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At present, the hot-rolled sheet shape, the thickness required more and more stringent, can be part of the rolling parameters on field experiments, but due to the complexity of the hot rolling process, the majority of the potential parameters are closely related to the rolling process measurement does not to. Therefore, to obtain the desired rolling parameters must rely on the calculation method for the numerical simulation. Roll consumption rolling industry guzzler. Therefore, the numerical simulation of the hot rolling process, provide the basis and reference for the study of roll failure and roll life. With internationally recognized as the best finite element analysis software, one of the ANSYS First, the establishment of a work roll - rolling finite element model of the hot-rolled sheet, hot-rolled plate finite element dynamic simulation of the process, get the work rolls week after the equivalent stress, temperature, thermal stress curve, the following conclusions: three stress area, rolling contact area, the contact area of ??the support rollers, roll neck roll body junction The greatest change in which the the support roller contact area equivalent stress, the maximum value of 450MPa, here is more prone to the plastic zone. Roll neck roll body junction, due to the constraints larger minimum stress changes. The temperature change of the work roll is relatively large, a maximum of 480 ° C, final stable in 90.25 ° C. Axial and circumferential thermal stress trend line, the maximum value of about 987MPa, small radial stress trend with axial and hoop stress opposite. Crack finite element model of the roll - rolling basis, arranged on the surface of the crack, and seek work roll rotation within a week at different times of the stress intensity factor and J integral analysis of the rolling process stress intensity factor and J-integral variation. The following conclusions: most of the stress intensity factor and J integral values ??are just with the rolling contact contact support rollers. Crack inclination angle of both the impact is small, the crack length and the size of the load is to affect the two main factors. Fatigue life calculation is then carried out, through theoretical calculations and ANSYS fatigue compared draw the work rolls cracks about 5600 weeks of work, crack-free work rolls can work 200 000 weeks, visible crack on the work roll life have a great impact. Finally, the analysis of the critical condition of the crack propagation, the critical conditions for crack propagation speed steel roll: the critical temperature is about 420 ℃, the critical load is about 420MPa, crack initiation angle of about 90 °, concluded with the classic composite type crack guidelines compared to is little overall error. To improve the working life of the high-speed steel rolls and prevent crack propagation, this thesis provides a theoretical basis and reference views, have certain guiding significance and reference value of the actual production.
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