Sealing device for gas-liquid two-phase fluid medium under variable working conditions

A sealing device for a gas-liquid two-phase fluid medium under variable working conditions, comprising a rotating shaft and a housing;

• wherein a chamber formed by the housing is configured to accommodate the gas-liquid two-phase fluid medium;
• the sealing device further comprises a labyrinth sealing mechanism and a fluid dynamic-pressure mechanical sealing mechanism, wherein
• the labyrinth sealing mechanism and the fluid dynamic-pressure mechanical sealing mechanism have a mutually synergetic effect;
• sealing buffer chambers are arranged between the labyrinth sealing mechanism and the fluid dynamic-pressure mechanical sealing mechanism with double end faces;
• the fluid dynamic-pressure mechanical sealing mechanism comprises stationary rings and movable rings, wherein:
• each of the stationary rings oppositely abut against one of the movable rings;
• the stationary rings are respectively fixed on stationary ring covers formed by the housing through metal sealing rings, respectively;
• the movable rings are fixed on the rotating shaft through sealing rings, respectively;
• a spring is fixedly connected to pushing rings, and each of the pushing rings oppositely abut against one of the movable rings;
• sealing packings are arranged in chambers between the pushing rings, the movable rings and the rotating shaft;
• a limiting sleeve is arranged on an outer circumference of the fluid dynamic-pressure mechanical sealing mechanism;
• and
• an isolation sleeve is arranged between the spring and the rotating shaft;
• the labyrinth sealing mechanism comprises a plurality of sealing teeth arranged axially, wherein the plurality of sealing teeth are ladder-shaped trapezoidal convex teeth, and ladder-shaped trapezoidal grooves formed by the housing cooperate with the plurality of sealing teeth to form a zigzag sealing channel of the labyrinth sealing mechanism;
• a plurality of spiral areas formed by micropore groups are arranged on dynamic-pressure sealing end faces of the stationary rings, each spiral area comprises branch areas adjacent to outer circumferences of the stationary rings and deviated along a rotating direction of the rotating shaft, and the branch areas are formed by the micropore groups;
• pore diameters of the micropore groups in the plurality of spiral areas and pore diameters of the micropore groups in the branch areas gradually decrease in a radial direction, and a cross section of a micropore of the micropore groups is one of a trapezoid and a ladder-shaped trapezoid;
• and
• a part of sealing end faces of the movable rings adjacent to outer circumferences of the movable rings have an inclined angle of 3 to 8 degrees from the radial direction.