Research On Electro-hydraulic Integrated Testing System For Multi-way Valve Of Hydraulic Excavator

With the rapid development of engineering machinery, the sales of excavator aregrowing up day by day. Multi-way valve as one of the important elements of excavatorhydraulic system, its performance directly determines the quality and technical level ofexcavator. As the loader hydraulic system fault is very difficult to be detected, thecomprehensive and accurate performance test of the multi-way valve is important inthe front of the assembly of the machine. But The function of the existing testingsystems for multi-way valves are not very versatial，and their process is complexed tohandle and the efficiency is very low. In this thesis, a set of efficient and convenientoperation integrated test system for multi-way valve of hydraulic excavator will bedesigned by using electro-hydraulic proportional control technology based on therelated standards of multi-way valve technology and related technical requirements,and combined with the common features of the modern excavator multi-way valve. Asthe testing system is hard to detect the displacement of the spool valve and it will giveeffect to the measurement, according to the test results the research of displacementcompensationon of the spool will be given. The main contents of this dissertation areas follows:1、The principle and characteristics of the multi-way valves are Introduced and thedevelopment trend also summarized; Then carries on the analysis of the presentresearch situation of testing multi valves, and present the significance and the mainresearch content of this paper.2、The overall scheme of the electro-hydraulic controlled comprehensive testsystem of the excavator multi-way valves is design, based on the multi-way valverelated testing standards and related technical requirements, and combined with thecharacteristics and functions of researched and developmented excavator multi-wayvalve. Determine the functional unit scheme through analysis and comparison.3、Each function module of the hydraulic system is designed based on theprinciple of compact design and convenient operation, and make the calculation andselection of the related hydraulic components. then complete the software andhardware design of the computer control system to achieve a high degree ofautomation control of the testing system, automatic data acquisition, processing andreal-time display.4、Based on the designed comprehensive testing platform, does some research on the test to the excavator multi-way valve. The method of implementation of therelevant test project is introduced in this paper. Combining the function principle andstructure characteristics of the multi-way valve, carries on the analysis to the testresults, verify the accuracy and ease of operation of the testing system.5、On the basis of experiments, the data error between experimental data andtheoretical calculations is analysed, the sources of error are analysed and researched.Establish the displacement compensation algorithm of the main valve spool tocompensate the numerical of test results. In order to achieve the correct calculation oftheory and experiment, reduce the experimental error function.