Abstract: Aiming at the problem of sealing failure of pipeline gate valves due to the wear of the contact surfaces of the sealing structure, taking the code Z943Y300Lb highpressure pipeline flat gate valve as an example, the wear characteristics of its floating seal structure were executed by means of theoretical derivation, simulation and experiment analysis. Firstly, by using the arbitrary LagrangianEuler (ALE) method and Archard wear model, the thickness of contact surface wear after opening and closing of the floating seal structure was executed by means of theoretical derivation. Then, according to the characteristics of the floating seal structure, a global wear root mean square value was proposed as an evaluation index. Based on the ABAQUS software, the friction dynamics simulation analysis of the floating seal structure was carried out, and the effect of different opening and closing speeds and seal face widths on the wear characteristics was explored. Finally, the predictive model for the amount of seal surface wear of highpressure pipeline flat gate valve was established, the allowable wear life at the equal thickness of wear was predicted, and the simulation results were verified with the least squares method. The results indicate that comparing with the other areas, area Ⅰ and area Ⅱ have a higher amount of wear. The opening speed has a large influence on the wear life of the seal structure of flat gate valve. As the opening speed increases, the interval wear life of the seal structure tends to first increase and then decrease. When the opening speed is 210 mm/s, the seal structure has the maximum wear life. Within a certain range, wear life increases as the width of the sealing surface increases. The research and analysis can provide a theoretical basis for the optimal design and life prediction of the seal structure of flat gate valve.
Key words: high-pressure pipeline flat gate valve; Archard theoretical model; arbitrary Lagrangian-Euler (ALE) method; root mean square (RMS) value; failure of floating seal structure; opening speed;wear life