Optimization Design And Structure Strength Analysis Of Working Equipment Of 8m~3 Mining Excavator

Mechanical mining excavator is mainly used in open air minning industry and earthworkengineering,espacially widely used in open coal mine,iron ore and building materials.Not only can it save labor force,but also the machine can improve work efficiency greatly.Accompanied with the rapid development of industrial technology,people's demend for energy is on the increase,espacially the requirement of coal and steel rises rapidly,therefore,the requirement of mining excavators are also getting higher and higher.In the actual working process,excavator working device is the main part when the machine is under operation,the arm and bucket suffer more force and deformation which will result in fracture,thus,it is very important to design parameters in the design of the excavators,whether it has a reasonable design have direct effect on the performance of excavators.In the course of designing single bucket excavator,initial parameters such as bucket volume,outline-size,working-size have been decided,the machine which has flexible link with grab-bucket and lug-shovel can make sure of the size of working device,but in terms of bucket having rigid relation with excavators,the working device under the same working size will get different structure project,thusin order to gain better structure program,it needs to analyze and compare different working devices so as to obtain a favorable design of frame.As a part of analysis of issues of the 8 cubic meter-mining excavator,in this paper,Genetic Algorithm Tool of MATLAB will be used to optimize parameters of working device for the purpose of offering theoretical basis which can improve the working device,at the same time,using ANSYS analysis software to analyze statics of the working device and put forward reasonable and improved structure program,such method gets rid of traditionaldesign ideas,avoids upbuilding physical prototype,saves pilot funding and shortensthe product development cycle,in summary,all what will have been done will make good sense to optimize and improve the working device,will get very important practical significance. The machine weight will be regard as the main parameter when optimizing design It also needs to carry out force analysis and motion analysis of single bucket of the mechanical shovel excavator in order to set up mathematical model of optimal design.then Genetic Algorithm Tool of MATLAB will be used to put up reasonable optimization,and then in contrast to the objective function curves of the optimal program under different working condition,the ratio of push to lift-velocity on the points of the bucket'strajectory is also compared,comprehensive analysis will be used to get frameand performance under different conditions after optimal design.at last,ANSYS software will be used to analyse statics of the working device so as to compare having been optimized mechamical aspects of the performance with that having not been done.moreever,putting forward reasonable and improved project,finally,optimizationand progressness of structure should be proved effective.1.On the base of checking a large number of literature,it has been analysed the mechanical excavator'sworking device and static suffered,and get a reasonable of strajectory of the bucket.then it can infer a angle between wire rope and center line of bucket-stick as well as the ratio of push to lift-velocity.meanwhile,it also needs to analyse mining resistance and lifting force so as to offer theoretical basis for the mathematical model and optimal design.2.By analysing the structure and force of working device,we can get the main factors which have effect on the performance of the excavators,on the base of analysing,it can build sound mathematical model,choose lifting force as research focus and select the angle between wire rope and center line of bucket-stick as well as geometry as the objective function.According to experience from the designer,motion performance,the geometry and structure'size,the working size and boundary conditions,a reasonable constraint can be set up.3.Under the consrtaint,we can use Genetic Algorithm Tool of MATLAB to optimize mathematical models which have been put up.in this paper,optimization problem belongs to goal of non-linear programing,the usual solving method is to handle objective function properly when solving the multi-objective optimization problem, changing the multi-objective optimization problem into single-objective optimization problem.this thesis will re-structure multi-objective optimization problem into a evaluation function,so it can change the multi-objective optimization problem into single-objective optimization Problem.because of the nonlinear of objective function and constraint,the study is complicated,but we can use Genetic algorithm Tool of MATLAB to obtain reasonable analysis,when the bucket-stick comer from 0 degree to 90 degree,different optimal results can be received.then choose four special condition,make confrontation among lifting force,a angle between wire rope and center line of bucket-stick,geometry size and the ratio of push to lifting-velocity,finally,we get optimal results.4.According to the basic size of different parameters on the working device,it may build finite model.Under operation,the force which booms and bucket-stick undertake is being analyzed,we select the worst conditions of the boom and bucket,when bucket fully extends,it has a direction perpendicular to the center line of boom,at this point, booms shoulder the biggest force;the bucket is in the horizontal position and extends normally,excavatoring is in high-finale pushing position,the bucket encounters obstacles(rocks),the foece(Q) of the lifting pulley type reaches a maximum,a bending moment the bucket suffered is close to a maximum.In the above-mentioned condition ,before and after optimization of moving arm and bucket is under ANSYS finite element analysis of statiac respectively.comapring pre-optimization of the force the moving arm and bucket suffered with optimized force suffered,we may find out the location of the maximum on the boom and bucket,and bring forward a rational and improved program to verify optimization and rationality of the working device from mechanical strength.The thought of optimal design and frame improving may be applied to other similar excavators in design and development as well as offered theoretical basis for optimization design and improving structure of other parts of excavators.