大型焊接结构残余应力测试及振动消除

Measurement of residual stress in big weldment and vibraticn stress relieving

为了满足实际工程应用的需要,提高大型焊接结构——1.6m^3反铲挖掘机动臂的工艺及使用性能、节约能源,对其工作的危险截面进行了残余应力测定,并找到了合适的规范,进行振动消除残余应力,此外.在对动臂振动以前,还对小试板进行了振动.结果表明,动臂中存在着较高的残余应力,振动可以消除残余应力,且对稳定结构尺寸有好处。本文还对振动消除残余应力的机理及振动与疲劳的关系进行了初步研究.

This thesis is written for the actual cnginecring work of a big weldment, the boom of 1.6m backhoc excavator,to improve technology and performance and save energy. The distribution of residual stress of the dangerous sections in the boom has been found.Proper specifications for reducing thc residual stress of the boom by vibration have also becn ascertained. Mcreover, befere vibrating the boom, a preliminary vibration experiment was made on a small test plate. The results show that there is high level residual stress in the boom, and this residual stress can be eliminated by vibration.And so the dimensional stability is improved. Besides,exploratory researches were made on the mechanism of residual stress relieving by vibration and on the relationship between vibration and fatigue.