Finite element simulation analysis of the working process of a ship's gun firing pin

The firing pin is a key part of the artillery, firearms and other weapons systems to fire, a ship gun firing pin in the firing process of the fracture failure phenomenon. Inspection and analysis of the fracture of the firing pin, found that there are two fatigue crack sources on the fracture surface of the firing pin, so that the firing pin in the work of the stress concentration phenomenon, in the process of repeated firing, the location of the stress concentration of fatigue cracks lead to fatigue fracture of the firing pin. For the firing pin fracture problem, this paper uses ABAQUS software to establish a firing pin working process finite element model containing 28 parts such as the gun tail, body tube, switch latch mechanism, firing mechanism, etc. Through simulation, it is found that the stress concentration of the firing pin occurs at the moment when the cocking cam retracts the firing pin, due to the fact that the cocking cam retracts the firing pin project will produce multiple impacts with the firing pin and the radial vibration generated by each impact is the opposite direction of vibration, resulting in a radial impact when retracted, causing the stress concentration at the location of the neck of the firing pin. The direction of vibration is opposite to the last impact, resulting in the firing pin in the retrieval of the radial impact, so that the firing pin neck position stress concentration. By comparing and analyzing with the actual fractured firing pin, it is found that the location of stress concentration when the firing pin is retracted is consistent with the location of the fatigue crack source, which verifies the correctness of the simulation and provides guidance for the optimization design of the subsequent firing pin.