Investigating the effect of the gap between the throttling ring and the control rod in the hydraulic braking mechanism on the stability of the cannon during firing

In this paper, a mathematical model is developed to describe the dynamics of the recoiling part of the cannon during both the recoil and counter-recoil (push-up) phases. Based on the analysis of the forces acting on the cannon during these phases, expressions are derived to evaluate the stability conditions - specifically, preventing the cannon from overturning upward during recoil and downward during counter-recoil. The influence of the gap between the throttling ring and the control rod of the recoil braking mechanism on the stability of the 85mm D44 cannon is investigated. The results show that a change in the gap to 1 mm does not cause instability (either upward or downward overturning) but does significantly affect the recoil velocity, recoil distance, and final impact speed during the counter-recoil process. These changes can potentially reduce the durability of the components or even cause structural failure of the cannon mechanisms. Therefore, it is essential to consider the tolerances of these parts during technical inspections, maintenance, and repair. This research can contribute to improving the reliability and maintenance effectiveness of field artillery systems under actual combat conditions.