Stress And Strain Monitoring Analysis Of Key Components Of Hydraulic Support

Hydraulic support is an important part of fully mechanized coal mining face.Its working environment is complex and bad,and the load changes greatly.It is very easy to be damaged in the process of use,endangering the safety of equipment and workers.Unmanned and intelligent fully mechanized mining face is the development direction in the future.One of the important contents of its intelligence is to require it to have the function of stress monitoring.At present,the stress analysis of hydraulic support in China is based on the structural safety analysis under single working condition.For the internal loading mode only used in the stress test of hydraulic support,this study is based on the analysis and test of support stress under all working conditions,in order to find out all weak positions of hydraulic support under all working conditions;Measure the weak points of the support through internal and external loading,and compare and analyze the load change law of each component of the support under internal and external loading;Finally,the working conditions of the support top beam are identified by measuring point pressure,column pressure and pin shaft stress.Firstly,taking ZY1000/08/15 hydraulic support as the research object,the stress model of hydraulic support is established.The strength of eight combined loading conditions is analyzed by finite element analysis software,and the large stress points of each component of the support are obtained.A prediction method of weak position of hydraulic support based on modified Goodman curve is proposed to predict the weak position of each component of the support under different working conditions.Secondly,in order to solve the problem that internal loading can not accurately reflect the real stress of the hydraulic support,internal and external loading are used to measure the weak position of the hydraulic support under different working conditions,and the credibility of the test results is verified by the finite element calculation results.The stress variation law of each measuring point of the support under the two working conditions of internal and external loading is compared and analyzed.The stress value measured by the external loading of the top beam and base is less than that of the internal loading,while the stress value measured by the shield beam and the front and rear connecting rods is greater than that of the internal loading.The stress of the pin shaft is calculated,and the variation law of the resultant force of the pin shaft with height under internal and external loading is obtained.Finally,a working condition identification model of hydraulic support top beam based on support vector machine SVM is proposed.Through the monitoring and analysis of the pressure at the measuring point at the weak position of hydraulic support,the pressure on the pin shaft and the force on the column,the typical sudden change working conditions of hydraulic support are identified.Through the combination of the above theory,simulation and test,the weak points of each component of the hydraulic support are studied,and the working condition of the top beam is identified by monitoring the weak position of the support.This study provides a certain basis and reference for the development of underground intelligent support and the health maintenance of support.