Failure Analysis Of The Foot Roller In The Wide Surface Of The Mold

In this paper, the study object is a mold wide face foot roller of a steel factory. In actual production, the foot rollers always has the problem of not rotating( but the bearing rotates freely after disassembly), deforming and burning out between roller sleeve and foot roller. Use finite element analysis method to identify the causes of the foot roller deforming failure and improve it.Taking the influence of slab into consideration. In order to make the contact boundary conditions of slab heat radiation and roller to slab more in line with the actual situation. We established the whole system model of the foot roller and slab. Imposed the temperature load to the overall system of foot roller-slab and calculated the temperature field of the foot roller.Sequential coupling method was used to import the temperature field results in the heat load form to structural analysis, calculated the stress and the deformation under the effect of thermal force and mechanical load. Since the foot roller will creep while be used at high temperature for a long time, and according to the use of foot roller status, the stress and deformation of foot roller for using 240 hours and 1000 hours should be solved.The results showed that the maximum equivalent stress of the foot roller sleeve is350.92 MPa, which is far less than the yield strength of 35 CrMo steel at 600?. The safety factor is 1.38. So the strength of the foot roller was proved to meet the use requirements before creep. After creeped, the stress of the roller sleeve is far greater than the creep limit at 600?and endurance limit at 600?of the 35 CrMo steel. The foot roller can't meet the strength requirements. Before and after creep, the axial deformation of the roller sleeve is larger than the gap between the roller sleeve and the chock of the foot roller. The roller sleeve is easy to be seized-up. Meanwhile, the deformation in the vertical direction is too large when it is creeping. The creep strain of foot roller is larger than the required creep strain limit. According to the simulation results and the actual situation analysis,high temperature was proved to be responsible for the foot roller bending failure.According to the analysis results, the paper proposed the way of increasing the radius of the roller sleeve to reducing the temperature of the foot roller. By comparing the simulation results with the former, we found that the strength and stiffness of the foot roller get greatly improved. The method of improving meets the requirements.