We describe an integrated tension controller design for a tandem cold rolling mill in steel plants. To achieve stable rolling and ensure strip quality, it is very important to control the tension of the cold rolling mill. Previous researches examined only the operation of a single stand. But it is not sufficient to examine the operation and effect of whole stands because the operation is wholly interdependent. To solve the problem, this paper proposes an integrated control strategy for tension control of tandem cold mill, the full stand model for the tension system of a tandem cold mill is built, and the interaction of all the stands is analyzed. Then applying the method of μ-synthesis design a integrated robust tension controller. Simulation with the practical data proves the integrated robust tension controller can achieve more robust performance than that of typical industrial approach.

According to the characteristic of high-strength strip, the roll profile configuration and change of CVC tandem cold mill are analyzed. Through the establishment of FEM model, the influences of three representative forms of roll profile configuration on high-strength strip flatness control in CVC cold rolling mill are compared, which are conventional back-up roll / CVC intermediate roll, back-up roll with CVC compensation / CVC intermediate roll, VCL+ back-up roll / HVC intermediate roll. Compared with the other two roll profile configuration, the configuration of VCL+ back-up roll / HVC intermediate roll increases 26.74% in crown adjustment domain of roll gap and 22.09% in lateral stiffness of roll gap, decreases 27.43% in contact pressure peak values between rolls. The new roll profile configuration has obtained industrial applications. Production data indicate that the control accuracy of high-strength strip is improved, also the wear of back-up roll. Significant application results have been achieved.

This article suggests that divide the strip surface quality into the damage class, the adhesion class as well as the surface vision class. In order to improve the surface vision quality of the tin plate, the chromaticity of gloss and lightness are used to measure the tin plate surface vision quality. Predictive models of gloss and lightness are established to determine the influencing factors by stepwise regression in the article. The research indicats: the gloss and lightness of tin plate are closely related with tin coating weight and the roughness of tin mill black plate, including profile arithmetic average error and superficial peak density. By enhancing the roughness control accuracy of tin mill black plate, the surface visual quality of tin plate has been greatly improved and the chromatic aberration after printing is solved.

Superalloy IN718 large tube is used in critical jet engine applications, while manufacturing such components, the control of temperature during tube hot extrusion is of paramount importance. To determine the relation between technological factors and the temperature rise, extrusion force during tube hot extrusion of superalloy IN718, a numerical model was developed to for the large tube hot extrusion through die and over mandrel. The constitutive behaviour of the material and friction at the extrusion temperatures are established as a thermoplastic process. In order to investigate the influence of technological parameters of extrusion process on the temperatures rise and extrusion force, then the extrusion variables such as friction factor, ram speed, tool and billet preheating temperature are taking into consideration. Besides tool preheating temperature, other parameters have a great influence on temperature rise of billet during the extrusion process. All of technological parameter of study in this paper have a significant influence on the extrusion force. Moreover, based on the simulation results, the case with tool preheating temperature of 300°C should avoid during the technology making.

In a 1220mm temper mill, the cross bow was serious, which seriously affected the unit’s output and efficiency. In order to solve this problem, the mechanism of cross bow is studied in rolling of single-roll transmission temper mill. First, established the FEM of the single-roll drive temper mill rolling, analyzed the distribution factors of vertical extension in thickness. Second, used the method of symplectic elasticity to establish the analytical calculation model to study the relationship between the cross bow with the uneven vertical extension, explained the mechanism of cross bow. Then, used ANSYS to establish finite element model which further analyzed the cross bow under different distribution of extension in width direction. On the basis of analyzed the mechanism, proposed measures to reduce the value of cross bow. These measures have been applied in production; the effect of application was obvious.