Motor For Pumping The Dynamic Characteristics Of The Structure Analysis And Parameter Optimization Design

The dynamic characteristic analysis of structural systems has increasingly studied in structural dynamics field, and it has been regarded as one of the important direction to development by occidental developed countries. This paper is based on the engineering research on complex structures of the motor-reversing type pumping unit. The pumping unit is mainly made up of driving members, support members. Of course, it's very important to ensure the driving members work reliably and stably. But it is the bracket that supports them, so, the reliability and stability of the bracket affect the whole pumping unit directly. This paper systematically makes the dynamic characteristic analysis and experimental verification of the bracket, and establishes a foundation on the dynamic response calculation, the dynamic characteristic analysis of the bracket and optimization in structural designing step by step. This work also finds a way for the improvement of the bracket simultaneously.This paper summarizes researches on dynamic characteristic analysis at home and abroad at first. And then, based on the modal analysis theory, it analyzes the component and working situation of the motor-reversing type pumping unit, considers improving accuracy and reducing calculational scale to a lower rank synthetically, then makes calculational model of the bracket with Finite Element Method (FEM) applied. In this paper, the model is made as a special truss work with beam element and link element used together to disperse the bracket. Then the static analysis, modal analysis and response to impact load are all made in this paper. And influence to mode produced by different structural parameters and material is discussed in the paper too. This paper also analyses another kind of pumping unit which influenced deeply by impact load, and discusses the relation among the magnitude of impact load, acting time and the maximum displacement of the bracket.The result forenamed shows that he safety margins of static strength and stiffness are excessive. According to this, this paper takes size of sections as design variables, maximum displacements of nodes, maximum stress of members and range of sections' size as constraint conditions, and minimum weight of bracket as object function, then makes optimization designing about the structural parameters of the bracket. In the end,this paper makes analysis again on the bracket after optimization designing, and draws a conclusion that the modified bracket can satisfy the working requirement and result in a reduction in weight and cost.The dynamic characteristic analysis of structures is required to describe the structural systems accurately, and FEM is often used to make theoretical calculation models in engineering. FEM applies discretization theory, that is, the continuous system is dispersed into a discrete system with interdependence in a node. Through the hypothesis of the structural material and shape, the simplification of the structural constraints and joints, the theoretical calculation model is made with finite element techniques. And because of the hypothesis and simplification, the calculation model gets error about structure, orders and parameters of itself. So, it needs tests to verify whether the precision of calculation results is reliable. According to this, the paper analyzes the process and principles of modal test and stress strain test, and brings forward ideas and methods about structural modal test. But owning to the limit of test conditions, the modal test hasn't been executed.