Sugarcoated haw type centrifugal flow choking type liquid self-impact sealing structure

Abstract

The invention discloses a sugarcoated haw type centrifugal choked flow type liquid self-impact sealing structure which comprises a movable ring and a static ring, the static ring is divided into a first static semi-ring and a second static semi-ring, the movable ring is assembled between the first static semi-ring and the second static semi-ring, the inner side face of the first static semi-ring is an inclined face, and the outer side face of the second static semi-ring is an inclined face. The inner side face of the second static semi-ring is a vertical face, the vertical face is provided with a plurality of second suspension columns, and corresponding to the static semi-ring, one side face of the movable ring is a slope and provided with a plurality of U-shaped grooves, and the other side face of the movable ring is a vertical face and provided with a plurality of suspension column grooves. A sealing gap formed by mutual matching of the first static semi-ring, the movable ring and the first suspension column is a self-impact bent flow channel, a sealing gap formed by mutual matching of the second static semi-ring and the movable ring is a centrifugal bent flow channel, and a sealing gap formed by mutual matching of the second static semi-ring, the second suspension column and the movable ring is a labyrinth bent flow channel. The self-impact bending flow channel forms a self-impact blocking structure, the centrifugal bending flow channel forms a centrifugal blocking structure, and the labyrinth bending flow channel is communicated to form a wall face impact blocking structure.

Description

Technical Field

[0001] The invention belongs to the technical field of sealing, and in particular relates to a candied haws-shaped centrifugal flow-blocking liquid self-impact sealing structure. Background Art

[0002] There are still many problems with non-contact liquid sealing technology, which are manifested as: the existence of straight-through leakage channels, resulting in large leakage and low sealing efficiency (such as liquid film and spiral seals); excessive reliance on spindle speed, and loss of sealing ability during startup and shutdown (such as liquid film and spiral seals); weak adaptability to high-speed or high-pressure conditions (such as magnetic fluid seals), and drastic phase changes at high speeds leading to sealing failure (such as liquid film seals). The auxiliary devices are complex and the system stability is poor (such as liquid film and spiral seals). Currently, only the gas self-impact sealing technology has been developed, which has been proven to have the advantages of high sealing efficiency; however, this sealing method has not yet achieved the ideal effect when the sealed medium is a liquid. Compared with the properties of liquids and gases, the physical properties of liquids are very different and have unique surface and interface characteristics, which increases the difficulty of liquid sealing technology. Therefore, it is very necessary to carry out research on liquid self-impact sealing technology.

[0003] CN 118188818 The self-impact liquid seal described in A can achieve the sealing of liquid, but it is actually a new type of magnetic fluid seal. Its working principle is similar to that of magnetic fluid seal, but it is very different from the conventional blocking self-impact seal. Before working, it is necessary to inject magnetic liquid into the gap flow channel. The magnetic liquid will be retained in the sealing structure under the action of the magnetic field. The retained magnetic fluid plays a role similar to a "barrier" or an "O-ring", blocking the gap channel to achieve the purpose of sealing. However, this method has the following disadvantages: limited temperature application range (the stability of magnetic fluid will be affected at high temperature), small pressure application range (under high pressure conditions, the sealed medium will break through the magnetic fluid barrier and flush part of the magnetic fluid out of the structure, thereby affecting the sealing effect), will be disturbed by the magnetic field (there are strong magnetic conditions in industrial scenarios, and the strong magnetic field will interact with the magnetic fluid to affect the sealing effect), and small speed application range (high speed will cause the magnetic fluid to heat up, which may cause the magnetic fluid to demagnetize, and at high speed, the two liquids will mix at the contact interface between the sealed liquid and the magnetic fluid, resulting in contamination of the sealed liquid, while reducing the purity of the magnetic fluid and weakening the sealing effect). The conventional blocking self-impact seal does not require the additional introduction of magnetic fluid and only relies on its flow channel structure to achieve the sealing of the liquid, which can overcome the above-mentioned defects.

[0004] Through theoretical research, we found that the Tesla valve self-impact structure of each level of gas self-impact sealing has the following prominent problems when used to seal liquids: the impact effect is very weak when the pressure difference is small, that is, far away from the high-pressure side, its impact blocking and leakage suppression effect is no longer significant; the radial gap will cause the fluid in the sealing gap to flow to the outer diameter side under the influence of centrifugal force, which is likely to increase the risk of leakage; the sealing effect of the equal gap structure is greater than that of the equivalent straight-through gap seal (the total cross-sectional area and length of the microchannel are equal to the cross-sectional area and length of the self-impact structure, respectively), and the leakage is greater. Summary of the invention

[0005] Based on the problems existing in the background technology, the present invention proposes a candied haws-shaped centrifugal resistance-type liquid self-impact sealing structure. The sealing technology of the present invention is no longer overly dependent on the spindle speed, but can take advantage of the speed to achieve more efficient sealing, while taking into account the characteristics of simple structure and stable performance.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A candied-haws-shaped centrifugal flow-blocking liquid self-impact sealing structure, the liquid self-impact sealing structure comprises a dynamic ring and a static ring, the static ring is divided into a first static semi-ring and a second static semi-ring, the dynamic ring is assembled between the first static semi-ring and the second static semi-ring, the inner side surface of the first static semi-ring is an inclined surface, and the inclined surface is stepped and provided with a plurality of U-shaped grooves, the inner side surface of the second static semi-ring is a vertical surface, and a plurality of second suspension columns are arranged on the vertical surface, corresponding to the static semi-ring, one side surface of the dynamic ring is an inclined surface and is provided with a plurality of U-shaped grooves, and the other side surface is a vertical surface and is provided with a plurality of suspension column grooves, the sealing gap formed by the cooperation of the first static semi-ring, the dynamic ring and the first suspension column is a self-impact bending flow channel, the sealing gap formed by the cooperation of the second static semi-ring and the dynamic ring is a centrifugal bending flow channel, the sealing gap formed by the cooperation of the second static semi-ring, the second suspension column and the dynamic ring is a labyrinth bending flow channel, the self-impact bending flow channel constitutes a self-impact blocking structure, the centrifugal bending flow channel constitutes a centrifugal blocking structure, the labyrinth bending flow channel constitutes a wall impact blocking structure, and each flow channel is connected in sequence.

[0007] Furthermore, the impact blocking structure is divided into a main flow channel and an auxiliary flow channel, the main flow channel is a portion inclined from the impact bending flow channel, and the auxiliary flow channel is a flow channel formed around the first suspension column.

[0008] Furthermore, the width of the main flow channel is twice the width of the auxiliary flow channel, and the inclination angle of the main flow channel of the self-impact bending flow channel is 135°.

[0009] Furthermore, the first suspension column is fixedly connected to the first static semi-ring by screws.

[0010] Furthermore, the static semi-ring and the dynamic ring are made of hard materials, and the suspension column is made of soft materials.

[0011] Furthermore, the first static half ring and the first static half ring are connected by a bolt group, and the sealing gasket between the first static half ring and the first static half ring is compressed by the bolt group.

[0012] Furthermore, the gap between the moving ring and the shaft is sealed by an O-ring, the moving ring is axially positioned by a positioning retaining ring, the moving ring is fixed to the shaft by a set screw, and the circumferential shear force of the moving ring during rotation is borne by a key.

[0013] The following beneficial effects can be obtained through the above technical solution: According to CFD numerical calculation, the present invention has the following advantages over traditional similar sealing structures: Compared with gap seals, the sealing structure of the present invention has better sealing ability than gap seals regardless of pressure and speed; compared with labyrinth gap seals (different from labyrinth seals), when the medium used is engine oil, the sealing ability of the sealing structure of the present invention is better than labyrinth gap seals regardless of pressure and speed; and when there is a speed, the sealing ability is better than labyrinth gap seals regardless of the medium; and when the speed is zero, the pressure is lower than 2MPa, and the medium is water, the sealing ability is better than labyrinth gap seals. Compared with spiral seals, the sealing structure of the present invention is not limited by the direction of rotation, and when the spindle speed is within 1000r / min and the medium is water, the medium leakage of the sealing structure is lower than that of spiral seals; when the vehicle is parked, the sealing ability is better than that of spiral seals. Compared with the self-impact structure imitating Tesla valve wings, the structure is more economical to manufacture.

[0014] The non-contact seal of the present invention will not produce wear during normal operation, has low power consumption, and is suitable for use in high-speed rotation occasions. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of the liquid self-impact seal of the present invention.

[0016] Figure 2 It is a schematic diagram of the assembly of the present invention.

[0017] Figure 3 This is a diagram of the working principles of several sealing gaps.

[0018] Figure 4 It is a schematic diagram of the structure of the coordination of the 135° inclination angle and the straight channel.

[0019] Figure 5 It is a structural diagram of the coordination of a 90° inclination angle and a straight channel.

[0020] Figure 6 It is the pressure distribution cloud diagram of the 135° inclination angle-straight channel liquid self-impact sealed microchannel at 10000r / min.

[0021] Figure 7It is the pressure distribution cloud diagram of the self-impact sealed microchannel of the straight channel liquid at a 90° inclination angle at 10000r / min.

[0022] Figure 8 It is the pressure distribution cloud diagram of the 135° inclination angle-maze channel liquid self-impact sealing microchannel at 10000r / min.

[0023] Fig. 9 It is the pressure distribution cloud diagram of the self-impact sealed microchannel of the straight channel liquid at 135° inclination angle at 0r / min.

[0024] Fig.10 It is the pressure distribution cloud diagram of the self-impact sealed microchannel of the straight channel liquid with a 90° inclination angle at 0 r / min.

[0025] Fig.11 It is the pressure distribution cloud diagram of the self-impact sealed microchannel of the labyrinth channel with an inclination angle of 135° at 0 r / min.

[0026] In the figure: In the figure: 1, shaft; 2, first static half ring; 3, first suspension column; 4, screw; 5, positioning retaining ring; 6, O-ring; 7, second static half ring, 8, set screw, 9, key, 10, moving ring, 11, second suspension column, 12, sealing gasket, 13, bolt group, 14, centrifugal bending flow channel, 15, labyrinth bending flow channel, 16, self-impact bending flow channel. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings: like Figure 1-11 As shown, a candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure, the liquid self-impact sealing structure comprises a dynamic ring and a static ring, characterized in that: the static ring is divided into a first static semi-ring and a second static semi-ring, the dynamic ring is assembled between the first static semi-ring and the second static semi-ring, the inner side surface of the first static semi-ring is an inclined surface, the inclined surface is stepped and a plurality of U-shaped grooves are arranged, the inner side surface of the second static semi-ring is a vertical surface, a plurality of second suspension columns are arranged on the vertical surface, corresponding to the static semi-ring, one side surface of the dynamic ring is an inclined surface and a plurality of U-shaped grooves are arranged, and the other side surface is vertical A plurality of suspension column grooves are arranged on the surface, the sealing gap formed by the cooperation of the first static semi-ring, the dynamic ring and the first suspension column is a self-impact bending flow channel 16, the sealing gap formed by the cooperation of the second static semi-ring and the dynamic ring is a centrifugal bending flow channel 14, the sealing gap formed by the cooperation of the second static semi-ring, the second suspension column and the dynamic ring is a labyrinth bending flow channel 15, the self-impact bending flow channel constitutes a self-impact blocking structure, the centrifugal bending flow channel constitutes a centrifugal blocking structure, the labyrinth bending flow channel constitutes a wall impact blocking structure, and each flow channel is connected in sequence.

[0028] The self-impinging blocking structure is divided into a main flow channel and an auxiliary flow channel. The main flow channel is the inclined part in the self-impinging bent flow channel, and the auxiliary flow channel is the flow channel formed around the suspension post.

[0029] The width of the main flow channel is twice that of the auxiliary flow channel, and the inclination angle of the self-impinging bent flow channel is 135°.

[0030] The first suspension post and the first static half-ring are fixedly connected by screws.

[0031] The static half-ring and the moving ring are made of hard materials, and the suspension post is made of soft materials.

[0032] The first static half-ring and the first static half-ring are connected by a bolt group, and the gasket between the first static half-ring and the first static half-ring is compressed by the bolt group.

[0033] The gap between the moving ring and the shaft is sealed by an O-ring. The moving ring is axially positioned by a retaining ring. The moving ring is fixed on the shaft by a set screw, and the key bears the circumferential shear force of the moving ring during rotation. Embodiment

[0034] Figure 1 and Figure 2 As shown, in this embodiment, a "tanghulu"-type centrifugal choke liquid self-impinging seal structure is designed, which consists of a shaft 1, a first static half-ring 2, a second static half-ring 7, a moving ring 10, and a first suspension post 3, which cooperate with each other to form a sealing gap. Among them, Figure 1 The right side surface of the first static half-ring 2 is inclined, and its inclination angle is preferably 135°. The left side surface of the moving ring corresponding to the first static half-ring 2 is also inclined. A number of U-shaped grooves are provided on the inclined surfaces of the first static half-ring 2 and the moving ring 10. The U-shaped grooves on the first static half-ring 2 and the U-shaped grooves on the moving ring 10 cooperate to form a first suspension post cavity, into which a first suspension post is inserted. The first suspension post 3 is fixed by screws 4. The left side of the second static half-ring 7 is a vertical surface, and a number of second suspension posts 11 are installed on the vertical surface. Correspondingly, a number of second suspension post grooves are provided on the right vertical surface of the moving ring 10. Through the above assembly relationship, the first static half-ring, the moving ring, and the first suspension post cooperate with each other to form a self-impinging blocking structure. The sealing gap part in the self-impinging blocking structure is a self-impinging bent flow channel. The second static half-ring and the moving ring cooperate with each other to form a centrifugal blocking structure. The sealing gap part in the centrifugal blocking structure is a centrifugal bent flow channel. The second static half-ring, the second suspension post, and the moving ring cooperate with each other to form a wall-impinging blocking structure. The sealing gap part in the wall-impinging blocking structure is a labyrinth bent flow channel. The self-impinging bent flow channel, the centrifugal bent flow channel, and the labyrinth bent flow channel are connected in sequence, and the three flow channels are connected to form a shape similar to the Chinese character "ji". One end of the labyrinth bent flow channel is communicated with the atmospheric environment, and one end of the self-impinging bent flow channel is communicated with the high-pressure liquid medium part.

[0035] The self-impact blocking structure is divided into a main flow channel and an auxiliary flow channel. The main flow channel is an inclined part of the self-impact bending flow channel, and the auxiliary flow channel is a flow channel formed around the first suspension column.

[0036] The first static half ring 2 and the second static half ring 7 are connected by a bolt group 13, and the sealing gasket 12 is compressed by the bolt group 13 to prevent leakage between the first static half ring 2 and the second static half ring 7. The axial gap size can be adjusted by adjusting the bolt. The gap between the dynamic ring 10 and the shaft 1 is sealed by an O-ring 6. The dynamic ring 10 is axially positioned by a positioning retaining ring 5 to prevent the dynamic ring 10 from moving to the left. The dynamic ring 5 is completely fixed by a set screw 8, and the key 9 bears the circumferential shear force of the dynamic ring 10 during rotation. The suspension column 3 is fixed to the first static half ring 2 by a screw 4. The first static half ring 2, the second static half ring 7, and the dynamic ring 10 are made of hard materials, and the suspension column is made of soft material.

[0037] Figure 3 Several groups of working principle diagrams of sealing gaps are shown, and the sealing structure of the present invention is obtained by upgrading the sealing structure unit design: Figure 3 (a) is a traditional straight channel seal, which mainly relies on the flow resistance along the flow channel to limit the flow. The longer the channel, the less leakage. This form has a simple structure, but the throttling efficiency is very low. Figure 3 (b) is a self-impacting unit imitating the Tesla valve wing shape. It uses the one-way conduction characteristics of the Tesla valve, that is, through the collision of the two auxiliary flow channels, the flow velocity of the fluid is reduced, thereby achieving flow limitation. In principle, this form has a higher throttling efficiency, but the processing cost is high; Figure 3 (c) is a key-shaped self-impact unit with a straight main flow channel of equal cross-section. After upgrading the wing-shaped suspension column to a key-shaped suspension column, the processing cost can be reduced by more than 60%. However, if the main flow channel and auxiliary flow channel of the same width are used, the gas can be effectively sealed, but when applied to liquid media, the sealing effect is poor; Figure 3 (d) is a key-shaped variable cross-section straight-through main channel self-impact unit, which analogizes the flow field to an electric field. The equal cross-section straight-through main channel self-impact unit is similar to a parallel circuit. When the width of the auxiliary flow channel is 1 / 2 of the width of the main channel, the flow resistance of the "parallel" structural unit can be approximately equal to the flow resistance of the "series" structural unit (i.e., straight channel) with the same total cross-sectional area and length. In fact, according to the numerical simulation results, compared with the equivalent straight channel structure, the key-shaped self-impact sealing structural unit can reduce the leakage rate by more than 35%; Figure 3(e) is the self-impact unit of the main channel of the key-deformed cross-section inclined channel of the sealing structure of the present invention. The main channel is designed as an inclined channel. In this way, on the one hand, the inclined wall surface can make the centrifugal force produce a component force that hinders the flow of the flow field, and the larger the inclination angle, the larger the component force that hinders the flow, and the less leakage of the flow field to the outlet side of the external environment. On the other hand, the flow channel can be extended by adjusting the inclination angle, thereby increasing the resistance along the way.

[0038] Under the premise that the optimization design has not been carried out, it is preliminarily obtained through numerical simulation that the main channel width is 0.1mm, the auxiliary channel width is 0.05mm, the unit level is 4, and the inclination angle is 135° ( Figure 2 ), the axial total dimension is 53.5mm, and the maximum diameter is 118.2mm. The higher the speed, the less leakage, and even reverse pumping effect. For water medium, standard leakage (≤5ml / h) can be achieved at around 6000r / min, and zero leakage can be achieved at around 7000r / min. Among them, the inclination angle should be greater than or equal to 90° (90° is Figure 5 As shown in the figure, the larger the inclination angle, the smaller the leakage at low speed, but the weaker the pumping effect at high speed. Therefore, for low speed occasions, the number of sealing stages can be increased, or the inclination angle can be increased, or the right radial clearance can be designed as a labyrinth clearance (such as Figure 2 ). When the inclination angle is 90°, the suspension column 3 and the first static half ring 2 are subject to structural interference, and it is not convenient to fix them with screws 4. Here, welding, gluing, etc. are required to fix the suspension column 3 and the first static half ring 2. Figure 6-Figure 8 From the pressure distribution cloud diagram at 10000r / min, it can be seen that the liquid film pressure increases in the radial direction, that is, a high-pressure area is formed on the outer diameter side, which effectively suppresses the leakage of the liquid medium from the inlet side to the outlet side. Figure 9-11 As shown in the 0r / min pressure distribution cloud diagram, the liquid film pressure decreases step by step. This is because the structure of the present invention combines the blocking effects of fluid impact, viscosity, structure, centrifugation, centrifugal inhibition, etc., thereby achieving the throttling and leakage suppression effect. Figure 1 As shown in the figure, impact blockage is mainly achieved by the self-impact structure and the labyrinth gap structure; viscous blockage is reflected in the entire microchannel; structural blockage includes the arc-shaped flow channel and the contraction flow channel structure of the self-impact structure, the bending structures on both sides of the centrifugal structure, and the bending flow channel structure of the labyrinth gap, among which the arc-shaped flow channel of the self-impact structure, the bending structures on both sides of the centrifugal structure and the bending flow channel structure of the labyrinth gap all have significant wall impact blockage effect; centrifugal blockage is provided by the centrifugal structure with a larger radius; centrifugal suppression blockage is achieved by the inclination angle of the main flow channel of the self-impact structure.

[0039] The above are all preferred embodiments of the present invention. For ordinary technicians in this technical field, without departing from the principle of the present invention, various equivalent modifications to the present invention belong to the protection scope of the claims attached to this application.

Claims

1. A candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure, the liquid self-impact sealing structure comprises a dynamic ring and a static ring, characterized in that: The static ring is divided into a first static half ring and a second static half ring, and a dynamic ring is assembled between the first static half ring and the second static half ring, the inner side surface of the first static half ring is an inclined surface, and the inclined surface is stepped to provide a plurality of U-shaped grooves and a plurality of first suspension columns, the inner side surface of the second static half ring is a vertical surface, and a plurality of second suspension columns are provided on the vertical surface, corresponding to the static half ring, one side surface of the dynamic ring is an inclined surface and is provided with a plurality of U-shaped grooves, and the other side surface is a vertical surface and is provided with a plurality of suspension column grooves, the sealing gap formed by the cooperation of the first static half ring, the dynamic ring and the first suspension column is a self-impact bending flow channel, the sealing gap formed by the cooperation of the second static half ring and the dynamic ring is a centrifugal bending flow channel, the sealing gap formed by the cooperation of the second static half ring, the second suspension column and the dynamic ring is a labyrinth bending flow channel, the self-impact bending flow channel constitutes a self-impact blocking structure, the centrifugal bending flow channel constitutes a centrifugal blocking structure, the labyrinth bending flow channel constitutes a wall impact blocking structure, and each flow channel is connected in sequence.

2. The candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 1, characterized in that: The self-impact blocking structure is divided into a main flow channel and an auxiliary flow channel. The main flow channel is an inclined portion of the self-impact bending flow channel, and the auxiliary flow channel is a flow channel formed around the first suspension column.

3. The candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 2, characterized in that: The width of the main flow channel is twice the width of the auxiliary flow channel, and the inclination angle of the main flow channel of the self-impact bending flow channel is 135°.

4. The candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 1, characterized in that: The first suspension column is fixedly connected to the first static semi-ring by screws.

5. A candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 1 or 4, characterized in that: The static half ring and the dynamic ring are made of hard materials, and the suspension column is made of soft materials.

6. The candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 1, characterized in that: The first static half ring and the first static half ring are connected by a bolt group, and the sealing gasket between the first static half ring and the first static half ring is compressed by the bolt group.

7. The candied-fruit-shaped centrifugal flow-blocking liquid self-impact sealing structure according to claim 1, characterized in that: The gap between the moving ring and the shaft is sealed by an O-ring, the moving ring is axially positioned by a positioning retaining ring, the moving ring is fixed to the shaft by a set screw, and the key bears the circumferential shear force of the moving ring during rotation.

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