Papers by Keyword: Strip Profile

Abstract: Optimisation of the physical and mechanical properties of cold rolled thin strips is achieved by controlling the rolling parameters. In this paper, the factors affecting the low carbon steel thin strip profile of asymmetrical cold rolling have been studied at a speed ratio of 1.3 without lubricant applied. The effect of rolling parameters on the resulting microstructure was also investigated. It was found that under dry condition, work roll shifting and work roll cross angle can improve the strip profile, and the improvement is more significant with an increase of work roll cross angle rather than that of work roll shifting. A slight change in microstructure was evident with increasing work roll shifting values. In addition, effects of rolling parameters on the strip profile and microstructure have also been discussed.

Abstract: Cold rolled thin strip has received a great deal of attention through technological and theoretical progress in the rolling process, as well as from researchers who have focused on some essential parameters of strip such as its shape and profile. This paper describes the development of a 3-D finite element model of the shape of thin strip during cold rolling to simulate the cold rolling of WCS (work roll crossing and shifting) in asymmetric rolling. This finite element model considers the asymmetrical rolling parameters such as variations in the diameters of the rolls and the crossing angle as the work roll shifts on the strip during cold rolling. The shape and profile of the strip are discussed in the asymmetrical and symmetrical rolling conditions, while the total rolling force and distribution of stress are discussed in the case where the roll cross angle and axial shifting roll changes. The results can then be used to control the shape and profile of thin strip during rolling.

Abstract: Strip profile control during rolling is required to assure the dimensional quality of rolled thin strip is acceptable for customers. Throughout rolling, the strip profile is controlled by using the advanced shape control rolling mill, such as the combination of work roll crossing and shifting during asymmetrical rolling, the one of the valuable methods to control the strip profile quality in rolling process. In this paper, the influences of cold rolling parameters such as the crossing angle and axial shifting value of work rolls on the strip profile are analysed. The strip shape control is discussed under both symmetrical and asymmetrical rolling conditions. The obtained results are appropriate to control the rolled thin strip profile in practice.

Abstract: Shape setup model (SSM) plays a critical role to achieve satisfactory precision of strip shape in hot strip mill process (HSMP). In this paper, the process of SSM is introduced, taking 1700mm HSMP line in Ansteel as the research object. Special attention is focused on the gap crown model, which is the foundation of SSM. And the allocation strategy of reference values for mechanical actuators is presented. Then an off-line simulation method is proposed to obtain several key parameters of the model. SSM has been put into practical use and proved to be effective to control strip flatness and profile by high accuracy.

Abstract: In order to analyze the effect of entry strip thickness, entry strip crown and intermediate roll shifting on strip profile and rolling force distribution, a three dimension finite element model of rolls-strip in UCM mill was established and employed. The results showed that the increases of entry strip thickness and entry strip crown would lead to the increase of exit strip crown and edge drop under the same total rolling force; the strip crown and edge drop would be decreased if the intermediate roll shifting δi was decreased. Moreover, the rolling force distribution also was analyzed in details by changing the entry strip thickness, the entry strip crown and the intermediate roll shifting.

Abstract: The industrial production of aluminium strip comprises a rather long process chain. One of the characteristics of aluminium alloys is that a number of final strip properties are influenced considerably already at very early process stages. Since it is practically impossible to run large variations of controlled process changes on an industrial mill experimentally, Through Process Modelling (TPM) has been in focus of research and has developed into a valuable tool to design process chains with a view to achieving desired properties. Metallurgical models in combination with (plasto-) mechanical/thermal models trace variables of state through the process chain down to the final operation. However, there are further important properties of the product, which may be generated as consequence of the total production history. Predominant examples are the strip profile and flatness and the product surface. These properties do not only result from the processes settings, they may also have a strong back-effect on the process performance itself. As a consequence they may also affect the metallurgical properties. This paper shows representative computations of in-dustrial aluminium rolling process steps to evaluate the interactions of different mechanisms taking place in the rolling processing chain, with a special attention to profile/flatness, surface and metal-lurgical properties.

Abstract: Due to the problems of very serious wear, serious scale and poor ability to controlling strip shape of work roll, considering the advantages/disadvantages of HSS roll and the field practices, a 3D elastoplastic FEM model of rolls system with strip, which is used to analyze the ability of strip shape control of rolls system when HSS rolls work at any two stands of F1-F4, is modeled. The calculating results sho: The control ability of mill is relative greater when HSS rolls are used at F4, the advantages of HSS roll are not taken fully if HSS rolls work at F1 and F2. And HSS are available for either F2 or F3, furthermore, F3 is better for shape control. The analysis results are verified by the experiments. A strong theory base of application of HSS rolls in Hot Strip Mill is brought forward in this paper.