Performance of the Internal Mixer’s end Face Mechanical Seal with Isosceles Right Triangle Textures

Abstract

To improve the sealing performance and prolong the service life of the internal mixer’s end face mechanical seal, the surface texture technology was introduced to the end face mechanical seal in this paper. Different arrangements of isosceles right triangle textures were designed on the rotating sealing ring to study the effects of texture parameters and working parameters on the performance of the textured mechanical seal. The results indicate that under steady-state conditions, different arrangements of isosceles right triangle textures produce obvious hydrodynamic pressure effects and cause the mechanical seal to produce oil film capacity. Meanwhile, the Rt2 arrangement mechanical seal can obtain the lowest end leakage. What’s more, Rt1, Rt2, Rt3, and Rt4 arrangements show better sealing performance when their texture area ratio Sp = 21%, 39%, 21%, 30%, respectively, so do the four arrangements when their texture depths hp = 2∼4 μm. Appropriately reducing the rotor speed n and increasing lubricant viscosity η is helpful to improve the work performance of the textured mechanical seal. Under unsteady-state conditions, the maximum oil film pressure, leakage, friction coefficient and sealing gap of the textured mechanical seal change periodically with the load. When hp = 3 μm, the Rt2 arrangement has lower leakage and friction coefficient. Further, lower speed and lubricant viscosity are beneficial to reducing the leakage and friction of the textured mechanical seal of the internal mixer.