Design and Transient Flow Characteristics of New Differential Large Flow Safety Valve

This paper presents a novel differential-type high-flow safety valve, with a rated flow and pressure of 3000 L/min and 50 MPa respectively, aimed at enhancing the impact resistance and stability of hydraulic supports. Based on the Ansys Fluent platform, dynamic mesh technology and User-Defined Functions (UDF) were employed to identify the optimal damping hole radius for the differential high-flow safety valve. The transient fluid characteristics throughout the opening process until stable unloading were simulated for valves featuring damping hole radii of 1 mm, 2 mm, and 3 mm. Based on the optimal damping hole radius, test samples were developed high flow safety valves and constructed a rapid dynamic loading shock test rig to evaluate their shock resistance characteristics. Results indicate that a damping hole radius of 2 mm achieves the best overall performance in both transient response characteristics and operational stability. The differential high-flow safety valve demonstrates rated flow and pressure of approximately 2996 L/min and 49.4 MPa respectively, with valve core opening time of under 2 ms, unloading time of under 5 ms, and pressure overshoot of below 20%. These findings validate the structural rationality of the differential high-flow safety valve and confirm its advantages in rapid unloading speed and excellent impact resistance.