Self compensation design of main seal structure of high temperature and high pressure ball valve
                                                                      LIU Xian dong, GU Ji nan
                             （College of Mechanical Engineering, Jiangsu University, Zhenjiang 212000, China）

Abstract: In order to solve the ball valve in the harsh conditions encountered in the main sealing structure, the sealing surface of the friction and wear, resulting in leakage of the valve, sealing performance and other issues, based on the sealing principle of ball valve, the advantages and disadvantages of the existing sealing structure were studied, CAD and finite element analysis technique were applied to the design of the ball valve, requirements for sealing specific pressure based on sealing performance, the relation between sealing surface width and seal specific pressure was analyzed, a method was presented that used the pressure of fluid medium to provide axial thrust of valve seat and force the valve seat to compensate for the loss of friction, so as to achieve self compensation sealing effect, the model of self compensation main seal structure was designed by using modeling software SolidWorks, and the finite element simulation analysis was carried out by using the grid partition plug in. The results show that in the friction wear, the design can through the self compensation function to increase the width of the sealing surface and sealing structure, there by reducing the sealing surface than the pressure seal, the valve sealing performance is improved.

Key words: main seal; sealing surface width; self compensation; structural design