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The technology traditionally used to produce flat-rolled products of nonferrous metals (casting of large ingots -hot and cold rolling with intermediate annealings) is not cost-effective for low-tonnage production (up to 30,000 tons/yr) [1]. There is also the problem of making full use of the continuous-cast coiled semifinished product, since the advantages of high-speed hot-strip mills are not utilized in the case of relatively small volumes of products. In addition, such a technology is very metal-and energy-intensive, mainly due to the large diameter of the work rolls (>350 mm) and the need to perform several intermediate annealings.Given these circumstances, it would be preferable to use an intermediate mill that would allow cold rolling with large reductions (cold reduction) on rolls of relatively small diameter. These requirements are met by the Pilger-type mills developed by the Institute Tsvetmetobrabotka for the periodic cold-rolling of sheet (SPC). The design of the mill incorporates recent theoretical advances in the Pilger-mill rolling of tubes [2, 3]. With allowance for specific features of the manufacture of fiat-rolled products, we proceeded on the basis of the following technological principles: 9 a high degree of divisibility of the deformation process and, thus, an increase in the travel of the work rolls; 9 a relatively large (compared to other mills of the same type) work-roll diameter, to improve the formation of the structure of the metal in the cross section of the semifinished product; 9 rolling of the semifinished product with motion of the rolls only toward the delivery side of the mill. After analyzing well-known designs of Pilger-type mills, we devised a scheme (Fig. 1) for the periodic cold rolling of sheet and strip. The scheme was tested on laboratory mill KhPL-130 [4] and prototype KhPL-650 mills [5]. The rolling operation is performed as follows. The strip 1 is compressed by the two work rolls 2, each of which is installed in a movable cassette. During rolling, the cassettes are moved by the drive 3. The backup rolls 4 roll along the stationary supporting rails 5 that are installed at an angle (in the direction of the delivery side of the mill). The center of each work roll simultaneously moves over a closed trajectory, the lower section of which BoBIB 2 determines the compressive strain distribution. The semifinished product is fed into the deformation zone and undergoes no reduction as the center of the work rolls moves along the section BzB3B o.Several theoretical and experimental studies were performed to optimize the relations between the components of the cassettes, the main drive, and other parts of the mill. A method which is free of the traditional assumptions and is characterized by a high degree of generality was developed to evaluate the effect of the diameter of the work rolls and the length of the instantaneous deformation zone on the structure of the cross section of the semifinished product, the elasticity of the system, and the profile of the supporting rails [6, 7...

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