Análise da troca térmica após forjamento dos eixos de acionamento de freio em esteira de resfriamento

Abstract

The process of forging metals is ancient and has been undergoing refuge over the years. They seek to optimize this process, as more efficient companies in order to reduce the manufacturing cycle time of a part. For this, and sometimes more productive, there is no market for robotic solutions. In a robotic forging cell, one of the main points of attention is the cooling of the part, this method directly impacts the manufacturing cycle time. This study aims at the thermal exchange after the drive axles of the brake drum, this way the axle will be observed in a cooling mat, where two methods of heat download was received. Natural cooling with a partial part at a temperature of approximately 950 °C, whose temperature range required for the process is around 50 °C and then the compensation which must act so that the part must act in the process with a temperature later below 50 °C and does not affect the other subsequent processes. With this, a dimensional analysis was carried out, taking into account the behavior of the brake drive shaft after the assembly, to define the effective length of the belt for the whole process. Thus, a dimensional analysis was carried out, taking into account the behavior of the brake drive shaft after heating, so that, in this way, the effective length of the mat responsible for the entire process could be defined. For the effectiveness of the work, tests and practical tests were carried out involving the brake drive shaft, comparing the results obtained in these tests with those found in the analytical study (Global Capacitance Method and Convection-Radiation Integration) and in CFD simulations (Computational Fluid Dynamics) of the cooling process. If there was any discrepancy between the analyzes carried out, it was based on the results of the practical tests to define the length of the mat, whose total cooling time considering the two processes involved was 37.5 min, with 13 min for cooling through the natural convection and 24.5 min for forced convection. Unlike the results found via CFD simulation and analytically through calculations, where the time found for cooling in natural convection through the global capacitance method was 38% higher than that found in the practical simulation and by the integration method 45% lower, already in the simulation CFD time closed with that found in practice. For the calculations involving forced convection, the result obtained by the global capacitance method was 30% greater than that found in practice, considering the integration method, this difference decreased by only 6% greater. In the CFD simulation, this value was extrapolated and reached 60% higher than that found in practice. Based on this and considering the results found in a practical test, the mat reached the dimensional definition of 9 m in length. [resumo fornecido pelo autor]