具有超起装置的起重机伸缩臂稳定性研究

发布时间：2018-03-11 04:23

本文选题：全地面起重机　切入点：超起装置　出处：《大连理工大学》2012年硕士论文　论文类型：学位论文

【摘要】：随着工程建设的快速发展,全地面起重机得到了广泛应用。为了提高起重机的起重性能,伸缩臂长度越来越长并且质量越来越大,但其刚度和稳定性问题却日显突出。全地面起重机超起装置从改善伸缩臂受力状态来大幅提高起重机的起重性能并可以大大减小伸缩臂的挠度、增强伸缩臂的稳定性。目前,国内设计人员对伸缩臂整体稳定性校核主要参考起重机设计规范,但增加超起装置后,伸缩臂系统的受力发生改变,尚没有可参照的具有超起装置的伸缩臂失稳临界力的计算方法。针对上述问题,本文深入分析具有超起装置的伸缩臂系统的结构特点,从挠度微分方程出发,实现伸缩臂稳定性的计算。以500t全地面起重机为例对伸缩臂整体稳定性进行研究,找出伸缩臂在安装超起装置前后所能承受的失稳临界力和超起装置各构件参数对伸缩臂稳定性的影响,并用有限元方法加以验证。主要的工作和研究内容如下： (1)研究具有超起装置的伸缩臂系统力学模型的简化方法并建立模型。用静力法对该力学模型进行稳定性分析计算,推导由超起拉索决定的长度系数,并由此给出了伸缩臂系统的失稳临界力表达式。 (2)以500t全地面起重机为例,计算不同工况下伸缩臂系统所能承受的失稳临界力；简化具有超起装置的伸缩臂系统有限元模型,用有限元分析软件ANSYS求解伸缩臂系统的失稳临界力,验证求解结果的正确性。 (3)在伸缩臂同一臂长不同幅度下,分别改变超起装置各构件参数(包括超起撑杆长度、超起撑杆与伸缩臂在变幅平面内的夹角、超起撑杆安装位置与臂架根铰点的距离),绘制伸缩臂的失稳临界力随各参数的变化曲线,找出各参数的最优值或变化规律,并与实际设计中该参数的取值进行比较分析,为实际设计提供参考。研究表明本文推导的临界力表达式有足够的计算分析精度,可应用于工程设计；且同一工况下伸缩臂在增加超起装置后其失稳临界力明显增大。研究结果不但从理论上说明了超起装置对伸缩臂整体稳定性的影响,同时也为设计超起装置各构件的参数提供了理论依据。
[Abstract]:With the rapid development of engineering construction, all-ground crane has been widely used. However, the stiffness and stability problems are becoming more and more serious. The overloading device of all-ground crane can greatly improve the crane's lifting performance by improving the stress state of the telescopic boom, and can greatly reduce the deflection of the telescopic boom and enhance the stability of the telescopic arm. Domestic designers check the overall stability of the telescopic boom by referring to the design code of the crane, but the force of the telescopic boom system changes with the addition of an overloading device. There is no reference method for calculating the critical force of buckling of telescopic arm with overhoisting device. In view of the above problems, this paper analyzes the structural characteristics of telescopic arm system with overloading device, and starts from the deflection differential equation. Calculation of stability of telescopic boom is realized. Taking 500t all-ground crane as an example, the overall stability of telescopic boom is studied. This paper finds out the influence of the critical force of buckling on the stability of the telescopic boom before and after the installation of the over-lifting device and the parameters of each component of the over-hoisting device, and verifies it with the finite element method. The main work and research contents are as follows:. 1) the simplified method of mechanical model of telescopic arm system with overhoisting device is studied and the model is established. The stability of the mechanical model is analyzed and calculated by static method, and the length coefficient determined by overloading cable is deduced. The expression of the instability critical force of the telescopic arm system is given. (2) taking 500t all-ground crane as an example, the buckling critical force of telescopic boom system under different working conditions is calculated, and the finite element model of telescopic boom system with overloading device is simplified. The finite element analysis software ANSYS is used to solve the instability critical force of the telescopic arm system, which verifies the correctness of the solution. (3) under different amplitude of the same arm length of the telescopic arm, the parameters of each component of the overloading device (including the length of the overloaded brace and the angle between the overloaded brace and the telescopic arm in the amplitude plane) are changed respectively, The distance between the mounting position of the brace and the hinge point of the arm is overtaken, the curve of the critical force of instability of the telescopic arm with each parameter is drawn, the optimum value or the law of variation of each parameter is found out, and the value of the parameter is compared with that of the actual design. It provides reference for actual design. The research shows that the expression of critical force derived in this paper has enough calculation accuracy and can be used in engineering design. Under the same working condition, the critical force of instability of the telescopic boom increases obviously after increasing the overhoisting device. The research results not only explain the influence of the overhoisting device on the overall stability of the telescopic arm, but also increase the stability of the telescopic arm in the same working condition. At the same time, it also provides the theoretical basis for the design of the parameters of each component of the overloading device.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH21

【引证文献】