Research On Processing Technology Of Machining Deep Hole In Sheet

With the growth of people’s environmental awareness, green manufacturing is increasingly becoming the trend in machinery manufacturing in 21st century. And hole machining in the mechanical processing occupies an important proportion, thin sheet drilling hole is a part of hole machining. So it is necessary to improve the method of thin sheet drilling hole.The processing technology of machining deep hole of thin sheet through friction which uses plasticity and friction between bit and workpiece is a process. The friction makes the workpiece temperature of machining position increase and produces plastic flow which forms the hole wall and makes the depth of hole be more than the sheet thickness. Compared with the traditional thin sheet hole processing method, this process has advantages as follows:improving the linking strength among sheet, saving material, improving production efficiency, having no coolant and chip, having better quality holes, having a whole and rational metal streamline distribution and so on. The processing technology of machining deep hole of thin sheet through friction is a new hole processing technology. With the growth of people’s environmental awareness, there will be a growing emphasis on energy-saving technologies and this technology must have broad application prospects.This paper takes coulomb friction and stick friction belonging to tribological principle and sheet bulging theory belonging to plastic processing technology as basic 3.in the first place. Then bulging mechanical models are established for spherical bit and conical bit. Theoretical analysis is done for the force of forming to obtain influence factors of this force. Performance characteristics of current domestic tool material is analyzed and rational carbide is chosen as bit material of machining thin sheet deep hole. And spherical and conical spherical shape bit are made and chosen as experiment tool. The effect of bit shape and process parameters on hole quality is researched. Then the theory of friction heat leading workpiece thermal deformation is used to do experiment of machining thin sheet deep hole and performance change and organization change of workpiece deformation zone is researched to provide basis for further optimization of process parameters. The drill breakage is researched at last, the wear mechanism of carbide bit is researched with SEM and the main wear form of bit is obtained.The feasibility of the processing technology which machines deep hole of thin sheet through friction can be proofed through experiments. The hole getting through this method can be capable to process screw hole wholly.