Frame Structure Design Of Caving Shield Hydraulic Support With Double Pillar

Before the comprehensive popularization of new energy,fossil energy is still the main energy.Because the energy structure of our country is more coal,less oil and less gas,so coal is still the main body of fossil energy in our country at this stage.In modern coal mining technology,comprehensive mechanized mining is the most advanced mining method at present.As the main component of the comprehensive mechanized coal face,hydraulic support can effectively isolate the mined out area of the face and effectively control the unstable mine stress.However,the existing hydraulic supports have some problems in the field use,such as the uneven loading of the four column type,the poor stability of the support type and the high cost of the support shield type.This paper aims at the design task of a kind of hydraulic support,in order to design a hydraulic support system that can meet the field use.The method of comparative analysis is used to determine the scheme,the traditional method is used to design the mechanism,and Simulink is used to verify the kinematic accuracy of the mechanism.The internal force law of the connecting rod under different attitude is analyzed by programming in MATLAB,and solid modeling and strength analysis are completed in Solidworks.Through consulting a large number of documents,the scheme design of the hydraulic support is completed by comparative analysis.In terms of the selection of the height of the support coal outlet,the lower coal caving technology with larger development space is selected;in terms of the structure of the hydraulic support,the shield type hydraulic support is finally determined;in terms of the form of the four-bar mechanism,the positive four-bar mechanism with higher space utilization is selected;in terms of the number of hydraulic pillars,the two-bar mechanism with better balance is determined as the optimal choice.Finally,it is determined that the type to be developed this time is the shield type low caving coal hydraulic support with two positive four-bar linkage mechanism.After the scheme of the hydraulic support is determined,the corresponding mechanism design is carried out.In the process of mechanism design,firstly,the traditional analytical method and graphic method are used to quickly determine the mechanism parameters,and then the Simulink numerical simulation is used to verify the kinematic accuracy of the mechanism top beam under the parameters.Finally,the relevant laws between the parameters and the track accuracy are studied,and the mechanism parameters are corrected again,and finally meet the engineering design requirements.In the relationship between the parameters of each component and the motion accuracy of the top beam of the support,it finds out that the initial design is not up to standard,which is also the main breakthrough direction of parameter correction.In the design process,many parameters are not determined by mechanism parameters,but depend on factors such as scraper parameters,shearer parameters and mine pressure.For this kind of parameters,the empirical design method is used.These parameters mainly include the length and width of the top beam,support spacing and support height.In the first step,according to the multi link mechanism of the hydraulic support,a simple box girder model is established,and the overall press frame simulation is done to confirm the rationality of the layout of the main reinforcement plate.Referring to the structural design of the main components of a four column hydraulic support,the model is refined on the basis of the original simple box beam,and the detailed modeling of the top beam,shield beam and base is completed.Finally,the virtual assembly of the roof beam and the shield beam is carried out,and the interference check is carried out to ensure that there is no interference between the roof beam and the shield beam when they move.To ensure safety is the first priority in engineering design,so whether the hydraulic support can achieve the expected performance needs to be tested.According to the characteristics of the hydraulic support mainly bearing the distributed static load,the distributed load acting on the top beam can be simplified as a concentrated load at a specific location,which is equivalent to the total pressure acting on the top beam.In the process of strength check,the influence of different support height and equivalent concentrated load position on the internal stress of hydraulic support is systematically simulated and analyzed,9 working conditions is used to finish this step in MATLAB.Finally,the strength of the main box girder components of the hydraulic support is checked by using the simulation module of Solidworks,and the weak links of large deformation and high stress-strain under some working conditions are partially strengthened.Finally,the structural design that the strength can meet the requirements under each working condition is achieved,which ensures that the hydraulic support designed this time can meet the performance requirements.