The Life And Reliability Analysis Of The Locking Mechanism Of Firearms Considering Multiple Failure Mechanisms

This study uses an automatic rifle locking mechanism as the research object.Combined with the actual use of the locking mechanism.Then analyze the locking mechanism under consideration of the failure mechanism of the deformation and the impact fatigue failure mechanism.Finally,the question of the life and reliability of the locking mechanism is studied under the comprehensive consideration of multiple failure mechanisms.The main work of this article is as follows:(1)In view of the failure caused by the shell deformation,the axial force of the shell is analyzed in the firing process.Calculate the axial deformation of the shell after firing.And the theoretical formula for calculating the limit elongation of the cartridge case is derived,which is prepared for the failure analysis of the subsequent locking mechanism.(2)For the failure caused by the deformation of the shell,the composition of the locking gap is analyzed.Then a finite element analysis model for the elastic deformation of the locking mechanism is established.The components of the locking gap is studied and calculated.The failure caused by the deformation of the locking mechanism is judged by whether or not the cartridge shell traverses.By comparing the relationship between the locking gap and the shell’s ultimate elongation,we can determine whether the cartridge case will break.The failure mechanism of locking mechanism under deformation is further revealed.(3)For the failure problem of the locking mechanism under the impact load,a finite element analysis model is established for the locking mechanism.And through the finite element analysis results and the fourth strength theory,it is concluded that the maximum stress value of each component of the locking mechanism do not exceed the yield limit of each component material.The rain data counting method is used to process the data.The stress and strain curve equation and modified Nobel method are used to calculate the local stress and strain.Then,the fatigue life of the firearm locking mechanism is analyzed based on the fatigue damage law and Miner linear fatigue cumulative damage theory.(4)The strength reliability of the locking mechanism of the locking mechanism under the impact load is analyzed.And the randomness of the pressure and material parameters is taken into account.Based on the impact fatigue analysis model above,the fatigue strength reliability of the heavy load is analyzed using ABAQUS and SPSS software.(5)Considering the multiple failure mechanism comprehensively,the service life of the locking mechanism is analyzed and calculated.In the finite element analysis model,the locked gap is added to the study.At the same time,the Matlab life analysis program of locking mechanism based on multiple failure mechanism is compiled.In consideration of the limit of the locking clearance,the overall life of the locking mechanism is analyzed.