Abstract
In modern metallurgical industry, two-stand reversing cold rolling mills (“CCM”) are used for the production of cold-rolled sheet steel in quantities of up to 500-900 thousand tons per year. On such mills, as on two-stand, four-stand and six-stand continuous mills (“TCM”), the metal may be deformed two, four or six times. A comparison of rolling in a four-stand continuous mill and a two-stand reversing mill in four passes shows that the CCM technology, unlike the TCM technology, is characterized by the use of maximum reduction in the first pass, and specific tension is generally lower than in the four-stand continuous mill. In the first two (forward) passes of the CCM mill, the rolling speed is set on the second stand and does not exceed 70% of the maximum permissible according to the technical characteristics of the mill, and in the last two (reverse) passes - on the first stand and, as a rule, does not exceed 90% of the maximum possible. At the same time, the speed of the second stand in direct rolling and the speed of the first stand in reverse rolling may not meet the condition of second volume constancy. As in the TCM mill, there is a tendency to decrease the rolling speed with increasing strip thickness and width. With the application of multiple regression analysis at a confidence level of 95%, statistically reliable dependencies were obtained for the selection of private compression, specific tension and speed in the design of resource-efficient technological strategies for the production of competitive rolled products using two-stand reversing mills.
Keywords:
cold rolling process, continuous cold rolling mill, two-stand reversing cold rolling mill, reduction, specific tension, rolling speed.