Taking the small module spiral bevel gear as an example, the cold precision forging simulation research is carried out. The DEFORM-3D software is used to simulate the stress distribution, defects, die wear and material flow in the machining process. It can predict the problems in actual production with high accuracy. By analyzing and comparing the influence of some basic parameters of spiral bevel gear on forging, Then the feasibility of forging die is simulated. Finally, the machining method and dressing technology of die are described.
DEFORM-3D is a powerful simulation software for complex metal flow forming analysis. It is a process based simulation software. By setting the simulation environment, the results of material flow, equivalent stress distribution, die stress and damage in the forming process can be analyzed. It is suitable for simulating metal 3D forming. The graphical interface provided in the software is powerful and intuitive, which can easily input data and observe the result data. The automatic meshing function provides convenience for users Post processing is convenient for users to operate and analyze the results.
DEFORM-3D has the following features:
- DEFORM-3D integrates various environments such as hot, warm and cold forming, and is suitable for simulation systems in different situations.
- If there is an error in the operation process, it has the function of automatic re meshing to prevent the interruption of the intermediate process.
- It integrates the forming equipment models such as screw press, hammer forging machine and mechanical press, which can be easily selected.
- The properties of die and forging blank can be selected from elastic, rigid plastic, THERMOELASTIC-PLASTIC and other models, which are suitable for forging simulation in different situations.
Firstly, through DEFORM-3D software, the cold forging environment is established, the die and blank model of precision forging small die spiral bevel gear are introduced, and the simulation parameters are set for forging simulation; Then, the forming process, equivalent stress distribution and stroke load curve of the large wheel are analyzed, the dynamic process of spiral bevel gear forming is described, and the change trend of loading force in the forming process and the theoretical loading force required for forging are obtained. The influence of geometric parameters on precision forging results is studied. By changing the pitch cone angle and cogging volume, the following conclusions are obtained under the conditions of this example:
- The loading force of precision forging of large wheel of spiral bevel gear decreases with the increase of pitch cone angle, while that of small wheel increases with the increase of pitch cone angle.
- The loading force in the precision forging process of spiral bevel gear is directly proportional to the volume of tooth slot.
Then, the simulation and analysis of the die drawing process of precision forging are carried out. From the perspective of the small module large wheel in this example, under the condition of direct die drawing, the die drawing force is only one hundredth of the loading force. There is no obvious change to the tooth shape after die drawing, and the die drawing process is smooth. For the small wheel, the die drawing force reaches one tenth of the loading force. Such a large die drawing force affects the tooth shape of the small wheel, The final deformation of the spiral bevel gear pinion is serious and the die is difficult.
Finally, the machining technology and correction method of spiral bevel gear die are described, the EDM technology is described and its advantages and disadvantages are analyzed, the NC machining die method is briefly described, and two methods of trimming die are listed.