Study of the friction coefficient during the steady-state process of continuous hot rolling of steel strips in conditions of the 1950 industrial mill

Abstract

This paper describes a method for determining the value of the friction coefficient in a steady-state hot rolling under industrial conditions of the casting and rolling complex of “Vyksa Steel Works” located in Vyksa. The algorithm implies the forward slip method for determining the friction coefficient using the Ekelund formula. Measurements of hot rolling technological parameters from sensors are used as input parameters. Mathematical formulas are implemented in the ibaAnalyzer software, with the help of calculations are made for several thousand strips and data on the friction coefficient are obtained under various conditions. The data processing results demonstrate a normal distribution of the friction coefficient. The highest value of the friction coefficient is typical for the first finisher stands F1-F2, and the lowest values are found for the thinner gauge products rolled at high speed. The influence of the working layer of the work rolls on the friction value is demonstrated. High-chromium cast iron rolls have lower values of the friction coefficients, in contrast to indefinite cast iron, which is used for the working layer of the last finisher stands of mill 1950. A detailed comparison of the results with the classical methods for determining the friction coefficient in a steady-state process has been carried out. The dependence of the ratio of the friction coefficient during initial entry to the steady-state friction coefficient was refined.