摘要
针对铸造起重机服役过程中金属结构安全性问题,提出从疲劳破坏的角度分析其裂纹扩展情况。以铸造起重机金属结构为研究对象,调研分析铸造起重机的工艺流程,结合金属结构理论和雨流计数法,得到一年内主梁危险点的两参数二维应力谱,根据线弹性断裂力学,应用Paris公式对裂纹扩展情况进行预测,根据疲劳裂纹扩展尺寸进行预测相对应的疲劳剩余寿命。以此为基础,通过Msc.Fatigue仿真软件模拟裂纹扩展增长趋势,从而预测焊接箱形梁结构的疲劳剩余寿命。以100/40t-28.5m四梁偏轨铸造起重机焊接箱形梁结构为例,其理论计算结果与仿真结果的相对误差为1.44%。结果表明:通过理论与仿真相结合的方式可较为准确的分析疲劳裂纹扩展情形,确保了疲劳剩余寿命计算结果的精确性。
In view of the safety of metal structure during the service of casting crane,the crack growth is analyzed from the angle of fatigue failure. The casting crane metal structure as the research object,research and analysis of the process of casting crane,metal structure theory and combined with the rain flow counting method,get the two parameter two-dimensional stress spectrum of the dangerous point of girder in one year. According to the linear elastic fracture mechanics,the Paris formula is applied to predict the crack growth. According to the size of fatigue crack growth,the corresponding fatigue remaining life is predicted. Based on this,the Msc. Fatigue simulation software is used to simulate the growth trend of crack growth,so as to predict the fatigue life of the welded box beam structure. Taking the welded box beam structure of 100/40 t-28.5 m four beam partial rail casting crane as an example,the relative error between the theoretical calculation results and the simulation results is 1.44%. The results show that the fatigue crack growth situation can be accurately analyzed through the combination of theory and simulation,which ensures the accuracy of fatigue residual life calculation results.
作者
徐格宁
张永才
张魏唯
XU Ge-ning;ZHANG Yong-cai;ZHANG Wei-wei(School of Mechanical Engineering,Taiyuan University of Science and Technology,Shanxi Taiyuan030024,China)
出处
《机械设计与制造》
北大核心
2020年第3期13-17,共5页
Machinery Design & Manufacture
基金
起重机械技术委员委员会国家标准《铸造起重机报废条件》研制(20160514-T-604)。
