Research On The Measurement And Analysis Method Of Roadheader Load Spectrum Based On Data Recorder

With the continuous improvement of the degree of mechanization of coal mining,the higher requirements have been put forward in the speed of working face.High efficiency mechanized tunneling is necessary to realize high production and high efficiency in the mine,and it is also the development direction of the roadway excavation technology.The load spectrum is an important basis for the structural design and improvement of the boring machine.It is an important task to ensure the safe and efficient production of coal mine in the process of coal tunneling,which is a fast,accurate and effective way to measure the load of roadheader under actual working conditions.However,due to the harsh nature and complexity of the underground environment,it is difficult to measure the load spectrum based on the actual working conditions of the underground mine,and there are few reports on domestic and foreign research.The results show that the load spectrum can be used in the fatigue test or structural design after the actual load has been compiled.It is divided into two categories,continuous spectrum and discrete spectrum.Discrete spectrum by all levels of the load and frequency according to some sort of method,the continuous spectrum by the load process directly.If used for fatigue experiments,continuous spectrum can more truly reproduce the load history,but the experimental requirements are high and expensive,and discrete spectrum due to the load is divided into different grades,which can effectively reduce costs.The load spectrum representation is generally divided into two kinds: in the amplitude domain frequency domain to be described.In the mechanical test,the load amplitude distribution characteristics is commonly used.Generally the first load signal discretization,make it into a load data sequence,and then find the amplitude of the load changes in size and count processing.Therefore,the measurement and analysis technology of downhole measured load signal has always been the subject and research direction of many scholars.At present,there are three kinds of load spectrum compiling theory: cycle counting method,load-time process reengineering and fatigue damage theory widely used in various fields.However,due to the specific work environment of the coal roadway and the special requirements of load testing system and instrumentation equipment,the measurement and compilation of load bring many technical bottlenecks,interference factors,data acquisition and data interpretation difficulty and so on.This also makes the existing load spectrum preparation method has a certain flaw.After analyzing and comprehending the principle of measuring and compiling many load spectra,a method of measuring and analyzing load spectrum of roadheader based on large capacity data recorder is proposed.In this method,the EBZ160 roadheader produced by Shijiazhuang Coal Mine Machinery Factory was used as the experimental prototype and a whole set of sensor detection system was installed.Based on the collected data in the coal mine,the load of key components of the roadheader was analyzed and studied.In this paper,the operation and state information of the roadheader read and stored by the data logger are studied,and the load of the roadheader is analyzed in detail.According to the load of the cutting head,the loading model is established,and the three-way data are obtained from the data.Force and resistance moments,the load-time history under single cycle is analyzed.According to the pressure measured by the pressure transmitter,by analyzing the control circuit and the cylinder structure,the load-time course of the rotary cylinder and the lift cylinder under single cycle is studied,and the time-domain and amplitude-domain eigenvalues are calculated.The load spectrum is compiled and expanded into the working load spectrum,and the method of measuring and compiling the measured load signal is put forward.The main research results and conclusions are as follows:(1)The load test method of roadheader is studied and the test system is constructedThe underground model EBZ-160 second-generation roadheader is measured.Service location is the Jidong Xingdong mine 1100 south mining area and 1100 centralized mining transport roadway in southern mining area.The tunnel section is trapezoidal.Based on the self-developed "data logger",various status information and control information of roadheader are determined and set up.Such as phase current of hydraulic motor,hydraulic pressure of hydraulic oil and swing of cutting arm etc.This information sent by the PLC or feedback from the sensor to the PLC register,and then transmitted through the RS232 serial communication to the large-capacity solid-state hard drive.Through the establishment of roadheader operating information database,the working condition of roadheader is analyzed,and the load spectrum is measured and analyzed.It provides the necessary data for the optimization of cantilever roadheader.The test system uses the BYD-60 mine explosion-proof pressure transmitter to measure the oil pressure signal.It uses the data recorder to collect YBUD-200 / 110-4 / 8(1140)flameproof two-speed three-phase asynchronous Cutting motor current value,working voltage,estimating cutting motor power and torque value;selecting W18 LD dual velocity sensor to measure horizontal angle of cutting arm,selecting GUC360 mine inclination sensor to measure cutting arm vertical angle.In the work,the whole vibration is strong,especially the cutting part and the rotary table part,using intrinsically safe vibration acceleration sensor to record the vibration signal.The use of roadheader control box record the measured state signal and control signals,with the PLC recording the work of roadheaders control signals and switch signals,such signals can be used to help determine the roadheader cutting conditions and boring machine Pose and other information.(2)Rain flow count method of preparation of driving oil cylinder load spectrumWhen the cutting head of the roadheader is cut horizontally,it is finished by a pair of synchronous lifting cylinders.when the cutting head vertically cuts the coal wall,it is finished by a pair of rotary hydraulic cylinders.So the lift,rotary cylinder pressure is real-time changes in the urgent need to carry out the study of the hydraulic cylinder aspects of the load.First calculate the position of the cutting arm,then realize the data conversion of the pressure signal of the rotary cylinder and the lifting cylinder.According to the structure dimension and the connection way of the cylinder,the load calculation formula is obtained.Four criteria for the judgment of the cutting cycle and the data selection are proposed.The data are selected and processed by the four criteria,and the statistics and simple analysis are carried out in the time domain and the amplitude domain,and the rain flow counting method is adopted.Load spectrum,and extended to the working load spectrum,the data on the boring machine cylinder and improve the dynamic performance and reliability of the work of great help.(3)Rain flow count method of preparation of heading machine cutting head load spectrumThe cutting head is the direct loading part of the boring machine,and the cutting motor is the direct power source to drive the cutting head.For many years,many researchers have carried out structural analysis,simulation and optimization design on the cutting head,but can not get the real load data of the cutting head.In this paper,the two parameters of power and torque of the motor are firstly analyzed in the "data recorder",from the time domain analysis and the probability density.Then the mechanical model of the cutting head is established.The load history is deduced from the measured data of the instrument,and the load spectrum is obtained by counting the load signal and expanding the cumulative frequency map.These provide the basis for the practical work analysis and the analysis and improvement of the cutting head in the tunneling machine.Cutting head is directly affected by load part of the roadheader,cutting machine is a direct power supply to drive the cutting head.Over the years many researchers on the cutting head structure analysis,simulation and optimization design,but can't get the real load data at work.This article first through the "data recorder" in two of the cutting motor power and torque load related parameters,from two aspects of time domain analysis,probability density analysis;Then cutting head by residual learning model,combining with the downhole data recorder measured data to deduce the loading process,by counting the load signal processing and cumulative frequency diagram extension of load spectrum,the work for boring machine cutting roadheader underground actual situation analysis and provide a basis for the analysis of the cutting head to improve.(4)Different cutting conditions affect roadheadermachine load machineBoring machine working environment is complex,cutting coal,rock,boring machine when the load changes significantly,the body vibration also changes dramatically.The same cutting head speed and cutting arm swing speed change the boring machine cutting.So the study of load variation under different cutting conditions is an important aspect of studying the load of roadheader.The main contents are as follows: The research on the change of cutting speed of different hardness coal and cutting head,The influence on the load when the roadheader is cut when the speed changes.When the roadheader is working,the cutting arm needs to change the position in space to complete the cutting task.When the same cutting action is done in different positions,the power of the cutting motor and the pressure of the rotating hydraulic cylinder are different.And the load parameter of the maximum pose of the roadheader is determined as the basis for the design and improvement of the roadheader.(5)Study of stress strain and fatigue strength machine rotating tableRotary table is an important part of the machine,it connects frame,support,cutting arm implementation of drilling cutting,cutting head sweeps the coal and rock,elevator,rotary cutting arm movement,and the complex impact load from the cutting head.The essences of these loads are in rotary table institutions,and pass through it to the rack.Therefore,rotary table design is reasonable directly influences the working performance and reliability of the roadheader,so the stress strain of the rotary table,modal,fatigue strength is analyzed.According to the principle of cutting force synthesis department,will be cut in the coal rock tunnel operation state of each resolution to lift extrusion,rotary extrusion and the analysis of cutting head rotation cutting force synthesis.The cutting department was established based on ADAMS virtual prototype technology and virtual prototype dynamics simulation model of rotary table,select cutting head in the next section,the middle and the upper section of left right side of the research of force bearing analysis on the three groups each position of static finite element analysis,and rotary table to obtain the corresponding stress nephogram.Rotary table of the free state of modal analysis,determine the revolving stage 6 order modal vibration mode.Because EBZ160 roadheadermachine rotary table for large low alloy steel castings,its material is ZG35 CrMo,establish a rotary table SN curve,and fatigue analysis using the AWE to rotary table.