Thermal modelling and characteristics analysis of high speed press system

The traditional thermal model of presses neglects the effect of roughness between two contact surfaces on the contact conduction coefficient, which causes the analysis to have a low accuracy. The primary objective of this work is to propose an improved thermal model of the high speed press system with the thermal contact resistance between solid joints and the change of the heat generation power with the temperature of bearings considered to analyze its thermal characteristics. Based on the fractal model and the change of the heat generation power, a complete thermal model for the high speed press system is developed. The temperature histories and the time for reaching thermal equilibrium condition of the high speed press system are explored by the finite element (FE) method. The experimental results demonstrate that the complete model is more accurate than the model without considering the thermal contact resistance and the change of the heat generation power. The thermal expansion of the high speed press system is also investigated, which can provide a theoretical basis for design of structure and intelligent lubrication system to improve its precision. The traditional thermal model of high speed press system always neglects the effect of the thermal contact resistance between solid joints and the change of the heat generation power with the temperature of bearings. In this work, based on the fractal model and the change of the heat generation power, a complete thermal model for the high speed press system is developed shown in Fig. 1. The experimental results demonstrate that the proposed complete model is more accurate than the model without considering the thermal contact resistance and the change of the heat generation power. [Display omitted] •The temperature of the press increases quickly at the early stage, and gradually saturates.•The thermal displacement results in downward migration of the lower dead point position.•The temperature of the top press frame begins to rise, which leads to upward migration.•The total maximum thermal displacement becomes larger due to the thermal contact resistance.