Measurement-grinding Integrated Technology Of Inner Weld For Thin-walled Cylindrical Part With Large Depth-diameter Ratio

With deep hole and thin-walled structure,engine combustor flame tubes have been widely applied in aerospace,transportation and national defense fields.Engine combustor flame tube is made by high strength steel or other difficult machining materials,and it is a good solution to achieve the purpose of machining engine combustor flame tube by the process of butt welding through the vacuum electron beam or argon arc after segmentation machining.Actually weld is not always very smooth after weld,weld reinforcement is not consistent.In order to ensure the assembly accuracy of internal structure and remove weld surface defects,it is necessary to grind weld reinforcement.Weld grinding high precision and big machining difficulty has become the bottleneck of restricting aerospace key parts manufacturing.It is a challenge for manufacturing technology.This thesis is mainly to meet the requirements of grinding inner deep hole butt weld with high quality and high efficiency,considering the characteristics of unequal height on both sides and existing problems of limited equipment machining ability,over-dependence on the operator experience,low production efficiency,low machining accuracy and low qualification rate,integrated technology of measurement and grinding is put forward.Through theoretical and technical research,in the full understanding of current machining situation of the thin-walled cylindrical part's butt weld and machine tool structural characteristics and development trend of domestic and foreign inner hole grinding equipment,this thesis studies the contents including process flow planning,measurement and construction of the weld profile,machining trajectory planning and NC machining,and weld grinding machine tool is designed,it can provide technical support for China's aviation industry manufacturing level and improve the ability of industrialization.The specific research contents are as follows:(1)Weld profile construction and target trajectory generation methodFrom the perspective of measurement and grinding,considering the profile of thin-walled cylindrical part's butt weld is unknown and weld original shape is complex,the method of measurement by the non-contact laser is proposed,and measurement and construction of weld profile,target profile design and machining trajectory generation technology are studied.(2)Weld grinding machine tool structural designFrom the perspective of structural design,combined with the thin-walled cylindrical parts butt weld grinding technology at home and abroad and the characteristics of the inner hole grinding machine tool,the weld grinding machine tool is designed.(3)Weld grinding machine tool control system designFrom the perspective of weld measurement-grinding integrated system,combined with actual demands for weld measurement-grinding integrated system,measurement unit and control unit integration(communication),machine tool coordinate and system parameters setting,weld machining process flow planning and the system hardware and software design are studied.(4)Weld grinding machine tool experimental verificationFrom the perspective of experiment,aimed at the problems of the thin-walled cylindrical parts inner butt weld machining difficult and producing uncontrollable size after machining,a series of experiments are made in the weld grinding machine tool.