Labyrinth seal structure with liquid storage tank for active disc centrifugal separator

Abstract

The utility model discloses a labyrinth seal structure with a liquid storage tank for an active disc centrifugal separator, which is formed by a non-contact combination surface of an impeller and a lower bearing seat in the separator and comprises at least two gaps which are communicated in series to form an oil return passage, and the adjacent gaps are positioned in different planes. And a liquid storage tank is formed in at least one gap. According to the labyrinth sealing structure, on one hand, the flowing resistance of return oil can be increased, the kinetic energy of an oil body can be dissipated, on the other hand, the oil sealing effect is improved through the additionally-arranged one or more liquid storage grooves, the sealing effect of the separator on an oil return path is obviously improved, and therefore the phenomenon that purified gas flows into a driving chamber is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of oil-gas centrifugal separators, in particular to a labyrinth sealing structure with a liquid storage tank of an active disc centrifugal separator. Background Art

[0002] At present, during the compression ignition process of a fuel engine, a small amount of the high-pressure combustible mixed gas and combustion gas in the cylinder will enter the crankcase through the gap between the cylinder and the piston, forming a mixed gas mist containing oil mist, air, water vapor and exhaust gas. These mixed gas mists gather in the crankcase, causing the pressure in the crankcase to be too high, affecting the engine working condition and damaging the crankcase seal. In order to avoid and reduce the impact of the mixed gas in the crankcase on the engine working condition, it is necessary to separate the mixed gas mist from the crankcase into gas and liquid.

[0003] The Chinese patent document with publication number CN109107778A discloses an active disc centrifugal separator, which is composed of a separation chamber housing, a separation rotor (upper bearing and bearing seat, lower bearing and bearing seat, shaft, disc) and a drive chamber (liquid channel, nozzle, impeller) and other parts. During operation, the pressurized liquid sprayed by the nozzle in the drive chamber drives the impeller to rotate, thereby driving the separation rotor to rotate, thereby realizing the separation of oil and gas in the separation chamber, and the separated purified gas is discharged from the gas outlet at the top of the separation chamber, and the separated oil will fall through the liquid outlet on the lower bearing and fall into the oil storage tank on the top surface of the impeller, and under the negative pressure formed by the rotation of the impeller, the oil in the oil storage tank is pumped out and passes through the gap between the lower bearing seat and the impeller to realize oil return. The setting of its oil storage tank can play the role of oil seal to prevent the purified gas from entering the drive chamber. However, during actual operation, it was found that, on the one hand, the oil storage in the oil storage tank was unstable under the negative pressure of the impeller, and on the other hand, the joint surface between the lower bearing seat and the impeller was basically a flat surface with small liquid flow resistance. As a result, the sealing effect was poor only through the oil seal of the oil storage tank, and the purified gas would still leak into the drive chamber. Utility Model Content

[0004] The utility model aims to provide a labyrinth seal structure with a liquid storage tank for an active disc centrifugal separator, which solves the problems of poor sealing effect and easy leakage of purified gas into the driving chamber of the existing active disc centrifugal separator during oil return.

[0005] The utility model achieves the above-mentioned purpose through the following technical solutions:

[0006] A labyrinth seal structure with a liquid storage tank for an active disc centrifuge separator. The labyrinth seal structure is formed by the non-contact joint surface between the impeller and the lower bearing housing in the separator. It includes at least two gaps that communicate with each other to form an oil return passage, and adjacent gaps are located in different planes. At least one gap is provided with a liquid storage tank.

[0007] Further improvement lies in that there are two gaps. One is the bottom gap perpendicular to the impeller axis, and the other is the side gap parallel to the impeller axis.

[0008] Further improvement lies in that there are four gaps. Two of them are bottom gaps perpendicular to the impeller axis, and the other two are side gaps parallel to the impeller axis, and the bottom gaps and the side gaps are alternately connected.

[0009] Further improvement lies in that the liquid storage tank is located at the bottom gap, and the liquid storage tank is opened on the impeller wheel surface.

[0010] Further improvement lies in that there is one or more liquid storage tanks.

[0011] Further improvement lies in that the cross-section of the liquid storage tank is in the shape of V, U, ∪ or inverted trapezoid.

[0012] The beneficial effect of the present utility model is as follows: On the one hand, this labyrinth seal structure can increase the flow resistance of the oil return, dissipate the kinetic energy of the oil body. On the other hand, through the addition of one or more liquid storage tanks, the oil seal effect is enhanced, so that the sealing effect of the separator on the oil return path is significantly improved, thereby avoiding the phenomenon of purified gas leaking into the drive chamber. Description of the Drawings

[0013] Figure 1 It is a schematic diagram of the overall structure of the active disc centrifuge separator;

[0014] Figure 2 It is a schematic diagram of the position of the labyrinth seal structure of the present utility model;

[0015] Figure 3 It is a schematic diagram of various cross-sectional shapes of the liquid storage tank;

[0016] Figure 4 It is a schematic diagram of the structure of Embodiment 1 of the labyrinth seal structure;

[0017] Figure 5 It is a schematic diagram of the structure of Embodiment 2 of the labyrinth seal structure;

[0018] Figure 6 It is a schematic diagram of the structure of Embodiment 3 of the labyrinth seal structure;

[0019] In the figure: 1. Housing; 2. Rotor; 3. Inlet; 4. Outlet; 5. Lower bearing housing; 6. Impeller; 7. Shaft; 8. Labyrinth seal structure; 80. Liquid storage tank; 81. Side clearance; 82. Bottom clearance; 9. Drive chamber. Detailed implementation mode

[0020] The following further describes the present application in detail with reference to the accompanying drawings. It is necessary to point out here that the following specific implementation modes are only used to further illustrate the present application and cannot be understood as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0021] As Figure 1 and Figure 2 shown, the figure shows the overall structure of an active disc centrifuge. The active disc centrifuge includes a stationary separation chamber housing 1. The housing 1 is provided with an inlet 3 for the oil-gas mixture to enter, an outlet 4 for the purified gas to be discharged after separation. A lower bearing housing 5 is arranged inside the housing 1. A shaft 7 is installed through the lower bearing housing 5 and a lower bearing (with a through hole). Rotors 2 for separation are distributed on the shaft 7. The bottom end of the shaft 7 extends into the drive chamber 9 and is provided with an impeller 6. The surface of the impeller 6 will be close to the surface of the lower bearing housing 5. In order for the impeller 6 to rotate stably, the joint surface between the two does not contact. During operation, the rotation of the impeller 6 drives the shaft 7 and the rotor 2 to rotate, realizing oil-gas separation.

[0022] The labyrinth seal structure 8 with a liquid storage tank according to the present invention is formed by the non-contact joint surface between the impeller 6 and the lower bearing housing 5 in the separator. It includes at least two gaps that communicate to form an oil return passage, and adjacent gaps are located in different planes, that is, adjacent gaps can be perpendicular to each other, or arranged at a certain inclination angle, such as an angle of 60°, 120°, 75°, 105°, etc. In addition, a liquid storage tank is provided at at least one gap. There is one or more liquid storage tanks, such as Figure 3 shown, the cross-section of the liquid storage tank is in the shape of a V, U, ∪, or inverted trapezoid, etc.

[0023] The following introduces three common examples of the labyrinth seal structure 8:

[0024] Example 1

[0025] As Figure 4 shown, a labyrinth seal structure with a liquid storage tank of an active disc centrifuge. The labyrinth seal structure 8 is formed by the non-contact joint surface between the impeller 6 and the lower bearing housing 5. It includes two gaps that communicate to form an oil return passage. One of them is a bottom clearance 82 perpendicular to the axis of the impeller 6, and the other is a side clearance 81 parallel to the axis of the impeller 6. And two liquid storage tanks 80 are provided on the surface of the impeller 6 at the bottom clearance 82.

[0026] Example 2

[0027] like Figure 5 As shown, a labyrinth seal structure with a liquid storage tank for an active disc centrifugal separator, the labyrinth seal structure 8 is formed by the non-contact joint surface of the impeller 6 and the lower bearing seat 5, and includes four gaps connected in series to form an oil return passage, two of which are bottom gaps 82 perpendicular to the axis of the impeller 6, and the other two are side gaps 81 parallel to the axis of the impeller 6. The bottom gap 82 and the side gap 81 are alternately connected, and a liquid storage tank 80 is opened on the wheel surface of the impeller 6 at the two bottom gaps 82.

[0028] Example 3

[0029] like Figure 6 As shown, a labyrinth seal structure with a liquid storage tank for an active disc centrifugal separator, the labyrinth seal structure 8 is formed by the non-contact joint surface of the impeller 6 and the lower bearing seat 5, and includes four gaps connected in series to form an oil return passage, two of which are bottom gaps 82 perpendicular to the axis of the impeller 6, and the other two are side gaps 81 parallel to the axis of the impeller 6. The bottom gap 82 and the side gap 81 are alternately connected, and two liquid storage tanks 80 are provided on the wheel surface of the impeller 6 at the two bottom gaps 82.

[0030] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model.

Claims

1. A labyrinth seal structure with a liquid storage tank for an active disc centrifugal separator, characterized in that: The labyrinth seal structure is formed by the non-contact joint surface between the impeller and the lower bearing housing in the separator, and it includes at least two gaps that communicate with each other to form an oil return passage, and adjacent gaps are located in different planes, and a liquid storage tank is provided at at least one gap.

2. The labyrinth seal structure with a liquid storage tank of an active disc centrifugal separator according to claim 1, characterized in that: There are two gaps, one of which is a bottom gap perpendicular to the axis of the impeller, and the other is a side gap parallel to the axis of the impeller.

3. The labyrinth seal structure with a liquid storage tank of an active disc centrifugal separator according to claim 1, characterized in that: There are four gaps, two of which are bottom gaps perpendicular to the axis of the impeller, and the other two are side gaps parallel to the axis of the impeller, and the bottom gaps and the side gaps are alternately connected.

4. The labyrinth seal structure with a liquid storage tank of an active disc centrifugal separator according to claim 2 or 3, characterized in that: The liquid storage tank is located at the bottom gap, and the liquid storage tank is provided on the impeller surface.

5. The labyrinth seal structure with a liquid storage tank of an active disc centrifugal separator according to claim 1, characterized in that: There is one or more of the liquid storage tanks.

6. The labyrinth seal structure with a liquid storage tank of an active disc centrifugal separator according to claim 1, characterized in that: The cross-section of the liquid storage tank is V-shaped, U-shaped, ∪-shaped or inverted trapezoidal.

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