摘要
变压器油箱箱体遍布焊缝,在振动工况下,油箱疲劳破坏常发生于角焊缝内部缺陷位置处。为分析角焊缝缺陷对变压器油箱疲劳寿命影响,建立了变压器油箱箱体有限元模型,根据油箱振动测试数据在nCode软件中对油箱整箱侧壁角焊缝进行疲劳分析,得到无缺陷情况下变压器油箱整箱侧壁角焊缝的疲劳寿命。取整箱侧壁角焊缝疲劳最危险角焊缝,进一步建立局部含缺陷角焊缝模型,分析含气孔、夹渣缺陷时变压器油箱角焊缝的疲劳寿命的影响规律。最终发现:对于夹渣缺陷,夹渣弹性模量与焊缝弹性模量相差越大,越容易造成疲劳破坏,且软夹渣较硬夹渣更为危险;气孔缺陷尺寸的增大会造成疲劳寿命的减少,而气孔位置越靠近焊根,疲劳寿命越小;且气孔缺陷较夹渣缺陷更容易造成疲劳破坏。
The tank body of the transformer is filled with welds. Under vibration conditions, the fatigue damage of the tank often occurs at the internal defect position of the fillet weld. In order to analyze the effect of fillet weld defects on the fatigue life of the transformer tank, a finite element model of the transformer tank is established. According to the tank vibration test data, the fatigue analysis of the fillet welds on the sidewall of the tank was carried out in the nCode software, and the fatigue life of the fillet weld on the side wall of the lower transformer tank and the defect-free condition was obtained. Take the most dangerous fillet weld of the full tank sidewall fillet weld, and further establish a fillet weld model with partial defects, and analyze the influence law of the fatigue life of the fillet weld of the transformer tank when there are pores and slag defects. It was finally found that for slag inclusion defects, the greater the difference between the slag elastic modulus and the weld elastic modulus, the more likely it is to cause fatigue damage, and soft slag inclusions are more dangerous than hard slag inclusions;the increase in the size of pore defects will cause fatigue life reduce, the closer the pores is to the welding root, the shorter the fatigue life will be;and the pore defects are more likely to cause fatigue damage than the slag inclusion defects.
作者
陈奔
嵇玉辰
梁一恒
王晓笋
CHEN Ben;JI YuChen;LIANG YiHeng;WANG XiaoSun(School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China)
出处
《机械强度》
CAS
CSCD
北大核心
2023年第1期209-217,共9页
Journal of Mechanical Strength
基金
国家电网有限公司科技项目(SGZJ0000KXJS1800302)资助。
关键词
变压器油箱
角焊缝
焊接缺陷
疲劳寿命
Transformer oil tank
Fillet weld
Welding defects
Fatigue life
作者简介
陈奔,男,1997年生,江苏南通人,汉族,武汉大学动力与机械学院硕士,主要从事数值仿真分析和金属焊接疲劳方面的研究;通信作者:王晓笋,男,1979年生,安徽怀宁人,汉族,武汉大学动力与机械学院教授,博士生导师,主要研究方向为机电传动与智能控制,机械摩擦与磨损研究。E-mail:wxs@whu.edu.cn。
