1、坡口间的焊接残余应力坡口间距对应的影响也较为明显，从表中可以看出，坡口间距越大，应力值也有明显的增大，最大间隙处应力值（为最小间隙处应力值的 3.5 倍左右） 。从理论上分析，坡口越大，需填充的金属越多，焊接时热作用时间越长，温度也越高，因而产生更大的应力。Corresponding are relatively obvious, the influence of groove spacing can be seen from the table, the groove spacing, the greater the stress value had increased obviously,
2、 the biggest gap in stress value (for minimum clearance stress value of about 3.5 times). Theoretically analysis, groove, the greater the need to fill the more metal, welding thermal effect when the longer the time, the higher the temperature, and thus have a greater stress. 4.3 坡口间距对机械性能的影响4.3 groo
3、ve spacing effect on the mechanical properties http:/ http:/ http:/ http:/可以看出，坡口间距对机械性能的影响较小，但坡口间距对缺陷有较大的影响。两个试样都做了宏观金相检查，坡口间距越小，未焊透缺陷倾向增加。所以，坡口间距间接地影响了焊接接头的强度，降低疲劳强度。It can be seen that groove spacing have less effect on the mechanical properties, but the groove spacing has a larger effect on defe
4、cts. Two samples have macro metallographic examination, groove spacing is smaller, lack of penetration defects tend to rise. So, groove spacing indirectly affect the strength of welding joint, reduce fatigue strength. 5 金相分析5 metallographic analysis 在相应的最大坡口端和最小坡口端，分别取试样进行金相分析，对比母材金相，组织变化差异很小。可见，因所用
5、材料为普通碳素结构钢（管板和筒体材料都选用了 Q235-B） ， 土工格栅厂家这类材料的组织在加热时，长大倾向并不明显。可以认为，坡口间距对焊接接头及热影响区金属组织的影响是不大的。或者说，因焊接接头及热影响区金属组织所引起的焊接接头失效现象的因素要比焊接缺陷和应力变化所产生的影响小得多。In the corresponding the most slopes end and minimum groove end mouth, samples were taken for metallographic analysis, contrast material metallographic, sm
6、all differences in organizational change. Visible, because the materials used for ordinary carbon structural steel (tube plate and the cylinder the Q235 material selection are - B), the organization of this kind of material when heated, grew up tendency is not obvious. Can think, groove spacing on t
7、he influence of the weld and heat affected zone metal group is not big. Or, because of the weld and heat affected zone metal organization caused by the welding joint failure factors than welding defects and the impact of stress changes little. http:/ http:/ http:/ http:/6 结论6 the conclusion 通过以上分析，造
8、成管板与壳体连接焊接接头失效的重要因素中，坡口尺寸大小是其中之一。因为坡口尺寸大小对焊接接头内部缺陷的产生及热影响区的焊接残余应力大小有着重大的影响，坡口越大，焊接缺陷产生的可能性增加，焊接残余应力增加。在焊接实践中，可以通过选择合适的坡口尺寸， 酿酒设备配以合理的焊接工艺参数，尽可能降低焊接接头及热影响区的焊接残余应力，则可以减少此类失效现象的发生，从而减小生产中的经济损失。Through the above analysis, resulting in the tube sheet and shell connection weld failure of important factors
9、, the groove size is one of them. Because the groove size of internal defects of welding joint and the welding residual stress of heat affected zone size has a significant impact, the groove, the greater the possibility of welding defects, welding residual stress is added. In welding practice, can choose the right groove size, with reasonable welding process parameters, as far as possible reduce the welding residual stress of weld and heat affected zone, and can reduce the failure phenomenon, so as to reduce the economic losses in production.
