipes cold rolling mill

2018 ◽  
pp. 93-100
Author(s):  
S. R. Rakhmanov ◽  
V. V. Povorotniy
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Rational Design ◽  
Deformation Mode ◽  
Cold Rolling Mill ◽  
Rolling Mills ◽  
Complex Study ◽  
Cold Rolling Mills

Elaboration of main concepts of working stands reconstruction, providing an increase of their operation strength and improving of rolled pipes quality and at the same time a decrease of metal intensity is an actual task. Solving of the task will result to a great extent in expanding of technological possibilities and increasing of productivity pipe cold rolling mills.Results of complex study of deformation mode of working stands of pipe cold pilger mills of different designs presented. Influence of working stands parameters both existing and of rational designs on quality of rolled pipes determined. The study determined, that thanks to application of roller installation with ring roll passes and new bearings an expansion of technological possibilities of ХПТ 32 mill reached. Increase of rolled pipes quality was reached by utilization in the drive line of ХПТ 32 mill a modernized working stand of rational design, which has a high operation reliability and an increased rigidity.

Study on Flatness Control Strategy of a Single-Stand Reversing Cold Rolling Mill

2014 ◽  
Vol 1004-1005 ◽  
pp. 1193-1197
Author(s):  
Jin Lan Bai ◽  
Hong Zhi Pan
Keyword(s):  
Cold Rolling ◽  
Control Strategy ◽  
Rolling Mill ◽  
Work Roll ◽  
Calculation Model ◽  
Cold Rolling Mill ◽  
Roll Bending ◽  
Pass Schedule ◽  
Flatness Control ◽  
Work Roll Shifting

In this paper, an integrated rolls system deformation calculation model is established based on the influence function method combining with pass schedule calculation, rolls wear and roll thermal deformation calculation, and the corresponding calculation procedure has been developed. Then the influence of work roll bending, work roll shifting and intermediate roll bending on transverse distribution of strip thickness, strip crown, quadratic flatness, and quartic flatness are analyzed with the procedure. According to the analysis result, flatness control strategy of the single-stand reversing cold rolling mill is determined. The flatness control strategy will provide the basis for flatness control presetting of the mill. The practical application shows that the flatness control strategy is suitable for flatness control of the single-stand reversing cold rolling mill.

FEM Analysis of Profile Control Capability during Rolling in a 6-High CVC Cold Rolling Mill

2014 ◽  
Vol 988 ◽  
pp. 257-262 ◽  
Author(s):  
Ke Zhi Linghu ◽  
Zheng Yi Jiang ◽  
Fei Li ◽  
Jing Wei Zhao ◽  
Meng Yu ◽  
...  
Keyword(s):  
Cold Rolling ◽  
Rolling Mill ◽  
Rolling Force ◽  
Fem Analysis ◽  
Continuous Variable ◽  
Cold Rolling Mill ◽  
Strip Rolling ◽  
Roll Bending ◽  
Profile Control ◽  
Control Capability

A 3D elastic-plastic finite element method (FEM) model of cold strip rolling for 6-high continuous variable crown (CVC) rolling mill was developed. The rolling force distributions were obtained by the internal iteration processes. The calculated error has been significantly reduced by the developed model. the absolute error between the simulated results and the actual values is obtained to be less than 10μm, and relative error is less than 1%. The developed model is significant in investigating the profile control capability of the CVC cold rolling mill in terms of work roll bending, intermediate roll bending and intermediate roll shifting.

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