The spider heating process of finite element simulation

Finite element simulation 2019 - cross axis heating process 01 - 20 Ma Jitang liu ( Taier Heavy Industry Co. , Ltd. ) Heat insulation heat treatment time is generally according to the steel grades, furnace charging quantity and style, the size of the workpiece shape and cross section, the performance requirements of workpiece, the traditional empirical formula is used to determine the. In the actual production, often based on experience and artifacts effective thickness ( mm） To calculate the heat preservation time, in the air furnace quenching heating temperature holding time is about the meter to the temperature, the effective thickness of 1 mm/min. This article USES the finite element method to simulate the cross shaft heat insulation process of the change of the temperature field, and the temperature measurement in the actual production verification, to optimize the different specification the spider heat insulation technology provides the reference basis. 1. Modeling the spider modeling, cross the cross shaft head diameter is 225 mm, as shown in figure 1, symmetrical structure, take a cylindrical shaft head 1/12 modeling, as shown in figure 2. 2. Heat insulation simulation and validation cross cross adopted 20 cr2ni4w carburizing steel thermal physical parameters. The initial conditions for temperature rising test cross shaft temperature 340 ℃. Boundary conditions with the third kind boundary condition, namely convection boundary plus radiation boundary. Heating process is relatively slow, the integrated heat transfer coefficient in the furnace using the calculation method described in the literature. Heating conditions set to heat the atmosphere in the furnace temperature. The spider in reheating furnace heating insulation ( See figure 3) In its core insert a thermocouple, asbestos block center hole. Near the cross shaft paste on the surface of a thermocouple, measuring the surface temperature. Heat insulation temperature 850 ℃, holding time ended up with after the temperature of the measured the core. The spider heating process simulation as shown in figure 4. 3. The result analysis of cross shaft surface and center of the simulation and measured results are shown in figure 5. Can be seen from the figure 5: the core of the simulation and the measured temperature curve, the core in the heating stage, the simulated temperature than the actual heating up fast, mainly because of the heat transfer coefficient is determined according to the formula, while the formula of the adaptive recognition [in the engineering 2] The real heat transfer coefficient, still exists a certain deviation; Surface simulation results and the measured temperature error is very big, think to cross shaft surface thermocouple, not body surface temperature measurement, but between the furnace temperature and atmosphere temperature between the surface temperature. On the surface of the measured temperature and furnace temperature control instrument in furnace atmosphere temperature is more consistent. 4. Conclusion of cross axis heating process is simulated, and the temperature measurement verification at the scene of the production. Axis of cross department heating curves of simulation in conformity with the measured, for the future reference for optimizing spider heating process optimization. Source: the metal processing ( Hot working) 17, 2016