摘要
疲劳破坏是桥式起重机主要的失效形式之一。针对桥式起重机金属结构的疲劳问题,以某厂额定起重量为50 t、跨度为28 m的双粱桥式起重机为研究对象,通过有限元分析,对其强度进行校核,并得到疲劳源附近的应力值。基于有限元分析,应用断裂力学方法估算桥式起重机的剩余疲劳寿命,结果表明,当起重机裂纹长度超过20 mm时,裂纹的扩展速率明显加快。该方法简便实用,不仅可以估算焊接结构的剩余疲劳寿命,而且可以推算出具有初始缺陷的焊接结构裂纹扩展任一阶段时的疲劳寿命。对于预防疲劳破坏事故的发生具有重要的意义。
Fatigue failure is one of the main failure forms of bridge cranes. Aiming at the fatigue problem of the metal structure of the bridge crane,the double beam bridge crane with rated lifting weight of 50 t and span of 28 m was taken as the research object and a finite element analysis of the bridge crane was made. Through finite element analysis, its strength was checked, and the stress value near the fatigue source was obtained. The residual fatigue life of bridge crane is estimated by fracture mechanics method based on finite element analysis, which shows that when the crack length of crane exceeds 20 mm, the crack growth rate accelerates obviously. This method is simple and practical, which can not only estimate the residual fatigue life of welded structures, but also calculate the fatigue life of welded structures with initial defects at any stage of crack growth. It is of great significance to prevent fatigue damage accidents.
作者
柳柏魁
LIU Bokui(Fujian Special Equipment Inspection Institute Zhangzhou Branch,Zhangzhou,Fujian 363000,China)
出处
《机电工程技术》
2019年第12期273-275,共3页
Mechanical & Electrical Engineering Technology
关键词
桥式起重机
有限元分析
疲劳寿命
bridge crane
finite element analysis
fatigue life
