Development And Quality Control Of Welding Fixture For Hood Inner Panel Assembly

Body-in-white welding fixtures are important parts of the welding process.The design and manufacturing level of welding fixtures directly affects the entire body-inwhite welding process development cycle,body quality,and production efficiency.This dissertation takes the development and quality control of the welding fixture of the engine hood inner panel assembly in the welding workshop of NAVECO as the subject.The digital three-dimensional design of the welding fixture of the engine hood inner panel assembly is carried out,and the stress is based on HyperWorks software.Researches on simulation analysis,interference inspection of welding fixtures based on CATIA V5 software and motion process simulation,application of quality control based on SPC technology,etc.The main research contents and results are as follows:(1)The design requirements,design methods and evaluation basis of welding fixtures in actual production are expounded.The six-point positioning principle,the“N-2-1” positioning theory of sheet metal parts,and the “RPS” positioning reference theory of automotive fixtures are discussed in detail for follow-up research.The development laid a theoretical foundation.(2)CATIA V5 software was used for the welding fixture of the hood inner panel assembly,combined with the product structure,material characteristics,production process,production program,RPS positioning points and other information of the hood inner panel assembly(workpiece to be welded)The positioning pin component design,positioning fixture component design,fixture substrate base design and clamp specific structure design were obtained,and the three-dimensional numerical model of the fixture was obtained;then,the work piece was subjected to the force under the force of gravity and the welding clamp using the Optistruct module of HyperWorks finite element analysis software analysis,simulation results show that the maximum deformation of the workpiece meets the requirements of the drawing;then used the DMU module of CATIA V5 software for interference inspection and simulation analysis of the movement process,the results show that the fixture components do not interfere with the workpiece and the welding clamp;finally,the inner plate assembly welding fixture design of the pneumatic control system and production cycle calculation of the welding fixture to the inner panel assembly were carried out.The above development process fully proves that CAD/ CAE technology has important guiding significance for the successful development of welding fixtures.(3)Manufactured welding fixtures for the hood inner panel assembly,and in order to verify that the welding fixtures meet the quality requirements of compliance,repeatability,and consistency,the welding fixtures were debugged in eight steps;combined with SPC technology,25 groups 125 data were calculated and analyzed.The analysis results show that the current hood assembly is stable,which proves that the fixture design is reasonable.Finally,the quality problems encountered in the welding production process were analyzed and discussed in conjunction with the actual production,and a solution is provided.The research in this dissertation has important guiding significance for the design,manufacture and quality control of welding fixtures.The method used in the research has important reference value for the development of other projects.