Based On Ug ¢ò Blade Forging Die Cad System

A blade is a very important part of aircraft抯 engines. Precision forging has many advantages over conventional forging in mechanical properties and in decreasing costs. Therefore, precision forging is urgently needed in manufactories of aircraft抯 engines. In order to apply this technology in practice, special development of CAD(Computer Aided Design) for the blade precision forging die is systematically studied on the basis of UGII(V. 14) in this thesis. The main content is as below:According to the design procedure of the blade forging part, the data of the blade surfaces is changed to that of the corresponding forging blade surt~ces. Software engineering method is used in coding every changing step into a separate sub-function, which is called in the main function. The changing procedure includes: extending of the blade on the tip, extending of the blade on the root, expanding of the surfaces of the blade, extending of the blade on both sides, calculating the balance angle, changing the coordinate system, changing the data on the consideration of the shrinking and the reflecting of the blade material, etc.A blade surface is bended and distorted in three dimensions. The blade surfaces have to be precise and smooth to satisfy the gas dynamic demand. The molding procedure includes dealing with the end points of section curves, fitting the curves with the defining points, smoothing the curves, sheet molding of the blade surfaces and solid molding of the blade body.Dimensions of usually used rabbets and bosses are analyzed deeply. Libraries (driven by dimensions) of rabbets and bosses are set up by User Defined Feature of UGh.The position relationships between the blade bodies, the rabbets and the bosses of the blade forging parts are studied. According to the relationships, the solid bodies of the blade forging parts can be generated from the three parts. According to the structure of the final forging die, the flash groove is studied and coded into a separate sub-function. In order to split the upper and under dies, a sheet body of the separatingsurface is coded into a sub-function. In this thesis, how to calculate the parameters of the blade die and how to generate the solid body of the final dies using the interface functions of UGh are discussed. This thesis also gives the method of getting the volume and the mass of the blade forging part.