| The connecting rod device is the main force and moving parts of the beam pumping unit.It has a harsh working environment,is subjected to complex alternating impact loads,and is relatively weak compared with other components.When there are micro cracks and fractures,it is faulty.Analysis and study of the fault problem and its performance of the linkage device is the focus of pumping unit development and design.Traditional design can not keep up with the development of modern machinery industry.This topic is based on modern design theory,using computer as design tool,based on engineering design related software,combining multi-body dynamics theory,finite element method,fatigue strength theory,optimization design.Methods,etc.,analyze and study the performance of the conventional beam pumping unit linkage.Firstly,this thesis takes the C-456D-305-144 type beam pumping unit as the research object,analyzes and calculates the kinematics and dynamics of the beam pumping unit,and analyzes the suspension point and connecting rod device.The kinematics parameters such as displacement,velocity and acceleration are analyzed,and the dynamic characteristics such as the force of the suspension point and the connecting rod device are analyzed,which provides a reliable theoretical basis for the virtual prototype simulation and finite element simulation analysis below.Secondly,the virtual prototype simulation software ADAMS is used to simulate the kinematics and dynamics of the multi-rigid system and the rigid-flexible coupling system.The kinematics and dynamics parameters of the pumping unit are obtained,and the theoretical analysis is verified.Calculate the correctness of the analysis model of the beam pumping unit established in this paper,provide the original input data for the subsequent finite element analysis,and generate the load-time history file of the linkage device to provide the load condition for the fatigue strength analysis.Thirdly,through the ANSYS Workbench platform simulation,the total deformation,stress distribution,strain distribution and modal vibration characteristics of the connecting rod device considering the weld are obtained,and the nonlinear buckling stability analysis with prestress is obtained.The nonlinear critical buckling instability load of the connecting rod device obtains the first six-order buckling load factor and the buckling mode shape,which provides a theoretical basis for the subsequent structural optimization design,and provides a practical re ference value for the future research of the linkage device.Finally,this paper uses an improved nominal stress method,combined with fatigue strength analysis software to calculate the fatigue life,fatigue damage and safety factor distribution of the linkage device.Based on the above results,the linkage sleeve is the weak component of the linkage device.This in turn provides data support for the following optimized designs.Next,the parameterization modeling of the connecting rod sleeve is carried out.A multi-objective driving optimization method based on Direct Optimization is used to optimize the structural design of the connecting rod sleeve,and the structural performance parameters before and after optimization are analyzed and compared.It can be seen from the comparison results that the maximum deformation of the structure is reduced from 0.03683 mm to 0.0189 mm,and the stiffness is enhanced.The fatigue life of the connecting rod sleeve is improved after optimization,from 1.451E+005 before opt imization to 1.0E+006.The strain of the connecting rod device optimized by the connecting rod sleeve is reduced by 41.4%;the strength,rigidity and fatigue life of the optimized connecting rod device are improved to achieve the optimization purpose.Then,Six Sigma Analysis(Six Sigma)technology is used to analyze the safety factor probability distribution of the optimized connecting rod sleeve structure,and the reliability of the optimized structure is analyzed to provide a practical reference for the design of the connecting rod sleeve. |
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