Combined Simulation Of Positive Flow Excavator And Pressure Loss Analysis Of Hydraulic System

As a common construction machinery,excavator plays an irreplaceable role in many fields.The hydraulic system of excavator is one of the most important and complex systems of excavator.According to the development history and current situation of energy-saving technology of hydraulic excavators at home and abroad,based on the analysis and research of energy-saving technology of excavators,the pressure loss of hydraulic system of excavators is theoretically analyzed,and the electro-hydraulic combined simulation model of excavators is established.The pressure loss of hydraulic system of excavators under typical working conditions is mainly analyzed,and the pressure loss of whole excavators with different actions is explored.The loss of specific values and pressure loss distribution were measured and analyzed.Combining with the structure of excavator pipeline and the layout of multiway valves runner,the way of multi-way valve confluence and pipeline are improved to reduce the pressure loss of hydraulic system.By reducing pressure loss,the energy-saving efficiency of hydraulic system can be improved and the driving force of excavator can be improved which is verified by simulation.In this paper,the hydraulic system of the large hydraulic positive flow excavator of SANY is taken as the research object,aiming at reducing the pressure loss of the excavator.The main contents of this paper are as follows:Firstly,the significance of energy saving of hydraulic excavators is summarized,and the characteristics of various hydraulic transmission systems of excavators at home and abroad are analyzed and compared.On the basis of summing up the work of predecessors and combining with the existing conditions,a set of methods for improving the confluence mode of multiway valves and pipe parameters of existing excavators are put forward which are easy to reduce the pressure loss.Then,the structure and principle of the main components of the hydraulic system of positive flow excavator are analyzed,and the mathematical models of the displacement regulating mechanism and multiway valve of the main pump are established.The hydraulic system simulation model of excavator is established by AMESim,the mechanical structure model of excavator is established by ADAMS software,the electronic control system model is established by AMESim,and the joint simulation is carried out by ADAMS and AMESim.The dynamic response of hydraulic system and mechanical structure under typical working conditions is compared with the experimental data which verifies the accuracy of the model.Finally,the joint simulation model is used to solve the hydraulic pressure loss under typical action,and the distribution of pressure loss in hydraulic system is analyzed when the arm in with the greatest pressure loss.In order to reduce the pressure loss and improve the energy utilization ratio of excavator,the combination of the arm valve 1 and 2 in the multiway valve was replaced by the combination in the external pipeline of the multi-way valve,and the inner diameter parameters of the pipeline were increased appropriately.On the experimental platform of excavator positive flow hydraulic system,the dynamic and static response characteristics of excavator positive flow pump and multiway valves are tested,which further verifies the accuracy of the simulation model.At the same time,the whole excavator is experimentally analyzed.The experimental results verify the correctness of the combined simulation model of excavator.