面向轻量化目标的起重机伸臂结构设计及截面尺寸优化

Crane jib structure design and section dimension optimization for lightweight target

为满足工程上对大吨位和小质量起重机的追求,实现起重机伸臂轻量化设计目标,在QY25K5型起重机伸臂主要结构参数尺寸的基础上,通过UG软件对伸臂进行了数字化设计,建立了CAD模型。根据GB/T 3811—2008,确定了在典型危险工况下,伸臂的工作载荷、许用应力及许用挠度,并对伸臂的强度、刚度及1阶屈曲模态进行仿真分析。根据分析结果,以伸臂截面尺寸作为优化设计变量,分别通过Inspire和ANSYS软件对伸臂上盖板和腹板厚度进行尺寸优化,得到两组板厚优化值;根据起重机设计标准及工程上常用的钢板厚度确定了上盖板和腹板的厚度,生成伸臂的轻量化设计方案,减重率可达15.2%。对伸臂力学性能进行校核,结果表明:设计方案在符合起重机典型危险工况下,满足强度、刚度及稳定性的要求,达到减重的目的。综合两种优化方案优化的方法,可为起重机伸臂轻量化设计提供参考。

In order to meet the pursuit of large tonnage and small quality crane in engineering,and realize the lightweight design goal of crane jib,a digital design of jib was performed using UG software and CAD model on the basis of main structural parameters of QY25K5 crane jib.According to GB/T 3811—2008,the working load,allowable stress and allowable deflection of the jib were determined under the typical dangerous occasion.The strength,stiffness and first order buckling mode of the jib were simulated and analyzed.According to the analysis results,taking the dimension of the jib section as the optimal design variable,the thickness of the upper cover plate and the lower web of the jib were optimized using Inspire and ANSYS software,respectively.Two groups of plate thickness optimization values were obtained.The lightweight design scheme of jib was generated according to the crane design standard and the thickness of the steel plate commonly used in engineering.The weight reduction rate could reach up to 15.2%.The mechanical performance of the jib was checked.The results showed that the design scheme met the requirements of strength,stiffness and stability under the typical dangerous working conditions of the crane,and achieved the goal of weight loss.The optimization methods of two optimization schemes were integrated to provide references for the lightweight design of the crane arm.