【作者】 张骞；

【导师】 叶辉； 李婷婷；

【作者基本信息】 吉林大学 ， 工程硕士（专业学位）， 2017， 硕士

【摘要】 随着汽车工业发展,各车企逐渐完善开发流程,同步工程应运而生。同步工程是在汽车设计的同时,将汽车制造工艺也设计出来,避免后期产生设计变更,降低开发成本,缩短整车开发周期。电泳是车身质量的重要指标,是涂装同步工程的重点。工程师主要根据经验对电泳工艺进行分析,但由于主观性较强,经常会出现纰漏。ECoat Master仿真软件专业应用于电泳仿真分析,采用有限元仿真技术,模拟白车身电泳工艺。通过分析仿真结果,能够评估白车身电泳效果,优化和验证工艺设计方案。ECoat Master具有精度高、操作简单等优点,经过大众、奥迪、通用、戴姆勒(奔驰)等汽车厂家的应用,已经被证明适合汽车行业电泳工艺设计。本文基于ECoat Master辅助同步工程分析,通过对车身数据仿真计算,找出电泳膜厚不足区域,提出优化方案。再结合样车电泳剖解,验证仿真结果与实测膜厚是否吻合,确保车身结构满足电泳工艺要求。本文从以下几方面论述:一、仿真对标。收集生产线工艺参数和设备参数,包括电压,温度,电泳时间,车身运行速度,槽体尺寸,电极尺寸和电极数量等。在涂料供应商的实验室内测定涂料参数,采集膜厚和电流随电压、转速变化的数据,建立涂料数据库,导入ECoat Master。建立电泳槽模型和车身运行轨迹。将量产车型车身数据转换为STL格式后导入ECoat Master。自动划分网格,进行仿真计算。将量产车型电泳剖解结果与仿真结果对比,确认仿真计算的可靠性。对于ECoat Master软件和算法存在的偏差,需要软件工程师进行耦合处理和修正,更新涂料数据库,使仿真结果与实际相当。二、同步工程。根据《电泳涂装车身设计规范(指南)》,分析电泳工艺成膜性,主要从泳透力孔、排气孔和排液孔三个方面分析。在门槛、立柱、轮罩、侧围上框等区域找出合适的开孔位置,提出开孔建议,与车身设计人员讨论更改方案,同时保证满足强度、刚度和NVH等性能。确定新车型计算数据,应用ECoat Master进行仿真计算。三、结合仿真结果,对电泳膜厚不足的区域提出优化方案,提交设计变更需求并跟踪进度,确保在数据冻结前更改完成。四、电泳车身剖解。样车制造完成后电泳剖解,将车身和闭合件的外板全部剥离,测量内外板和各腔体膜厚,生成剖解报告。比对实测膜厚值和仿真结果,确认电泳设计优化方案有效性。更多还原

【Abstract】 With the rapid development of auto industry,companies have gradually perfected development process,Simultaneous Engineering arises at the right moment.Simultaneous Engineering is to design manufacturing process during body designing,avoid design alternation,help cut down costs,shorten the period of development.ED effect is an important target of quality of BIW,which is also one main task of Simultaneous Engineering.Engineers used to analyze ED process by experience.However,there always were mistakes due to analyzing subjectively by experience.ECoat Master software is a professional software for ED simulation.It based on finite element simulation technique,can simulate the process of ED.Because of the results of simulation,it can evaluate the ED effect of BIW,optimize and prove the possibility of process plans.ECoat Master have advantages like high precision and easy operation.ECoat Master is widely applied by VW,Audi,GM,Benz and other auto companies and it has been proved to be appropriate for ED process planning in auto industry.This article based on ECoat Master,calculates data of body in white and checks areas with ED infects.Then give suggestions of improvement.After that,with anatomy of prototype vehicles,check whether the results could match measuring data,make sure the design can reach the goal of ED process.This article will mainly discuss in several aspects:firstly,benchmarking.Collect parameters of process and parameters of equipment.In supplier’s laboratory,measure the parameter of coating,collect the data of thickness varying with voltage and speed of revolution.Set up database of coat.Put them into ECoat Master for analyzing.Build up the model of ED booth and path.Turn the data of producing vehicle into STL form.Put these data into ECoat Master.After automatically meshing,it comes to calculation,then compared the anatomical results with calculated results.Confirm the feasibility.Considering the deviation of software and calculation,we need software engineers to do amendment and improvement,update paint data and make sure that simulation results fit to actual situation.Secondly,Simultaneous Engineering.Refer to 《ED coat designing specification of car body》,evaluate probability of ED effect mainly about throwing power,venting ability and draining ability.Find out appropriate holes on different areas of body.Suggest adding ED holes and discuss modification plans with designers.Make sure that it can fulfill the requirement of intensity,rigidity,NVH and sealing.As soon as having the data for CAE,use ECoat Master to calculate.Thirdly,compare with the simulated result,offer optimized advices on adding ED holes and modification of structure.Feed back ECR and follow the schedule of optimized plans.Make sure the data has been corrected before it’s frozen.Finally,ED anatomy of prototype car.After anatomy,we measure the ED thickness and compare the data with calculated results,then confirm the validity of optimized scheme.更多还原