某汽车车门焊接工艺分析与工装设计（本科毕业论文设计）.doc

摘    要

课题的目的是通过对长安之星II汽车中门焊接生产线现行的工艺及工装夹具进行分析和研究。分析在整个中门生产的工艺流程中，保证车门焊接质量、效率的焊接设备、工装夹具和工艺参数。当这些工艺参数偏离工厂现行工艺的规定值时车门的焊接质量会出现何种缺陷，并提出解决这些缺陷的方案、措施。最终使焊接工艺得到优化，中门的焊接质量得到保证。
在长安之星二代汽车中门的焊接生产过程中，由于电阻焊在薄板焊接方面有着其它焊接工艺难以比拟的优势，并且它易操作，有良好的经济性，焊接工艺成熟可靠，所以电阻焊承担了长安之星II汽车车门的整个焊接过程。所以电阻焊的工艺参数是保证焊接质量的关键。工艺参数包括：焊接时间、焊接电流、预压时间、电极压力、维持时间、休息时间。只有在这些参数在规定的范围内，中门最后的焊接质量的检测中才能合格，减少废品率。文中对规定范围内的焊接参数分析、优化，在保证中门的焊接精度的基础上，提高了电阻焊焊接的可靠性，使得车门的焊接质量得到改善，进而提高生产效率，降低生产成本，使企业具备更强的竞争力。
在车门焊接流水线上，真正用于焊接操作的工作量仅占30%-40%，剩下的60%-70%为辅助和装夹工作。因此夹具在车门焊接过程中起着重要的作用，文中先对中门焊接生产线的工艺布局进行分析，重点对中门内蒙皮在车门焊接过程中的定位夹紧，车门零件之间正确的装配关系进行了分析、研究。选取中门内蒙皮焊接总成16个电阻焊夹具中的7号夹具，分析它的组成结构、夹紧原理及设计过程。包括是如何保证中门在焊接总成的位置，怎样缩短辅助装夹工序的时间和如何确定和计算夹紧力，目的是保证组成中门各焊接零部件的装配位置、焊接精度，平衡工位，降低非生产用时，最终使中门焊接质量得到保证，使企业生产出优异的产品。
 

关键词： 电阻焊，焊接夹具，汽车车门，电阻焊机，点焊

ABSTRACT

The purpose is to subject the Chang'an Star II car door welding production lines in existing technology and fixture for analysis and research. Analysis of the entire production process in the door, ensure that the doors welding quality and efficiency of welding equipment, fixture and technical parameters. When these technical parameters deviate from the provisions of the existing factory at the door of the welding quality of what will appear defects, shortcomings and propose solutions to these programmes and measures. The end, the welding process has been optimized, the welding quality of the door is assured.
  Chang'an Star in the second-generation car door in the welding production process, because of resistance in the welding area plates with other welding process difficult to compare the advantages, and it easy to operate, a good economy, welding technology mature and reliable, so resistance welding Commitment to the Star II Changan Automobile door of the welding process. Therefore, the resistance welding process parameters is the key to guarantee the quality of welding. Technical parameters, including: welding, welding current, time-pressure, the electrode pressure to maintain the time, rest time. Only in these parameters in the scope of the provision, the doors of the welding quality of the final test in order to pass the waste reduction rate. Text of the provisions of the welding parameters analysis, optimization, to ensure accuracy in the door of the welding on the basis of improving the reliability of the resistance welding, making the doors of the welding quality has improved, thus increasing production efficiency, reduce production costs, Enterprises have stronger competitiveness.
  Welding on the door in the pipeline, the real welding operation for the workload of only 30 percent to 40 percent, while the remaining 60 percent supporting and 70 percent for clamping work. Therefore fixture in the process of welding the doors play an important role in the first text on the door in the process of welding production line layout analysis, the focus on the doors of the building skin in the process of welding the positioning clamp, the door between the right of assembly parts relations An analysis of research. Select the skin of the building welding assembly 16 fixture in the resistance welding fixture on the 7th, the composition of its structure, clamping principle and the design process. Including how to ensure that the doors are welded assembly in the location and how to reduce the fixture supporting processes and how to determine the time and calculated clamping force, the purpose is to ensure that all doors in the composition of welding parts of the assembly position, welding precision, the balance - To reduce non-production, in the end, the welding quality be assured that the door to enable enterprises to produce superior products.

 
Key words： Resistance welding，welding fixture，car doors，resistance welding
　　　　　　machine，Spot Welding
 

目   录
中文摘要 Ⅰ
ABSTRACT Ⅱ
1绪论 1
1.1电阻焊的特点及在汽车制造中的运用情况 1
    1.1.1电阻焊的工作原理和特点 1
1.1.2电阻焊在汽车制造中的应用 1
1.2电阻点焊工艺 2
1.2.1电阻焊功率计算 2
1.2.2影响电阻焊质量的工艺参数 2
    1.2.3点焊焊接参数的选取方法 3
1.3电阻焊工装夹具 4
1.3.1焊接夹具在汽车制造中应用情况 4
1.3.2焊接夹具设计要求焊接夹具的组成及结构特点 5
1.3.3焊接夹具设计应该遵循的原则 6
1.3.4焊接夹具设计要求 7
1.3.5焊装夹具的精度控制 7
1.4本课题的意义 8
1.5本课题的主要研究内容 9
  1.6本课题的实现途径 9
2长安之星II汽车中门焊接材料的焊接性分析 10
2.1长安之星II汽车焊接板材的化学成分和性能 10
2.2板材焊接性分析 11
2.3镀锌钢板的特点及在汽车工业中的应用 11
2.4镀锌钢板的电阻点焊研究现状 12
 3长安之星II汽车中门焊接工艺分析、研究及优化 13
 3.1焊接设备的分析与选用 13
 3.1.1焊机 13
 3.1.2焊钳 14
 3.2长安之星II汽车中门现行焊接工艺的分析、研究 15
   3.2.1长安之星II汽车中门内蒙皮焊接零部件 16
   3.2.2长安之星II汽车中门焊接工艺分析 17
 3.3长安之星II汽车中门焊接质量的检测 20
 3.4影响中门焊接质量的主要因素 21
   3.4.1焊接电流 21
   3.4.2焊接压力 21
   3.4.3焊接时间 21
  3.4.4焊件表面情况 21
 3.4.5电极的材质及接触面的形状 22
 3.5保证焊接质量的主要方法 22
 3.6焊接工艺优化 23
 4长安之星II汽车中门焊接夹具在工位中的具体运用 24
 4.1长安之星II汽车车门蒙皮焊接夹具 24
   4.2内蒙皮夹具 26
      4.2.1夹具地板 26
      4.2.2分析夹具的选取 27
      4.2.3组成7号夹具的零部件 28
      4.2.4 7号夹具的设计流程 29
5结论 34
6致谢 35
参考文献 36