The report of the firm SMS Sehloemann-Siemag Aktiengellschaft by H. J. Pelking, chief of the design department of cold-rolling mills, presented a concept of producing cold-rolled steel which made it possible to fulfill the highest requirements imposed on quality and which was used, in particular, when designing the 2000 mill for the Magnetogorsk integrated metallurgical plant (MMK) with an annual output of about 2 million tons. Designing is carried out at four levels: determination of the main parameters of the rolling mill (diameter of the work rolls, etc.), optimization of the drive; development of means determining the quality of the rolled product (minimum variation of thickness, flatness, surface quality); technological regulating contours; organization of the continuous process for increasing productivity and reducing unspecified lengths. After 1980, SMS delivered more than 140 stands for cold rolling strip with a minimum variation of thickness and good flatness achieved by means of CVC systems with gradual regulation of the convexity of the working surface of rolls, multizone cooling, and additional bending of the rolls. The CVC system has already been used for about 10 years, 170 two-, four-, and six-high stands, including 60 stands for cold rolling, are equipped with it. Axial movement of the CVC rolls in Morgoil bearings (Fig. 1)permits using the two-high stands, in particular, for temper rolling carbon-steel strip and for producing aluminum strip with a mirror surface at the enterprise ARW Aluminium Raushofen Walzwerk GmbH (Austria). Figure 2 shows a HS CVC six-high cold-rolling stand equipped with systems of bending and horizontal movement of the work HS and intermediate CVC rolls, the drive of which is realized through backup rolls. The systems for movement of the rolls along with hydraulic screwdown mechanisms and multizone cooling provide the obtainment of high-quality strip according to the HTR (High-Tech-Rolling) concept.
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