摘要我国正处在经济发展的高峰期,经济建设迅速发展,随之带动了基础建设的脚步,使得社会对起重机械的需求很大,对其安全性、经济性能等方面的要求越来越高。汽车起重机属于臂架类型的起重机,机动性能很强,被广泛应用于各种工程中。本课题主要研究100T重型汽车起重机。由于现在使用的起重机吊臂结构并未达到最优结果,材料也并未被充分利用,所以仍需要改进。在本次设计中,利用现代设计方法---有限元法,对吊臂结构进行有限元分析,来改进吊臂的结构,从而达到最优结构。37723
本次设计首先对臂架的工况和受力情况进行了分析,确定了起重机总体结构参数和材料:设计了臂架的组成部分和几何尺寸:通过对臂架的受力分析确定了其截面的尺寸,并进行了强度和稳定性校核。
本课题对臂架进行了有限元分析。采用PRO/E软件绘制三文实体图,并导入ANSYS软件中,选择实体单元:其材料的密度为7850Kg/m2,杨氏模量为2×1011Pa,泊松比为0.3;网格划分时选择中等密度形式;分别在尾部和液压缸支撑部位添加固定约束,在臂头施加力载荷,侧面加风载。分析结果表明,在二节臂的底部靠近基本臂的区域,应力比较集中,且超出了要求,因此对二节臂增加厚度。对改进后的臂架进行分析得到结果在应力和变形上满足了要求。在结构设计和有限元静力分析的基础上,完成该型起重机相关装配图和主要零件图。 毕业论文关键词:汽车起重机;结构设计;有限元分析
Abstract
Our country is in the peak period of economic development.With the rapid development of economic construction,the government pays more attention to spurring the pace of infrastructure. the demand for heavy machinery in China is great,which makes the requirements of the safety and the economic performance higher and higher. Truck crane belongs to the boom type of crane and it’s mobile performance is very strong.which is widely used in various projects. This thesis mainly studies 100T heavy truck crane. As the crane boom structure is not the best result and the material is not used well, it still needs to be improved.. In this design, by the use of modern design method --- finite element method, the structure of the boom is analyzed to improve the structure of the boom and achieve the optimal structure.
First, I analyze the arm frame of working condition and force situation to identify crane parameters and material of the overall structure ;I design the arm part and the geometric size; By analyzing force of the arm, I determine the size of the cross section of the arm frame and check the strength and stability .
In the design,the finite element analysis of the boom is carried out. Three-dimensional solid map draw by Use PRO/E software is imported to ANSYS software .I select the entity unit:
The material has the material density for 7850Kg/m2, Young's modulus for 2×1011Pa and Poisson's ratio of 0.3; mesh selection of medium density form; respectively in the tail and hydraulic cylinder supporting parts to add fixed constraint, in the brachiocephalic applied load, and in side wind load. The results show that the stress concentration of the second arms is more concentrated than the requirements of the material. So the thickness of the second arms is increased. The analysis of the improved arm frame can meet the requirements in the stress and deformation. Based on the structural design and finite element analysis, the assembly drawings and the main parts of the crane are completed.
Keywords:truck crane;structure design;finite element analysis
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