回转支承承载性能分析方法研究

发布时间：2018-01-19 11:23

本文关键词： 回转支承刚度特性高强螺栓承载性能　出处：《大连理工大学》2011年硕士论文　论文类型：学位论文

【摘要】：随着国民经济的迅速发展,起重、挖掘等设备日渐轻量化,主机结构越来越紧凑,承载能力越来越高,回转支承作为重要组成部件,人们对它的设计要求也越来越高。近来一些回转支承按接触应力计算满足使用要求,但在使用过程中经常出现卡死、滚道压陷、压裂等非正常失效现象。除部分是由于制造质量外,另外两个重要原因就是回转支承刚度不足和高强螺栓连接失效。目前,国内回转支承刚度分析通常只注重滚动体与滚道之间的局部接触变形而忽略滚圈自身变形对刚度的影响,导致整体变形量计算不够精确；高强螺栓连接结构中存在着摩擦、接触、外载荷偏心、螺栓自身弯曲等特点,导致设计人员在对其进行计算时多基于一定的简化,将螺栓连接结构理想化。针对以上问题,本文充分研究回转支承的结构和受力特点,深入研究回转支承刚度分析方法和高强螺栓计算方法,以弥补当前回转支承承载性能分析方法中的不足。论文的主要研究工作和研究成果如下： (1)分析回转支承结构特点、工作原理和研究现状,研究当前回转支承承载性能计算方法中存在的问题,确定刚度分析方法和高强螺栓计算方法研究的必要性和可行性； (2)以交叉滚子式回转支承为主要研究对象,详细分析其工作原理；采用载荷叠加法计算其滚道圆周上的正压力,推导出回转支承在轴向载荷单独作用下、倾覆力矩单独作用下以及轴向载荷和倾覆力矩耦合作用下滚道圆周单位弧长上的正压力； (3)基于Hertz接触理论和ANSYS软件,建立了能够考虑回转支承滚圈自身变形的计算内、外圈相对位移的有限元模型。通过有限元计算得到了回转支承轴向载荷与变形之间的关系、倾覆力矩与变形之间的关系,并对倾覆力矩作用下滚道圆周上的变形分布情况进行了分析,将计算结果与现有结论进行比较,说明有限元计算结果的可靠性； (4)通过合理的假设,并综合考虑摩擦、接触、外载荷偏心、螺栓自身弯曲等所引起的各种非线性,建立能够反映回转支承用高强螺栓连接性能的三维有限元模型,得到其静强度、疲劳强度及相关应力的有限元计算方法。通过实例分析,对有限元算法和解析算法的计算结果进行比较,说明有限元算法的准确性； (5)应用回转支承用高强螺栓的有限元算法进行数值试验,研究预紧强度、连接基座板厚以及套筒高度对螺栓连接性能的影响及影响程度。其成果将有效地指导工程设计人员准确完成回转支承设计,并且其研究思想也可应用到对其它设备上的螺栓连接处。
[Abstract]:With the rapid development of the national economy, lifting, mining and other equipment increasingly lightweight, the structure of the mainframe is becoming more and more compact, the bearing capacity is becoming higher and higher, and the slewing bearing is an important component. Recently, some slewing bearings meet the requirements according to the contact stress, but in the process of use, they often get stuck and the raceway collapses. In addition to the manufacturing quality, the other two important reasons are the insufficient stiffness of the slewing support and the failure of the high strength bolt connection. At present, the analysis of the stiffness of the rotary bearing in China only pays attention to the local contact deformation between the rolling body and the raceway, but neglects the influence of the deformation of the roller itself on the stiffness, which leads to the inaccuracy of the calculation of the total deformation. There are some characteristics in high strength bolt connection structure such as friction contact eccentricity of external load and bending of bolt itself which leads designers to idealize bolt connection structure based on some simplification. In view of the above problems, this paper fully studies the structure and mechanical characteristics of the slewing bearing, the stiffness analysis method of the slewing bearing and the calculation method of the high-strength bolt. The main research work and research results are as follows: 1) the characteristics, working principle and research status of slewing bearing structure are analyzed, and the problems existing in the calculation method of bearing capacity of slewing bearing are studied. The necessity and feasibility of research on stiffness analysis method and high strength bolt calculation method are determined. (2) taking the cross roller rotary bearing as the main research object, the working principle of the bearing is analyzed in detail. The positive pressure on the raceway circumference is calculated by the method of load superposition, and the axial load acting on the slewing bearing is deduced. The positive pressure on the unit arc length of the raceway under the action of overturning torque alone and under the coupling of axial load and overturning moment; 3) based on Hertz contact theory and ANSYS software, a calculation method is established which can take into account the deformation of the roller ring of the slewing bearing. Finite element model of relative displacement of outer ring. The relationship between axial load and deformation of slewing bearing and the relation between overturning moment and deformation are obtained by finite element calculation. The deformation distribution on the raceway circumference under the action of overturning moment is analyzed. The results are compared with the existing conclusions and the reliability of the finite element calculation results is proved. 4) through reasonable assumptions and taking into account all kinds of nonlinearity caused by friction, contact, eccentricity of external load, bending of bolt itself, etc. A three-dimensional finite element model which can reflect the connection performance of high strength bolts for rotary bearing is established. The finite element method for calculating static strength, fatigue strength and related stress is obtained. The results of finite element algorithm and analytical algorithm are compared to show the accuracy of the finite element algorithm. The finite element method of high strength bolt for rotary support is used to carry out numerical test to study the pretightening strength. The influence and degree of connection base plate thickness and sleeve height on bolt connection performance. The results will effectively guide engineering designers to complete the design of slewing support accurately. And its research ideas can also be applied to bolt connections on other equipment.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH123

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