截面尺寸对伸缩臂屈曲失稳性能的影响

Influence of section size on buckling stability of telescopic boom

伸缩臂作为起重机的主要承载受力构件,其设计是否合理,直接影响整机的起重性能与安全.伸缩臂架为典型的薄壁板壳结构,破坏形式主要以发生屈曲导致承载能力下降,甚至发生安全事故.为满足起升重量和起升高度,保证伸缩臂的稳定性,已成为设计者需主要解决的问题.影响伸缩臂屈曲临界载荷的因素很多,包括支撑方式、截面惯性矩、长度以及材料等,而当支撑方式、材料、长度确定时,对屈曲临界载荷影响最大的因素是截面惯性矩.通过分析截面尺寸对截面惯性矩的影响,进而可以分析出截面尺寸对伸缩臂屈曲临界载荷的影响.针对伸缩臂抗屈曲失稳能力,采用理论结合有限单元分析法,以U型截面为例,分析了截面尺寸对伸缩臂屈曲失稳性能的影响,为设计者提供了一定的设计参考依据.采用合理的截面尺寸,提高了伸缩臂的抗屈曲能力.其他形式截面可借鉴同样的方法进行分析.

The telescopic boom is the main bearing force component of the crane.The rationality of the design will directly affect the performance of the machine and safety.The telescopic boom is a typical thin-walled plate and shell structure.Its main form of damage is the occurrence of buckling,resulting in decreased carrying capacity,or even a security incident.In order to meet the lifting weight and lifting height,to ensure the stability of the telescopic boom has become a major problem for the designer.There are many factors that affect the critical load of the telescopic boom,including the support method,the inertia moment,the length and the material.When the support mode,material and length are determined,the maximum factor affecting the buckling critical load is the inertia moment.By analyzing the influence of section size on the inertia moment of section,the influence of cross section size on buckling critical load of telescopic boom can be analyzed.In this paper,the influence of the cross-section size on the buckling instability of the telescopic boom is analyzed by combining theory with the finite element analysis method,taking the U-section as an example.The results of the analysis can provide designers with design reference basis,in order to use a reasonable cross-sectional size,to improve the flexural capacity of telescopic boom.Other forms of cross section can be analyzed using the same method.