GRINDING WORKING ROLLS OF HOT ROLLING MILLS

In connection with the development of technology nonprogrammer rolling on modern hot rolling mills the increasing use of the most widely application get a mills equipped with axial shifting of working rolls. Such rolls have S-shaped profile described by the polynomial n-power. Grinding of profile occurs between the mounting batches. For the rational use of production areas, for the reduction of the park of the rolling-mill rolls and ensure geometric accuracy profiles, which are used in the algorithms of the strips profile and flatness control system, it is expedient to grinding rolls in hot condition. For this you need to take into account change of the roll profile because of the thermal expansion which depends on the program of rolling and time elapsed from the moment of dumping from the mill to grinding. For determining the correction factors of the polynomial studies of the thermal profile have been carried out. According to the results of studies it is established that the amount of adjustment of the polynomial coefficients should depend on the difference of temperature at the edges and in the middle of the roll and on the average width of the rolled strips. The paper presents the results of mathematical modeling and experimental research of thermal condition of working rolls. Described algorithm of determining the correction factors of the polynomial of the S-shaped roll profile allows grinding the rolls in the hot condition and ensuring the reception of the desired profile in cold condition.