An air-tight sealing device

Abstract

The utility model discloses a kind of air-tight devices, including coaxially arranged shaft sleeve, pair of interlocking floating ring and sealing outer hoop assembly;Sealing outer hoop assembly includes outer hoop ring body and gland, and annular gas guide groove is equipped in outer hoop ring body inner side end face, and annular gas guide groove is communicated with external gas source;The inner circle end face of interlocking floating ring is evenly distributed with several meshing tooth rings along the axial direction;The outer peripheral wall of shaft sleeve is equipped with several annular pressure reduction grooves with meshing tooth ring staggered arrangement along the axial direction, and meshing tooth ring and annular pressure reduction groove form gas film gap, and gas film gap and annular gas guide groove are equipped with gas guide passage;Gas is injected into gas film gap by gas guide passage, and stable gas film is formed between annular pressure reduction groove and meshing tooth ring when shaft sleeve high-speed rotates, realize non-contact sealing.The utility model forms stable gas film between meshing tooth ring and annular pressure reduction groove by gas, realize non-contact end face sealing under high-speed working condition, reduce abrasion, prolong service life.

Description

Technical Field

[0001] This utility model relates to the field of non-contact sealing technology for high-speed rotating machinery, and in particular to an air-sealing device. Background Technology

[0002] In high-speed rotating machinery, such as centrifugal compressors and high-speed pumps, mechanical seals are usually required. The commonly used sealing method is the end-face contact design. However, end-face contact seals rely on the close contact of the friction pairs, which leads to high friction and high loss. Moreover, end-face contact seals not only affect rotational accuracy, but are also particularly unsuitable for high-speed operation. The high frictional resistance makes the end-face contact parts prone to wear, resulting in short equipment life and high maintenance costs.

[0003] Therefore, a sealing structure with both non-contact characteristics and dynamic axial displacement compensation is designed to be suitable for use in high-speed rotating equipment. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides an airtight device suitable for equipment that requires high-speed rotation, such as centrifugal compressors and high-speed pumps.

[0005] The technical solution of this utility model is: it includes a bushing arranged coaxially, a pair of interlocking floating rings and a sealing outer hoop assembly;

[0006] The sealing outer hoop assembly includes an outer hoop ring and a pressure cap. The inner end face of the outer hoop ring is provided with an annular air guide groove, which is connected to an external air source.

[0007] The interlocking floating ring has several meshing toothed rings evenly distributed along the axial direction on the inner ring end face.

[0008] The outer peripheral wall of the bushing is provided with a plurality of annular pressure relief grooves arranged axially in a staggered manner with the meshing tooth ring, and an air film gap is formed between the meshing tooth ring and the annular pressure relief groove. An air guiding channel is provided between the air film gap and the annular air guiding groove.

[0009] Gas is injected into the gas film gap through the gas guide channel. When the bushing rotates at high speed, a stable gas film is formed between the annular pressure reducing groove and the meshing toothed ring, thus achieving non-contact sealing.

[0010] Furthermore, it also includes a dynamic compensation module, which includes a floating compensation ring composed of multiple independent sector blocks and a preload spring coaxially sleeved on the outer ring of the floating compensation ring.

[0011] The floating compensation ring has tapered mating surfaces between its two axial end faces and the corresponding interlocking floating rings.

[0012] When the bushing undergoes axial displacement, the radial displacement of the floating compensation ring is converted into the axial compensation displacement of the interlocking floating ring through the tapered mating surface, maintaining a constant air film gap.

[0013] Furthermore: a radially arranged annular buffer cavity is provided between the floating compensation ring and the interlocking floating ring; the interlocking floating ring is provided with a plurality of first air guide holes, the two ends of which in the radial direction are respectively connected to the annular air guide groove and the annular buffer cavity; the floating compensation ring is provided with a radially extending second air guide hole, the two ends of which are respectively connected to the annular buffer cavity and the air film gap, and the air guide channel is composed of the first air guide hole, the annular buffer cavity and the second air guide hole.

[0014] Furthermore: a reinforced steel frame is embedded on the inner side of the outer ring of the interlocking floating ring, and a through hole communicating with the first air guide hole is opened on the reinforced steel frame.

[0015] Furthermore: the inner end face of the outer ring body is provided with two sets of annular air guide grooves at intervals, the two sets of annular air guide grooves are connected along the axial direction, one set of annular air guide grooves is connected to an external air source through an air inlet hole opened on the pressure cap; the other set of annular air guide grooves is connected to the first air guide through hole.

[0016] Furthermore, it also includes a gap adjustment mechanism, which comprises a pair of conical clamping plates and an axially penetrating bolt group;

[0017] The bolt assembly passes sequentially through a conical clamping plate on one side, an interlocking floating ring on one side, a floating compensation ring, an interlocking floating ring on the other side, and a conical clamping plate on the other side. When the bolt assembly is tightened, the conical clamping plate contracts axially and causes the interlocking floating ring to elastically deform in order to adjust the air film gap.

[0018] Furthermore: the outer peripheral wall of the bushing is provided with an annular positioning groove, and the inner ring of the conical clamp is provided with a positioning disc;

[0019] During initial adjustment, the positioning vane engages with the annular positioning groove to lock the preset air film gap. When the bushing rotates at high speed, the positioning vane disengages from the annular positioning groove.

[0020] Furthermore, the inner end face of the pressure cap is provided with a sealing flange, and the sealing flange is sealed to the inner end face of the outer hoop body by an inner O-ring.

[0021] The beneficial technical effects of this utility model are: by introducing gas to form a stable gas film between the meshing toothed ring and the annular pressure reducing groove, non-contact end face sealing is achieved under high-speed operating conditions, which greatly reduces wear and extends service life. It is especially suitable for high-speed rotating equipment such as centrifugal compressors and high-speed pumps.

[0022] The dynamic compensation module uses a floating compensation ring, a preload spring, and a tapered mating surface to convert the axial displacement of the bushing caused by thermal expansion or vibration into the radial displacement of the floating compensation ring driven by gas pressure. The tapered mating surface's inclined transmission mechanism automatically converts this displacement into the axial compensation displacement of the interlocking floating ring, thus dynamically maintaining a constant gas film gap and ensuring that the sealing reliability is not affected by changes in operating conditions.

[0023] The air film gap can be precisely and conveniently adjusted and set using a conical clamp and bolt assembly.

[0024] The effective gas flow path enables uniform gas distribution, buffering and pressure stabilization, and precise supply, providing a reliable guarantee for the formation of a stable and uniform gas film and improving sealing performance.

[0025] The overall structure provides an advanced shaft sealing solution with long service life, high reliability, and strong adaptability for high-speed rotating equipment through non-contact sealing, dynamic gap compensation, and stable airflow management. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the first end face of the overall structure of this utility model;

[0027] Figure 2 This is a schematic diagram of the second end face of the overall structure of this utility model;

[0028] Figure 3 This is a cross-sectional view of the overall structure of this utility model;

[0029] Figure 4 This is a schematic diagram of the axially connected structure of the two sets of annular air guide grooves of this utility model;

[0030] Figure 5 This is an exploded view of the overall structure of this utility model;

[0031] The components include: 1. Bushing; 1a. Annular pressure relief groove; 1b. Annular positioning groove; 2. Interlocking floating ring; 2a. Meshing toothed ring; 3. Outer hoop ring body; 3a. Annular air guide groove; 4. Pressure cap; 4a. Sealing flange; 4b. Air inlet; 5. Fastening bolt; 6. Inner O-ring seal; 7. First air guide hole; 8. Floating compensation ring; 9. Preload spring; 10. Second air guide hole; 11. Conical clamping plate; 12. Bolt assembly; 13. Reinforced steel frame; 14. Positioning rotary plate. Detailed Implementation

[0032] In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0033] like Figures 1 to 5 As shown, the gas sealing device of this utility model includes a coaxially arranged bushing 1, a pair of interlocking floating rings 2, a sealing outer hoop assembly, a dynamic compensation module, and a gap adjustment mechanism.

[0034] The sealing outer ring assembly includes an outer ring body 3 and a pressure cap 4. The inner end face of the outer ring body 3 is provided with an annular air guiding groove 3a, which is connected to an external air source. The pressure cap 4 is fixedly connected to the outer ring body 3 by axial fastening bolts 5. Furthermore, the inner end face of the pressure cap 4 is provided with a sealing flange 4a that mates with the inner end face of the outer ring body 3. The sealing flange 4a and the inner end face of the outer ring body 3 are sealed by an inner O-ring seal 6.

[0035] The outer peripheral wall of the bushing 1 is provided with an annular pressure relief groove 1a.

[0036] The inner ring end face of the interlocking floating ring 2 has several meshing toothed rings 2a evenly distributed along the axial direction. The meshing toothed rings 2a and the annular pressure reducing groove 1a are staggered along the axial direction of the bushing 1, and an air film gap is formed between the meshing toothed rings 2a and the annular pressure reducing groove 1a. An air guiding channel is provided between the air film gap and the annular air guiding groove 3a. Gas is injected into the air film gap through the air guiding channel, and a stable air film is formed between the annular pressure reducing groove 1a and the meshing toothed rings 2a when the bushing 1 rotates at high speed, so as to achieve non-contact sealing.

[0037] Preferably, the inner end face of the outer ring body 3 is provided with two sets of annular air guiding grooves 3a that are axially connected. One set of annular air guiding grooves 3a is connected to an external air source through an air inlet 4b opened on the pressure cap 4. Several first air guiding holes 7 are evenly distributed along the circumference on the interlocking floating ring 2. The airflow in the other set of annular air guiding grooves 3a is evenly distributed along the circumference and then enters the first air guiding hole 7 radially.

[0038] The dynamic compensation module includes a floating compensation ring 8 composed of multiple independent sector blocks and a preload spring 9 coaxially sleeved on the outer ring of the floating compensation ring 8. The preload spring 9 provides a radially inward elastic preload force and forms a dynamic balance with the gas pressure. Each independent sector block of the floating compensation ring 8 can float slightly radially under the action of the elastic preload force of the preload spring 9. The two end faces of the floating compensation ring 8 along the axial direction are respectively provided with tapered mating surfaces between them and the paired interlocking floating rings 2. When the bushing 1 undergoes axial displacement due to thermal expansion or vibration, the sector blocks of the floating compensation ring 8 generate radial displacement under the action of gas pressure. Through the inclined transmission mechanism of the tapered mating surfaces, the radial displacement of the floating compensation ring 8 is converted into the axial compensation displacement of the interlocking floating rings 2, keeping the gas film gap between the meshing toothed ring 2a and the annular pressure reducing groove 1a constant.

[0039] The floating compensation ring 8 and the interlocking floating ring 2 have an annular buffer cavity in the radial direction. The two ends of the first air guide hole 7 in the radial direction are respectively connected to the annular air guide groove 3a and the annular buffer cavity. When the gas diffuses into the annular buffer cavity through the first air guide hole 7, it achieves buffering and pressure stabilization in the annular buffer cavity.

[0040] The floating compensation ring 8 is provided with a second air guide hole 10 extending radially. The two ends of the second air guide hole 10 in the radial direction are respectively connected to the annular buffer cavity and the air film gap. The air guide channel is composed of a first air guide hole 7, an annular buffer cavity and a second air guide hole 10.

[0041] The gap adjustment mechanism includes a pair of conical clamping plates 11 and a bolt group 12 extending axially. The pair of conical clamping plates 11 are located on the outer side of the interlocking floating ring 2 along the axial direction, and the axial end faces of the conical clamping plates 11 are fitted and engaged with the axial end faces of the interlocking floating ring 2. The bolt group 12 passes through the corresponding bolt holes of the following components in sequence along the axial direction: the conical clamping plate 11 on one side, the interlocking floating ring 2 on one side, the floating compensation ring 8, the interlocking floating ring 2 on the other side, and the conical clamping plate 11 on the other side.

[0042] A reinforced steel frame 13 is embedded on the inner side of the outer ring of the interlocking floating ring 2. The reinforced steel frame 13 has a through hole communicating with the first guide through hole. The bolt group 12 drives the conical clamping plates 11 on both sides to contract axially, causing the interlocking floating ring 2 to undergo elastic deformation, thereby adjusting the gas film gap between the meshing toothed ring 2a and the annular pressure reducing groove 1a. The reinforced steel frame 13 provides solid internal support for the interlocking floating rings 2 on both sides, enhancing their overall structural rigidity and resistance to deformation, especially maintaining shape stability when subjected to gas pressure and the preload of the bolt group 12.

[0043] Furthermore, the outer peripheral wall of the bushing 1 is provided with an annular positioning groove 1b, which cooperates with the positioning disc 14 on the inner ring of the conical clamping plate 11. In the initial adjustment stage, the bolt group 12 drives the conical clamping plate 11 to axially contract, forcing the interlocking floating ring 2 to undergo elastic deformation until the positioning disc 14 on the inner ring of the conical clamping plate 11 is engaged in the annular positioning groove 1b and locked, thus completing the preset initial air film gap adjustment; after the entire air sealing device has completed the initial adjustment and is installed on the equipment, the positioning disc 14 needs to be disengaged from the annular positioning groove 1b to prevent the positioning disc 14 from contacting and wearing during the high-speed rotation of the bushing 1.

[0044] In this embodiment, the gas flow path is as follows: gas from an external gas source enters two sets of annular gas guide grooves 3a sequentially through the air inlet, and then radially enters the annular buffer chamber along several first gas guide holes 7, where the gas velocity is reduced and the pressure is buffered. Finally, the gas is injected radially into the gas film gap through the second gas guide hole 10 on the floating compensation ring 8. Under the condition of high-speed rotation of the bushing 1, a stable gas film is formed between the annular pressure reducing groove 1a and the stationary meshing toothed ring 2a, achieving non-contact sealing, greatly reducing wear and extending service life, and is particularly suitable for high-speed rotating equipment such as centrifugal pumps.

[0045] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. An airtight sealing device, characterized in that: It includes a coaxially arranged bushing (1), a pair of interlocking floating rings (2), and a sealing outer hoop assembly; The sealing outer hoop assembly includes an outer hoop ring (3) and a pressure cap (4). The inner end face of the outer hoop ring (3) is provided with an annular air guide groove (3a), which is connected to an external air source. Several meshing toothed rings (2a) are evenly distributed along the axial direction on the inner ring end face of the interlocking floating ring (2). The outer peripheral wall of the bushing (1) is provided with a plurality of annular pressure relief grooves (1a) arranged axially intersecting with the meshing toothed ring (2a), and an air film gap is formed between the meshing toothed ring (2a) and the annular pressure relief groove (1a), and an air guiding channel is provided between the air film gap and the annular air guiding groove (3a). Gas is injected into the gas film gap through the gas guide channel. When the bushing (1) rotates at high speed, a stable gas film is formed between the annular pressure reducing groove (1a) and the meshing toothed ring (2a), thus achieving non-contact sealing.

2. The gas-tight device according to claim 1, characterized in that: It also includes a dynamic compensation module, which includes a floating compensation ring (8) composed of multiple independent sector blocks and a preload spring (9) coaxially sleeved on the outer ring of the floating compensation ring (8). The floating compensation ring (8) has tapered mating surfaces on both ends along the axial direction and the corresponding interlocking floating ring (2); When the bushing (1) undergoes axial displacement, the radial displacement of the floating compensation ring (8) is converted into the axial compensation displacement of the interlocking floating ring (2) through the tapered mating surface, thus maintaining a constant air film gap.

3. The gas-tight device according to claim 2, characterized in that: The floating compensation ring (8) and the interlocking floating ring (2) have an annular buffer cavity in the radial direction; the interlocking floating ring (2) is provided with a plurality of first air guide holes (7), the two ends of the first air guide holes (7) in the radial direction are respectively connected to the annular air guide groove (3a) and the annular buffer cavity; the floating compensation ring (8) is provided with a radially extending second air guide hole (10), the two ends of which are respectively connected to the annular buffer cavity and the air film gap, and the air guide channel is composed of the first air guide hole (7), the annular buffer cavity and the second air guide hole (10).

4. The gas-tight device according to claim 3, characterized in that: The inner side of the outer ring of the interlocking floating ring (2) is fitted with a reinforced steel frame (13), and the reinforced steel frame (13) has a through hole that communicates with the first air guide hole (7).

5. The gas-tight device according to claim 3, characterized in that: The inner end face of the outer ring body (3) is provided with two sets of annular air guide grooves (3a) at intervals. The two sets of annular air guide grooves (3a) are connected along the axial direction. One set of annular air guide grooves (3a) is connected to an external air source through an air inlet (4b) opened on the pressure cap (4); the other set of annular air guide grooves (3a) is connected to the first air guide through hole (7).

6. The gas-tight device according to claim 1, characterized in that: It also includes a gap adjustment mechanism, which includes a pair of conical clamps (11) and an axially penetrating bolt group (12). The bolt group (12) passes through the conical clamping plate (11) on one side, the interlocking floating ring (2) on one side, the floating compensation ring (8), the interlocking floating ring (2) on the other side, and the conical clamping plate (11) on the other side in sequence. When the bolt group (12) is tightened, the conical clamping plate (11) contracts axially and drives the interlocking floating ring (2) to elastically deform in order to complete the adjustment of the air film gap.

7. The gas-tight device according to claim 6, characterized in that: The bushing (1) has an annular positioning groove (1b) on its outer peripheral wall and a positioning rotary plate (14) on its inner ring. During initial adjustment, the positioning blade (14) is engaged in the annular positioning groove (1b) to lock the preset air film gap. When the bushing (1) rotates at high speed, the positioning blade (14) is disengaged from the annular positioning groove (1b).

8. The gas-tight device according to claim 1, characterized in that: The inner end face of the pressure cap (4) is provided with a sealing flange (4a), and the sealing flange (4a) is sealed to the inner end face of the outer hoop body (3) by an inner O-ring (6).

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