35 Mm Anti-aircraft Bombing Bore Cause Analysis

Bore premature is a type of very dangerous phenomena in the use of guns, it not only destroys the weaponary but also injures the men who use them, so it has been regarding terribly. Finding out the reasons of the bore premature is a very important work to avoid the havoc.In order to analyze the reasons of the bore premature arose in the 35 mm antiaircraft gun, MATLAB language is compiled to solve the mathematic model that describe the 35 mm antiaircraft projectile's motion in the bore based on gun interior ballistics. The physical model is set up using a finite element method and the launching strength of the 35mm antiaircraft projectile is calculated in the different instances with the ANSYS software.The strength of projectile body and the strength of the fuze body are enoughin the projectile and fuze whose connection thread is M26, when the ballistic environments are normal. And when the band material of the 35 mm antiaircraft projectile is misapplied S10A from the pure iron, the strength of projectile body is still enough, but the stress in the fuze body is beyondσ_b, the fuze is likely to be broken, then the high-pressure and high-temperature gas from the propellant may get to the high explosive chamber through the fuze body, and bore premature will happen immediately. The desensitized propellant's invalidation will result in bore premature in the same way.When the thread that connect the projectile body and the fuze is M25 instead of the M26, the weakness areas is thickened in bottom of the fuze body, so the misuse of the band materials has no menace to the projectile and fuze system, the launching strength of the projectile and fuze system is satisfied. And the complete invalidation of the coating layer of desensitized propellant cannot lead bore premature in this case.The weakness area of the fuze body is also strengthened when the projectile and fuze system is ameliorated, so the launch safety of the fuze is increased.When the band material is not misused and the content of the desensitizer is stable, the strength of the projectile and fuze system whose connection thread is either M26 or M25 is enough, it shows that the projectile and fuze system's strength satisfied the launch safety.