Sealing structure and screw compressor

Abstract

The embodiment of the utility model provides a sealing structure and a screw compressor. The sealing structure comprises a sealing seat, a fixing assembly, a magnetic conduction shaft sleeve, a magnetic fluid sealing assembly and a gas sealing assembly. The sealing seat is provided with an accommodating space, and a first air inlet channel and a first air outlet channel which are communicated with the accommodating space; the fixing assembly is connected with the sealing seat; the magnetic conductive shaft sleeve and the magnetic fluid sealing assembly are connected with the fixing assembly. The magnetofluid sealing assembly is in close contact with the inner wall of the sealing seat and forms magnetofluid sealing with the magnetic conductive shaft sleeve; the gas sealing assembly is located on one side, in the axial direction of the magnetic conductive shaft sleeve, of the magnetic fluid sealing assembly, an annular gas flowing space is defined by the gas sealing assembly, the sealing base, the magnetic conductive shaft sleeve, the fixing assembly and the magnetic fluid sealing assembly, and the annular gas flowing space communicates with the first gas inlet channel and the first gas outlet channel to form a gas sealing channel. The sealing device is more reliable in sealing and can be well applied to sealing of high-risk and high-corrosivity process gas.

Description

Technical Field

[0001] This utility model relates to the field of sealing technology, and in particular to a sealing structure and a screw compressor. Background Technology

[0002] Screw compressors offer advantages such as high reliability, simple operation and maintenance, and stable operation, making them widely used in manufacturing, energy, and other fields. Screw compressors in related technologies typically employ three types of mechanical seals: single-end mechanical seals, flushed double-end mechanical seals, and double-end dry gas mechanical seals. However, due to their inherent structural characteristics, these three types of mechanical seals suffer from low sealing reliability and short seal life, making them unsuitable for sealing highly hazardous and corrosive process gases. Utility Model Content

[0003] The purpose of this utility model embodiment is to provide a sealing structure and a screw compressor to improve the sealing reliability of the sealing structure, thereby increasing its service life. The specific technical solution is as follows:

[0004] An embodiment of the first aspect of this application provides a sealing structure, comprising a sealing seat, a fixing component, a magnetically conductive sleeve, a magnetic fluid sealing component, and a gas sealing component. The sealing seat has a receiving space; the sealing seat is provided with a first air inlet channel and a first air outlet channel communicating with the receiving space; the fixing component is disposed within the receiving space and connected to the sealing seat; the magnetically conductive sleeve is disposed within the receiving space and connected to the fixing component; the magnetic fluid sealing component is disposed between the outer wall of the magnetically conductive sleeve and the inner wall of the sealing seat, and is connected to the fixing component; the magnetic fluid sealing component is in close contact with the inner wall of the sealing seat and forms a magnetic fluid seal with the magnetically conductive sleeve; the gas sealing component is disposed between the outer wall of the magnetically conductive sleeve and the inner wall of the sealing seat, located on one side of the magnetic fluid sealing component in the axial direction of the magnetically conductive sleeve; the gas sealing component, together with the sealing seat, the magnetically conductive sleeve, the fixing component, and the magnetic fluid sealing component, encloses an annular gas flow space, which communicates with the first air inlet channel and the first air outlet channel respectively, forming a gas sealing channel.

[0005] In some embodiments of this application, the gas sealing assembly includes: a split labyrinth sealing member, a first sealing member, and a second sealing member;

[0006] The split labyrinth sealing member, the first sealing member, and the second sealing member are sleeved on the outside of the magnetic guide sleeve and arranged sequentially along the axial direction of the magnetic guide sleeve towards the magnetic fluid sealing assembly, and together with the sealing seat, the magnetic guide sleeve, the fixing assembly, and the magnetic fluid sealing assembly, they form an annular gas flow space.

[0007] The outlet of the first gas inlet channel and the inlet of the first gas outlet channel are both arranged towards the connection of the first sealing member and the second sealing member, so as to make the annular gas flow space communicate with the first gas inlet channel and the first gas outlet channel respectively.

[0008] In some embodiments of the present application, the split labyrinth sealing member is in close contact with the sealing seat and fixedly connected, and a plurality of first annular sealing teeth are arranged on the side close to the magnetic conducting sleeve in sequence and at intervals along the axial direction of the magnetic conducting sleeve.

[0009] The magnetic conducting sleeve is provided with a plurality of second annular sealing teeth on the side close to the split labyrinth sealing member; the second annular sealing teeth are arranged in sequence and at intervals along the axial direction of the magnetic conducting sleeve and are engaged with the first annular sealing teeth; and the first annular sealing teeth and the second annular sealing teeth have a first gap therebetween.

[0010] In some embodiments of the present application, the first sealing member is arranged at intervals with the split labyrinth sealing member, comprising a sealing ring mounting seat and a first lip-shaped sealing ring, both of which are arranged on the outside of the magnetic conducting sleeve.

[0011] The sealing ring mounting seat has a second gap between the inner side and the magnetic conducting sleeve, the outer side is in close contact with the inner wall of the sealing seat, and the mounting groove is arranged on the side close to the magnetic fluid sealing assembly.

[0012] The first lip-shaped sealing ring is arranged in the mounting groove and presses the sealing ring mounting seat, so that the sealing ring mounting seat and the sealing seat are relatively fixed and arranged in contact with the second sealing member.

[0013] In some embodiments of the present application, the second sealing member comprises:

[0014] A second lip-shaped sealing ring is arranged on the outside of the magnetic conducting sleeve; the outer side is in close contact with the magnetic fluid sealing assembly;

[0015] A first fixing member is arranged between the first lip-shaped sealing ring and the second lip-shaped sealing ring and abuts against both of them, so that a third gap is formed between the first lip-shaped sealing ring and the second lip-shaped sealing ring, and the third gap and the second gap are communicated; the first fixing member is provided with at least two through hole structures, wherein at least one of the through hole structures is arranged towards the outlet of the first gas inlet channel and communicates the first gas inlet channel and the third gap, and at least one of the through hole structures is arranged towards the inlet of the first gas outlet channel and communicates the third gap and the first gas outlet channel.

[0016] In some embodiments of the present application, the magnetic fluid sealing assembly comprises a pole shoe member; the pole shoe member is fixedly connected with the sealing seat, comprising:

[0017] a ring-shaped permanent magnet, sleeved outside the magnetic conducting sleeve;

[0018] two pole shoes, sleeved outside the magnetic conducting sleeve; the two pole shoes are respectively arranged on two sides of the ring-shaped permanent magnet in the axial direction of the magnetic conducting sleeve; each of the pole shoes is provided with a plurality of pole teeth on the side close to the magnetic conducting sleeve; the plurality of pole teeth are arranged in the plurality of grooves provided on the outer wall of the magnetic conducting sleeve one by one; the fourth gap exists between the pole teeth and the grooves;

[0019] a magnetic liquid, located between the pole teeth and the grooves, and filling the fourth gap.

[0020] In some embodiments of the present application, the magnetic fluid sealing assembly further comprises a cooling jacket shell; the cooling jacket shell is sleeved outside the pole shoe member and is fixedly connected with the sealing seat and the pole shoe member respectively; part of the outer wall of the cooling jacket shell is in close contact with the inner wall of the sealing seat in the circumferential direction, and the outer wall of the cooling jacket shell and the inner wall of the sealing seat jointly enclose a cooling gas flow space;

[0021] the sealing seat is provided with a second air inlet channel and a second air outlet channel; the second air inlet channel and the second air outlet channel are respectively in communication with the cooling gas flow space.

[0022] In some embodiments of the present application, the fixing assembly comprises a third lip-shaped sealing ring, a cover plate and a positioning block arranged on the first side of the pole shoe member;

[0023] the positioning block, the cover plate and the third lip-shaped sealing ring are sequentially arranged in the axial direction of the magnetic conducting sleeve towards the direction close to the pole shoe member;

[0024] the cover plate is sleeved outside the magnetic conducting sleeve and is partially located between the third lip-shaped sealing ring and the positioning block and partially located between the first side of the cooling jacket shell and the positioning block;

[0025] the third lip-shaped sealing ring is sleeved outside the magnetic conducting sleeve and presses the cover plate so that the cover plate is in close contact with the inner wall of the cooling jacket shell;

[0026] the positioning block is connected with the magnetic conducting sleeve so that the cover plate is in close contact with the first side of the cooling jacket shell;

[0027] the first side is the side away from the gas sealing assembly.

[0028] In some embodiments of the present application, the magnetically conductive sleeve is provided with a locking assembly at one end away from the gas sealing assembly; the locking assembly comprises a locking flange and a movable disc, both of which are sleeved on the outside of the magnetically conductive sleeve;

[0029] The locking assembly has a locked state and an unlocked state; when the locking assembly is in the locked state, the locking flange and the movable disc are close to each other to extrude the magnetically conductive sleeve to shrink inwardly; when the locking assembly is in the unlocked state, the locking flange and the movable disc are away from each other to release the magnetically conductive sleeve;

[0030] The sealing seat is provided with a balance pipe; the balance pipe extends from the outer wall of the sealing seat to the inner wall of the sealing seat, and one end of the balance pipe located at the inner wall of the sealing seat is covered by the split labyrinth seal member;

[0031] The split labyrinth seal member separates the balance pipe and the gas sealing channel.

[0032] Embodiments of the second aspect of the present application propose a screw compressor, comprising a housing, a rotating shaft and the sealing structure of any one of the embodiments of the first aspect;

[0033] The housing has an installation space inside; the housing is fixedly connected with the sealing seat;

[0034] The rotating shaft is arranged inside the installation space and penetrates through the magnetically conductive sleeve and is fixedly connected with the magnetically conductive sleeve.

[0035] Advantages:

[0036] The sealing structure of this embodiment includes a sealing seat, a fixing component, a magnetic bushing, a magnetic fluid sealing component, and a gas sealing component. The fixing component is connected to the sealing seat, and both the magnetic bushing and the magnetic fluid sealing component are connected to the fixing component, thereby achieving connection between the two and the sealing seat. The magnetic fluid sealing component is in close contact with the inner wall of the sealing seat and forms a magnetic fluid seal with the magnetic bushing, forming the first seal in the axial direction of the magnetic bushing. The gas sealing component is located on one side of the magnetic fluid sealing component in the axial direction of the magnetic bushing. The gas sealing component, the sealing seat, the magnetic bushing, the fixing component, and the magnetic fluid sealing component together enclose an annular gas flow space. The annular gas flow space is connected to the first inlet channel and the first outlet channel, respectively, forming a gas sealing channel. The sealing gas flowing in the gas sealing channel can form an annular gas seal, serving as the second seal in the axial direction of the magnetic bushing. The sealing structure of this embodiment provides two seals in the axial direction of the magnetic bushing, making the seal more reliable. Furthermore, the magnetic fluid seal has the advantages of good sealing effect and good corrosion resistance, which improves sealing reliability and extends seal life.

[0037] The screw compressor of this application embodiment includes a housing, a rotating shaft, and a sealing structure and sealing seat according to any embodiment of the first aspect. The housing is fixedly connected to the sealing seat; the rotating shaft is disposed inside the installation space of the housing, passes through the magnetic shaft sleeve, and is fixedly connected to the magnetic shaft sleeve to drive the magnetic shaft sleeve to rotate together. The sealing structure provides two seals in the axial direction of the magnetic shaft sleeve: a gas seal and a magnetic fluid seal, which makes the sealing more reliable. The magnetic fluid seal has the advantages of good sealing effect and good corrosion resistance, which improves the sealing reliability and helps to extend the seal life.

[0038] Of course, any product implementing this utility model does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0040] Figure 1 This is a schematic diagram of the sealing structure according to an embodiment of this application;

[0041] Figure 2 This is a flow path diagram of the sealing gas and cooling gas in the embodiments of this application;

[0042] Figure 3 for Figure 1 A magnified view of part B;

[0043] Figure 4 is a partial enlarged view of C of Figure 3

[0044] Figure 5 is a partial enlarged view of A of Figure 1

[0045] Figure 6 is a partial enlarged view of D of Figure 1

[0046] Reference signs: first gap G1;Second gap G2;Third gap G3;Fourth gap G4;Rotary shaft 20;Vortex tube refrigerator 30;Seal seat 100;First air inlet channel 110;First air outlet channel 120;Second air inlet channel 130;Second air outlet channel 140;Balance pipe 150;Connecting protrusion 160;Flange 170;Fixed assembly 200;Third lip-shaped sealing ring 210;Cover plate 220;End cover part 221;Extension part 222;Positioning block 230;Second fastener 240;First fastener 250;Magnetic conducting shaft sleeve 300;Groove 310;Second annular sealing tooth 320;Arc-shaped groove 330;Toothed structure 340;Magnetic fluid sealing assembly 400;Pole shoe member 410;Annular permanent magnet 411;Pole shoe 412;Pole tooth 4121;Magnetic liquid 413;Cooling clamp sleeve 420;Annular recess structure 421;Gas sealing assembly 500;Split labyrinth sealing member 510;Labyrinth sealing ring 511;First annular sealing tooth 5111;Labyrinth sealing mounting seat 512;First sealing member 520;First lip-shaped sealing ring 521;Sealing ring mounting seat 522;Mounting groove 5221;Second sealing member 530;Second lip-shaped sealing ring 531;First fixing member 532;Second fixing member 560;Locking assembly 600;Locking flange 610;Movable disc 620;Third fastener 630;First sealing ring 710;Second sealing ring 720;Third sealing ring 730;Fourth sealing ring 740;Fifth sealing ring 750;Sixth sealing ring 760. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art based on the present application belong to the scope of protection of the present application.

[0048] ​​​Screw compressors have the advantages of high reliability, simple operation and maintenance, and stable operation, and are widely used in many fields such as manufacturing and energy. The screw compressor in the related art usually adopts three forms of mechanical seals, namely single-end mechanical seal, double-end mechanical seal with flushing, and double-end dry gas mechanical seal. Due to the structural characteristics of the above three forms of mechanical seals, the sealing reliability is not high, and the sealing life is short. The three forms of mechanical seals are described below.

[0049] The single-end mechanical seal has a short service life and a high risk of leakage, and it is difficult to isolate the atmosphere end and the lubrication system from the process gas system. Once a failure occurs, it will cause the lubricating oil to enter the process gas system, or the process gas to enter the lubrication system or the process gas to leak, especially in the case of high-risk, toxic and harmful, and corrosive process gas, which is extremely dangerous.

[0050] The double-end mechanical seal with flushing has the risk of flushing liquid entering the process gas system; it is too difficult to select a sealing liquid that has no effect on the process system under some special working conditions, and liquids that are strongly corrosive and toxic, easily volatile, and easily crystallized are not suitable as sealing liquids; the selected sealing liquid enters the material system, which will pollute the process gas system or react with the process gas, greatly shortening the service life of this type of mechanical seal and causing leakage risk.

[0051] The double-end dry gas mechanical seal has high requirements for equipment manufacturing precision and equipment operation stability, and the manufacturing and maintenance cost of the mechanical seal is high. Because of the structural characteristics of the dry gas seal, inert gas or other gas needs to be introduced to make it function normally as a seal, and the pressure of the sealing gas used is generally higher than the working pressure of the compressor. The seal between the sealing gas and the screw cavity is mostly a lip seal, which has only one sealing part and has low reliability. After the lip seal fails, the leakage will increase dramatically, affecting the cleanliness of the process gas. At the same time, the seal cannot completely block the lubricating oil in the gear box from entering the material, and some process gases will react with some components in the lubricating oil under some use scenarios, which may affect the quality and cause temperature and pressure to be out of control. At the same time, some process gases in the use environment are corrosive and toxic, and if a leak occurs, it will not only cause personnel injury, but also cause damage to the equipment structure.

[0052] The above three mechanical seals are only suitable for clean, non-dangerous, and non-corrosive process gas working conditions. They are not suitable for some special, severe, highly corrosive, and dangerous working conditions. The reliability of the above three mechanical seals is not high, and the service life is short, which will cause the screw compressor to have frequent maintenance, leakage, corrosion, and lubrication system pollution during use. In order to solve the above technical problems, the embodiments of the present application provide a sealing structure and a screw compressor.

[0053] As Figure 1 and Figure 2 shown, Figure 1 is a structural schematic diagram of a sealing structure of an embodiment of the present application, Figure 2 is a flow path diagram of a sealing gas and a cooling gas in an embodiment of the present application, the embodiment of the first aspect of the present application proposes a sealing structure, which comprises a sealing seat 100, a fixing assembly 200, a magnetically conductive shaft sleeve 300, a magnetic fluid sealing assembly 400 and a gas sealing assembly 500. The sealing seat 100 has an accommodation space; the sealing seat 100 is provided with a first gas inlet channel 110 and a first gas outlet channel 120 which communicate with the accommodation space; the fixing assembly 200 is arranged in the accommodation space and connected with the sealing seat 100; the magnetically conductive shaft sleeve 300 is arranged in the accommodation space and connected with the fixing assembly 200; the magnetic fluid sealing assembly 400 is arranged between the outer wall of the magnetically conductive shaft sleeve 300 and the inner wall of the sealing seat 100 and connected with the fixing assembly 200; the magnetic fluid sealing assembly 400 is in close contact with the inner wall of the sealing seat 100 and forms a magnetic fluid seal with the magnetically conductive shaft sleeve 300; the gas sealing assembly 500 is arranged between the outer wall of the magnetically conductive shaft sleeve 300 and the inner wall of the sealing seat 100 and located on one side of the magnetic fluid sealing assembly 400 in the axial direction of the magnetically conductive shaft sleeve 300; the gas sealing assembly 500 is surrounded by the sealing seat 100, the magnetically conductive shaft sleeve 300, the fixing assembly 200 and the magnetic fluid sealing assembly 400 to form an annular gas flow space, which communicates with the first gas inlet channel 110 and the first gas outlet channel 120 respectively to form a gas sealing channel.

[0054] It can be understood that, as Figure 2 shown, the area through which the sealing gas flows is the area corresponding to the gas sealing channel, and the area remaining after the first gas inlet channel 110 and the first gas outlet channel 120 are removed corresponds to the annular gas flow space. After the screw compressor is installed, the magnetically conductive shaft sleeve 300 should be sleeved on the outside of the rotating shaft 20 and rotate with the rotating shaft 20 when the rotating shaft 20 rotates.

[0055] The sealing structure of the embodiment of the present application comprises a sealing seat 100, a fixing assembly 200, a magnetic conducting shaft sleeve 300, a magnetic fluid sealing assembly 400 and a gas sealing assembly 500. The fixing assembly 200 is connected with the sealing seat 100, and the magnetic conducting shaft sleeve 300 and the magnetic fluid sealing assembly 400 are both connected with the fixing assembly 200, so as to realize the connection of the two with the sealing seat 100; the magnetic fluid sealing assembly 400 is in close contact with the inner wall of the sealing seat 100 and forms a magnetic fluid seal with the magnetic conducting shaft sleeve 300, forming the first seal in the axial direction of the magnetic conducting shaft sleeve 300; the gas sealing assembly 500 is located on one side of the magnetic fluid sealing assembly 400 in the axial direction of the magnetic conducting shaft sleeve 300, and the gas sealing assembly 500, the sealing seat 100, the magnetic conducting shaft sleeve 300, the fixing assembly 200 and the magnetic fluid sealing assembly 400 jointly enclose an annular gas flow space, which is in communication with the first gas inlet channel 110 and the first gas outlet channel 120 respectively, forming a gas sealing channel. The flow of the sealing gas in the gas sealing channel can form an annular gas seal, serving as the second seal in the axial direction of the magnetic conducting shaft sleeve 300. The sealing structure of the embodiment of the present application has two seals in the axial direction of the magnetic conducting shaft sleeve 300, and the sealing is more reliable. Moreover, the magnetic fluid seal has the advantages of good sealing effect and good corrosion resistance, which helps to improve the sealing reliability and prolong the service life of the seal.

[0056] The side of the gas seal is the medium side (material side), and the other side is the atmospheric side. The medium leakage direction is as shown in Figure 1 Optionally, in the axial direction of the magnetic conducting shaft sleeve 300, the gas sealing assembly 500 can be arranged on the medium side, and the magnetic fluid sealing assembly 400 can be arranged on the atmospheric side. The sealing gas can be nitrogen or inert gas. In the use process, the sealing gas can be introduced into the gas sealing channel through the first gas inlet channel 110, and the sealing gas is discharged from the first gas outlet channel 120. The sealing gas fills the entire gas sealing channel, which can prevent the corrosive material inside the compressor from entering the magnetic fluid seal, thereby protecting the magnetic fluid seal. Moreover, nitrogen or inert gas will not corrode the magnetic fluid seal and is not easy to react with other substances, which helps to improve the reliability of the sealing structure.

[0057] In addition, a flowmeter can be arranged at the inlet of the first gas inlet channel 110 to detect the use amount of the sealing gas and determine whether the gas seal is failed. When the use amount of the sealing gas exceeds the preset range, it can be determined that the sealing gas leaks, and the shaft seal is failed. The sealing gas leakage mainly refers to the leakage of the sealing gas into the compressor, which will affect the quality of the material.

[0058] Specifically, as shown in Figure 1 and Figure 2As shown, the first gas inlet passage 110 and the first gas outlet passage 120 can be respectively arranged at two sides of the magnetic conducting sleeve 300 in the radial direction of the magnetic conducting sleeve 300; after the sealing gas enters through the first gas inlet passage 110, the sealing gas is divided into two parts and flows along the circumference of the magnetic conducting sleeve 300, fills the entire annular gas flow space, and then flows out through the first gas outlet passage 120, so that the gas flow path is smoother, and the path is annular, thereby ensuring the reliability of the sealing.

[0059] In some embodiments of the present application, as shown in Figure 1 and Figure 2 As shown, the gas sealing assembly 500 includes a split labyrinth sealing member 510, a first sealing member 520 and a second sealing member 530; the split labyrinth sealing member 510, the first sealing member 520 and the second sealing member 530 are sleeved outside the magnetic conducting sleeve 300 and are sequentially arranged in the axial direction of the magnetic conducting sleeve 300 towards the magnetic fluid sealing assembly 400, and together with the sealing seat 100, the magnetic conducting sleeve 300, the fixed assembly 200 and the magnetic fluid sealing assembly 400, the split labyrinth sealing member 510, the first sealing member 520 and the second sealing member 530 surround an annular gas flow space; the outlet of the first gas inlet passage 110 and the inlet of the first gas outlet passage 120 are both arranged towards the connection between the first sealing member 520 and the second sealing member 530, so as to respectively communicate the annular gas flow space with the first gas inlet passage 110 and the first gas outlet passage 120, thereby forming a gas sealing passage; the labyrinth seal is designed through a tortuous flow channel, so that the medium generates a throttling effect when passing through, thereby achieving the purpose of leakage prevention. The medium here can be sealing gas, and the structural features enable it to maintain good sealing performance in harsh environments such as high temperature, low temperature and high speed rotation, and have the advantages of good sealing effect and wide application range.

[0060] In some embodiments of the present application, as shown in Figure 2 to Figure 4 , Figure 3 is Figure 1 a local enlarged view of B of FIG. 8, Figure 4 is Figure 3A local enlarged schematic view at C of FIG. 10, the split labyrinth sealing member 510 is sleeved outside the magnetically conductive shaft sleeve 300, and an outer wall of the split labyrinth sealing member 510 is in close contact with and fixedly connected to the sealing seat 100. A side of the split labyrinth sealing member 510 close to the magnetically conductive shaft sleeve 300 is provided with a plurality of first annular sealing teeth 5111. The plurality of first annular sealing teeth 5111 are sequentially and spacedly arranged along an axial direction of the magnetically conductive shaft sleeve 300. The magnetically conductive shaft sleeve 300 is provided with a plurality of second annular sealing teeth 320 on a side close to the split labyrinth sealing member 510. The plurality of second annular sealing teeth 320 are sequentially and spacedly arranged along the axial direction of the magnetically conductive shaft sleeve 300 and are engaged with the plurality of first annular sealing teeth 5111. A first gap G1 exists between the first annular sealing teeth 5111 and the second annular sealing teeth 320. In the axial direction of the magnetically conductive shaft sleeve 300, an outlet of the first gas inlet channel 110 and an inlet of the first gas outlet channel 120 are located between the split labyrinth sealing member 510 and the magnetic fluid sealing assembly 400. The split labyrinth sealing member 510 in the embodiment of the present application cooperates with the second annular sealing teeth 320 of the magnetically conductive shaft sleeve 300 through the first annular sealing teeth 5111, so that the first gap G1 is smaller, the sealing performance is better, and the leakage of the sealing gas can be as low as 10-12 pa.m3 / s.

[0061] Optionally, as shown in Figure 3 and Figure 4 , the split labyrinth sealing member 510 can include a labyrinth sealing ring 511 sleeved outside the magnetically conductive shaft sleeve 300 and a labyrinth sealing mounting seat 512. The first annular sealing teeth 5111 are formed on the labyrinth sealing ring 511. The labyrinth sealing mounting seat 512 is located between the labyrinth sealing ring 511 and the sealing seat 100 to limit the displacement of the labyrinth sealing ring 511 in the radial direction of the magnetically conductive shaft sleeve 300. The inner wall of the sealing seat 100 can be formed with a connecting protrusion 160. Part of the structure of the labyrinth sealing ring 511 is located between the connecting protrusion 160 and the labyrinth sealing mounting seat 512. The first fastener 250 of the fixing assembly 200 is fixed by penetrating the connecting protrusion 160 and the labyrinth sealing mounting seat 512, so that the labyrinth sealing ring 511 is clamped by the connecting protrusion 160 and the labyrinth sealing mounting seat 512 to limit the displacement of the labyrinth sealing ring 511 in the axial direction of the magnetically conductive shaft sleeve 300.

[0062] In some embodiments of the present application, as shown in Figure 1 and Figure 3As shown, the first sealing member 520 is spaced apart from the split labyrinth sealing member 510, and the first sealing member 520 includes a sealing ring mounting seat 522 and a first lip-shaped sealing ring 521, which are sleeved on the outside of the magnetically conductive shaft sleeve 300; the sealing ring mounting seat 522 has a second gap G2 between the inner side and the magnetically conductive shaft sleeve 300, and the outer side is in close contact with the inner wall of the sealing seat 100, and the side close to the magnetic fluid sealing assembly 400 is provided with a mounting groove 5221; the first lip-shaped sealing ring 521 is arranged in the mounting groove 5221 and presses the sealing ring mounting seat 522, so that the sealing ring mounting seat 522 and the sealing seat 100 are relatively fixed and in contact with the second sealing member 530.

[0063] As shown in Figure 3 , the first lip-shaped sealing ring 521 plays a sealing and fixing role, so that the sealing ring mounting seat 522 and the sealing seat 100 are relatively fixed. By using the shape of the first lip-shaped sealing ring 521 and the sealing ring mounting seat 522, the shape of the annular gas flow space can be limited; the sealing ring mounting seat 522 and the first lip-shaped sealing ring 521 are spaced apart from the split labyrinth sealing member 510 and the magnetic fluid sealing assembly 400, so that the sealing ring mounting seat 522 has a gas space with the split labyrinth sealing member 510, and the first lip-shaped sealing ring 521 and the magnetic fluid sealing assembly 400 have a gas space; since the first lip-shaped sealing ring 521 is in clearance fit with the magnetically conductive shaft sleeve 300, the fit clearance can be 0.1mm-0.5mm, and the first lip-shaped sealing ring 521 will also be worn out during the rotation of the magnetically conductive shaft sleeve 300, therefore, when the magnetically conductive shaft sleeve 300 is rotated under the driving of the rotating shaft 20, there is a gap (not shown in the figure) between the first lip-shaped sealing ring 521 and the outer wall of the magnetically conductive shaft sleeve 300, so that the two gas spaces can be communicated through the gap and the second gap G2, and the sealing gas can fill the gas space and flow to the split labyrinth sealing member 510.

[0064] In some embodiments of the present application, as Figure 1 and Figure 3As shown, the second sealing member 530 includes a second lip seal 531 and a first fixing member 532; the second lip seal 531 is sleeved on the outside of the magnetic conducting sleeve 300, and the outside thereof is in close contact with the magnetic fluid sealing assembly 400; the first fixing member 532 is arranged between the first lip seal 521 and the second lip seal 531, and abuts against the two respectively, so that there is a third gap G3 between the first lip seal 521 and the second lip seal 531, and the third gap G3 and the second gap G2 are communicated; the first fixing member 532 is provided with at least two through hole structures (not shown in the figure), wherein at least one of the through hole structures is arranged towards the outlet of the first air inlet channel 110, and communicates the first air inlet channel 110 and the third gap G3, and at least one of the through hole structures is arranged towards the inlet of the first air outlet channel 120, and communicates the third gap G3 and the first air outlet channel 120. By arranging the second lip seal 531 and the first fixing member 532, the size of the annular gas flow space can be controlled, so that the amount of sealing gas can be controlled; the sealing gas can flow from the gap between the second lip seal 531 and the magnetic conducting sleeve 300 to the pole shoe member 410, since the gap is very small, it has the effect of controlling the pressure and flow rate of the sealing gas, which can reduce the impact and pollution of the gas or possible material on the pole shoe member 410, and has the effect of protecting the pole shoe member 410; the sealing gas flow path is as follows: Figure 4 .

[0065] In some embodiments of the present application, as shown in Figure 3 , the gas sealing assembly 500 can further include a second fixing member 560, which is arranged between the pole shoe member 410 and the second lip seal 531 to position the second lip seal 531 and prevent displacement of the second lip seal 531.

[0066] In some embodiments of the present application, as shown in Figure 1 , Figure 2 , Figure 5 , Figure 5 , Figure 1A local enlarged view of A in FIG. 4 shows that the magnetic fluid sealing assembly 400 comprises a pole shoe member 410; the pole shoe member 410 is fixedly connected with the sealing seat 100 and comprises an annular permanent magnet 411 and two pole shoes 412; the annular permanent magnet 411 is sleeved outside the magnetically conductive sleeve 300; the two pole shoes 412 are sleeved outside the magnetically conductive sleeve 300; the two pole shoes 412 are respectively arranged on two sides of the annular permanent magnet 411 in the axial direction of the magnetically conductive sleeve 300; each pole shoe 412 is provided with a plurality of pole teeth 4121 on the side close to the magnetically conductive sleeve 300; the plurality of pole teeth 4121 are arranged in the plurality of grooves 310 provided on the outer wall of the magnetically conductive sleeve 300 one by one; the fourth gap G4 exists between the pole teeth 4121 and the grooves 310; the magnetic liquid 413 is located between the pole teeth 4121 and the grooves 310 and fills the fourth gap G4. The magnetic field generated by the annular permanent magnet 411 causes the magnetic liquid 413 to be affected by the rotating magnetic field loop formed by the pole shoe 412 and the magnetically conductive sleeve 300, to be firmly adsorbed between the tip (pole tooth 4121) of the pole shoe 412 and the magnetically conductive sleeve 300, and to fill the fourth gap G4, thereby forming a plurality of sealing rings similar to O-rings arranged in sequence in the axial direction of the magnetically conductive sleeve 300, so as to completely isolate the material gas from the external environment (atmosphere side); and the magnetic liquid 413 has a certain acid and alkali resistance, which greatly improves the service life and recycling rate of this type of sealing. The natural loss period of the magnetic fluid sealing is longer than the theoretical use period of the ordinary lip seal, which is beneficial to prolong the service life of the sealing structure, and compared with a plurality of lip seals connected in series, the magnetic fluid sealing has a smaller size, the overall size of the equipment is shorter, the size of the sealing seat 100 and the magnetically conductive sleeve 300 is shorter, which saves space and reduces cost.

[0067] In some embodiments of the present application, as shown in Figure 1 and Figure 2 , the magnetic fluid sealing assembly 400 further comprises a cooling jacket shell 420; the cooling jacket shell 420 is sleeved outside the pole shoe member 410 and is fixedly connected with the sealing seat 100 and the pole shoe member 410 respectively; part of the outer wall of the cooling jacket shell 420 is in close contact with the inner wall of the sealing seat 100 in the circumferential direction, and the outer wall of the cooling jacket shell 420 and the inner wall of the sealing seat 100 jointly enclose a cooling gas flow space; the sealing seat 100 is provided with a second gas inlet channel 130 and a second gas outlet channel 140; the second gas inlet channel 130 and the second gas outlet channel 140 are respectively in communication with the cooling gas flow space. As can be understood, as shown in Figure 2 , the area through which the cooling gas flows corresponds to the cooling gas flow space after removing the second gas inlet channel 130 and the second gas outlet channel 140.

[0068] When the rotating shaft 20 rotates, the magnetic guide sleeve 300 rotates, and the magnetic guide sleeve 300 rotates relative to the pole shoe component 410, so that the magnetic liquid 413 (magnetic fluid) body generates heat, and the cooling gas is injected into the cooling gas flow space to complete heat exchange and cool the magnetic liquid 413, thereby ensuring the reliability of the sealing structure and prolonging the service life.

[0069] Optionally, the inner wall of the cooling jacket shell 420 can be provided with a clamping groove (not shown in the figure), and the pole shoe component 410 can be directly clamped in the clamping groove to realize the fixation between the two. The second gas inlet channel 130 and the second gas outlet channel 140 can be arranged on the same side of the magnetic guide sleeve 300 in the radial direction of the magnetic guide sleeve 300 and are arranged at intervals in the axial direction of the magnetic guide sleeve 300; the outer wall of the cooling jacket shell 420 can be inwardly recessed to form two annular recessed structures 421, and the two annular recessed structures 421 are respectively connected with the second gas inlet channel 130 and the second gas outlet channel 140, and the sides of the two annular recessed structures 421 away from the second gas inlet channel 130 and the second gas outlet channel 140 are communicated with each other, so that the cooling gas can flow into one annular recessed structure 421 through the inlet of the second gas inlet channel 130, then flow into the other annular recessed structure 421, and finally flow out through the second gas outlet channel 140; the above arrangement forms two annular channels, and the cooling efficiency is higher.

[0070] Optionally, the cooling gas can be nitrogen; a vortex tube refrigerator 30 can be provided, and vortex tube refrigeration is a method of separating cold gas flow and hot gas flow from high-speed gas (compressed gas) by means of vortex tube, and using the cold gas flow to refrigerate. The vortex tube refrigerator 30 is used to supply the cooling gas.

[0071] In some embodiments of the present application, as Figure 1As shown, the fixing assembly 200 includes a third lip-shaped sealing ring 210, a cover plate 220 and a positioning block 230 arranged on the first side of the pole piece member 410; the positioning block 230, the cover plate 220 and the third lip-shaped sealing ring 210 are sequentially arranged in the direction of the axial direction of the magnetic conducting sleeve 300 and close to the pole piece member 410; the cover plate 220 is sleeved on the outer side of the magnetic conducting sleeve 300 and partially located between the third lip-shaped sealing ring 210 and the positioning block 230 and partially located between the first side of the cooling jacket shell 420 and the positioning block 230; the third lip-shaped sealing ring 210 is sleeved on the outer side of the magnetic conducting sleeve 300 and presses the cover plate 220, so that the cover plate 220 is tightly attached to the inner wall of the cooling jacket shell 420; the positioning block 230 is clamped with the magnetic conducting sleeve 300, so that the cover plate 220 is tightly attached to the first side of the cooling jacket shell 420; the first side is the side away from the gas sealing assembly 500. The fixing in the radial direction of the magnetic conducting sleeve 300 is realized through the third lip-shaped sealing ring 210 and the cover plate 220, and the fixing of the magnetic fluid sealing assembly 400 in the axial direction of the magnetic conducting sleeve 300 is realized through the positioning block 230 and the cover plate 220, and the fixing mode is simple and reliable.

[0072] Specifically, the cover plate 220 includes a connecting arranged end cover part 221 and an extension part 222; the end cover part 221 is sleeved on the outer side of the magnetic conducting sleeve 300 and located between the cooling jacket shell 420 and the first side of the third lip-shaped sealing ring 210; the extension part 222 is sleeved on the outer side of the magnetic conducting sleeve 300 and extends from the end cover part 221 to the pole piece member 410 and located between the cooling jacket shell 420 and the third lip-shaped sealing ring 210 in the radial direction of the magnetic conducting sleeve 300; the third lip-shaped sealing ring 210 tightly presses the extension part 222 to the inner wall of the cooling jacket shell 420; the positioning block 230 tightly presses the end cover part 221 to the cooling jacket shell 420.

[0073] The lip-shaped sealing ring is made of rubber material and has good sealing performance, can play a good sealing effect in high temperature, high pressure, high speed and other harsh environments, and effectively protect mechanical equipment; the lip-shaped sealing ring has good pressure resistance, wide applicable pressure range, can maintain good sealing performance within a certain pressure and temperature range, has the advantages of convenient installation, good sealing performance and wide application range.

[0074] In some embodiments of the present application, as shown in Figure 1 The fixing assembly 200 can further include a second fastener 240, and the cooling jacket shell 420 is fixedly connected with the sealing seat 100 through the second fastener 240 to improve the connection reliability.

[0075] In some embodiments of the present application, as shown in Figure 1As shown, the end of the magnetic conducting sleeve 300 away from the gas sealing assembly 500 is provided with a locking assembly 600; the locking assembly 600 includes a locking flange 610 and a movable disc 620, which are sleeved on the outside of the magnetic conducting sleeve 300; the locking assembly 600 has a locking state and an unlocking state; when the locking assembly 600 is in the locking state, the locking flange 610 and the movable disc 620 are close to each other to extrude the magnetic conducting sleeve 300 to shrink inward; when the locking assembly 600 is in the unlocking state, the locking flange 610 and the movable disc 620 are away from each other to release the magnetic conducting sleeve 300. Figure 1 When the locking assembly 600 is in the unlocking state, the movable disc 620 is at the arc-shaped groove 330 of the outer wall of the magnetic conducting sleeve 300; during the switching process of the locking assembly 600 from the unlocking state to the locking state, the movable disc 620 moves rightward and the locking flange 610 moves leftward, thereby restraining the magnetic conducting sleeve 300, making the magnetic conducting sleeve 300 shrink and tightly hold the rotating shaft 20; the arc-shaped groove 330 facilitates the sliding of the movable disc 620.

[0076] The locking flange 610 and the movable disc 620 can be fixedly connected through a third fastener 630; in this way, the switching between the locking state and the unlocking state of the locking assembly 600 can be realized by tightening or loosening the third fastener 630, which is simple to operate.

[0077] Optionally, as shown in Figure 6 , Figure 6 , Figure 1 is a local enlarged view of D, the inner wall of the magnetic conducting sleeve 300 can be provided with a plurality of tooth-shaped structures 340 for contacting the rotating shaft 20, thereby increasing the friction between the magnetic conducting sleeve 300 and the rotating shaft 20 and facilitating the fixation therebetween.

[0078] In some embodiments of the present application, as shown in Figure 1 , the sealing seat 100 can be provided with a balance pipe 150; the balance pipe 150 extends from the outer wall of the sealing seat 100 to the inner wall of the sealing seat 100, and one end thereof located on the inner wall of the sealing seat 100 is covered by the split labyrinth sealing member 510; the split labyrinth sealing member 510 separates the balance pipe 150 and the gas sealing channel. In this way, by controlling the pressure in the balance pipe 150, the pressure on both sides of the split labyrinth sealing member 510 can be balanced to prevent the pressure from being too high or too low, thereby affecting the amount of sealing gas used. The position of the sealing structure is divided into high-pressure side sealing and low-pressure side sealing, the high-pressure end refers to the end of the unit cavity (medium end), and the low-pressure end refers to the atmospheric end; the high-pressure side sealing refers to the sealing close to the gas outlet of the unit, and the low-pressure side sealing refers to the sealing close to the gas inlet of the unit. Figure 1The diagram shows the high-pressure side seal; the balance pipe 150 helps balance the axial force by introducing the medium gas from the high-pressure end to the low-pressure end, reducing the impact of axial thrust on the compressor rotor and improving stability. The seal seat 100 may also be equipped with a flange 170 for connection.

[0079] Specifically, nitrogen can be used as the sealing gas. The balance pipe 150 can be connected to the unit's working chamber (not shown in the figure) through the unit's outlet pipe (not shown in the figure). The gas pressure in the balance pipe 150 is the same as or slightly lower than that in the working chamber. To ensure that the material medium does not spread to the low-pressure end of the mechanical seal, the pressure of the introduced nitrogen must be higher than the working pressure of the material. Therefore, the nitrogen (sealing gas) introduced to prevent corrosive material medium from entering the pole shoe component 410 and losing the magnetohydrodynamic seal must have a pressure higher than the medium side pressure, that is, the nitrogen introduction pressure must be higher than the pressure in the unit's working chamber. Since the pressure difference between the nitrogen and the medium side of the high-pressure mechanical seal is smaller, an axial force will be generated. The high-pressure gas connected to the compressor outlet pipe through the balance pipe 150 can reduce the pressure difference, thereby reducing the axial force and improving stability. Therefore, the low-pressure side seal does not need to be equipped with a balance pipe 150.

[0080] like Figure 1 As shown, in order to achieve a better sealing effect, a first sealing ring 710 can be set between the labyrinth sealing ring 511 and the inner wall of the sealing seat 100. The first sealing ring 710 is located on the side of the balance tube 150 away from the magnetic fluid sealing assembly 400. With this setting, a small amount of sealing gas will enter the balance tube 150 through the tiny gap between the labyrinth sealing mounting seat 512 and the sealing seat 100, achieving a better balance effect.

[0081] A second sealing ring 720 may be provided between the outer side of the sealing ring mounting seat 522 and the inner wall of the sealing seat 100; a third sealing ring 730 and a fourth sealing ring 740 may be provided between the outer wall of the cooling jacket housing 420 and the inner wall of the sealing seat 100, the third sealing ring 730 and the fourth sealing ring 740 being respectively disposed on both sides of the two annular recessed structures 421 in the axial direction of the magnetic guide sleeve 300; a fifth sealing ring 750 and a sixth sealing ring 760 may be provided between the inner wall of the magnetic guide sleeve 300 and the rotating shaft 20, the fifth sealing ring 750 and the sixth sealing ring 760 being spaced apart. The first sealing ring 710 to the sixth sealing ring 760 may be O-rings.

[0082] The sealing structure in the embodiment of the application is sealed by the first gas inlet channel 110, the annular gas flow space and the split labyrinth sealing member 510, and then the first gas outlet channel 120 returns to the external nitrogen system, thereby forming a gas seal. When the medium flows in the leakage direction, it first passes through the labyrinth seal, then passes through the gas seal, and then passes through the magnetic fluid seal, thereby achieving triple sealing, and the sealing reliability is higher. The cooling gas is introduced into the cooling gas flow space to exchange heat with the magnetic liquid 413, thereby cooling the magnetic liquid 413, reducing the influence of friction heat, and making the sealing performance more reliable, thereby prolonging the service life of the mechanical seal, reducing the maintenance frequency and the maintenance cost in the later period; the labyrinth seal is arranged to make the sealing gas leakage extremely small, and there is no risk of oil leakage into the material system before the magnetic fluid seal completely fails; there is no risk of contamination of the system by the sealing liquid; the magnetic fluid seal has a certain corrosion resistance and can be applied to some special, harsh, highly corrosive and dangerous working conditions. Before starting, it is first confirmed that the cooling gas and the sealing gas (nitrogen) pressure are normal, and the nitrogen pressure needs to be higher than 0.6 MPa at the first start to prevent the material from entering the system due to improper installation; after normal starting, the inlet temperature is controlled to be above-20 DEG C to avoid failure of the first sealing ring 710 to the sixth sealing ring 760 in a low-temperature environment; after normal operation, whether the nitrogen leaks into the system is determined by monitoring the nitrogen flux; a gas leakage detector can also be arranged to detect whether the material gas leaks, thereby determining whether the seal fails.

[0083] The second aspect of the application provides a screw compressor, which comprises a shell (not shown in the figure), a rotating shaft 20 and the sealing structure of any one of the embodiments of the first aspect; the shell has an installation space inside; the shell is fixedly connected with the sealing seat 100; the rotating shaft 20 is arranged inside the installation space and penetrates through the magnetic guide sleeve 300 and is fixedly connected with the magnetic guide sleeve 300.

[0084] The screw compressor of the embodiment of the application comprises a shell, a rotating shaft 20 and the sealing structure of any one of the embodiments of the first aspect. The shell is fixedly connected with the sealing seat 100; the rotating shaft 20 is arranged inside the installation space of the shell and penetrates through the magnetic guide sleeve 300 and is fixedly connected with the magnetic guide sleeve 300 to drive the magnetic guide sleeve 300 to rotate together. The sealing structure is provided with two seals, i.e., a gas seal and a magnetic fluid seal, in the axial direction of the magnetic guide sleeve 300, the sealing is more reliable, and the magnetic fluid seal has the advantages of good sealing effect and good corrosion resistance, thereby improving the sealing reliability and prolonging the service life of the seal.

[0085] Optionally, the number of the rotating shafts 20 can be two, and the number of the sealing structures can be four, which can be arranged at the two ends of the two rotating shafts 20.

[0086] The above merely describes preferred embodiments of the present application, and is not intended to limit the scope of protection of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A sealing structure, characterized in that, include: A sealing seat (100) has a receiving space; the sealing seat (100) is provided with a first air inlet channel (110) and a first air outlet channel (120) communicating with the receiving space; A fixing component (200) is disposed within the receiving space and connected to the sealing seat (100); A magnetic bushing (300) is disposed within the receiving space and connected to the fixing assembly (200); A magnetic fluid sealing assembly (400) is disposed between the outer wall of the magnetic guide sleeve (300) and the inner wall of the sealing seat (100), and is connected to the fixing assembly (200); the magnetic fluid sealing assembly (400) is in close contact with the inner wall of the sealing seat (100) and forms a magnetic fluid seal with the magnetic guide sleeve (300); A gas sealing assembly (500) is disposed between the outer wall of the magnetic bushing (300) and the inner wall of the sealing seat (100), located on one side of the magnetic fluid sealing assembly (400) in the axial direction of the magnetic bushing (300); the gas sealing assembly (500), the sealing seat (100), the magnetic bushing (300), the fixing assembly (200), and the magnetic fluid sealing assembly (400) together enclose an annular gas flow space, which is connected to the first inlet channel (110) and the first outlet channel (120) respectively, forming a gas sealing channel.

2. The sealing structure according to claim 1, characterized in that, The gas sealing assembly (500) includes: a split labyrinth sealing member (510), a first sealing member (520), and a second sealing member (530); The split labyrinth sealing member (510), the first sealing member (520) and the second sealing member (530) are sleeved on the outside of the magnetic bushing (300) and arranged sequentially along the axial direction of the magnetic bushing (300) towards the magnetic fluid sealing assembly (400), and together with the sealing seat (100), the magnetic bushing (300), the fixing assembly (200) and the magnetic fluid sealing assembly (400), they form an annular gas flow space. The outlet of the first air intake channel (110) and the inlet of the first air outlet channel (120) are both arranged toward the connection between the first sealing member (520) and the second sealing member (530) so that the annular gas flow space is connected to the first air intake channel (110) and the first air outlet channel (120) respectively.

3. The sealing structure according to claim 2, characterized in that, The split labyrinth sealing member (510) has its outer wall in close contact with and fixedly connected to the sealing seat (100). It has a plurality of first annular sealing teeth (5111) on the side near the magnetic bushing (300). The plurality of first annular sealing teeth (5111) are arranged sequentially at intervals along the axial direction of the magnetic bushing (300). The magnetic bushing (300) has a plurality of second annular sealing teeth (320) on one side near the split labyrinth sealing member (510); the plurality of second annular sealing teeth (320) are arranged sequentially at intervals along the axial direction of the magnetic bushing (300) and engage with the plurality of first annular sealing teeth (5111); there is a first gap (G1) between the first annular sealing teeth (5111) and the second annular sealing teeth (320).

4. The sealing structure according to claim 3, characterized in that, The first sealing member (520) and the split labyrinth sealing member (510) are spaced apart, and include: a sealing ring mounting seat (522) and a first lip sealing ring (521), which are sleeved on the outside of the magnetic shaft sleeve (300); The sealing ring mounting seat (522) has a second gap (G2) between its inner side and the magnetic bushing (300), and its outer side is in close contact with the inner wall of the sealing seat (100). The side of the sealing ring mounting seat (522) near the magnetic fluid sealing assembly (400) is provided with a mounting groove (5221). The first lip seal (521) is disposed in the mounting groove (5221) and presses the seal ring mounting seat (522) so that the seal ring mounting seat (522) and the sealing seat (100) are relatively fixed and are in contact with the second sealing member (530).

5. The sealing structure according to claim 4, characterized in that, The second sealing member (530) includes: The second lip seal (531) is fitted on the outside of the magnetic shaft sleeve (300); its outer side is in close contact with the magnetic fluid sealing assembly (400); A first fixing member (532) is disposed between the first lip seal (521) and the second lip seal (531) and abuts against them respectively, so that a third gap (G3) exists between the first lip seal (521) and the second lip seal (531), and the third gap (G3) and the second gap (G2) are connected; the first fixing member (532) is provided with at least two through hole structures, wherein at least one of the through hole structures is disposed facing the outlet of the first air intake channel (110) and connecting the first air intake channel (110) and the third gap (G3), and at least one of the through hole structures is disposed facing the inlet of the first air outlet channel (120) and connecting the third gap (G3) and the first air outlet channel (120).

6. The sealing structure according to any one of claims 1 to 5, characterized in that, The magnetohydrodynamic sealing assembly (400) includes a pole shoe member (410); the pole shoe member (410) is fixedly connected to the sealing seat (100), and includes: A ring-shaped permanent magnet (411) is sleeved on the outside of the magnetic guide sleeve (300); Two pole shoes (412) are sleeved on the outside of the magnetic bushing (300); the two pole shoes (412) are respectively disposed on both sides of the annular permanent magnet (411) in the axial direction of the magnetic bushing (300); each pole shoe (412) has a plurality of pole teeth (4121) on the side near the magnetic bushing (300); the plurality of pole teeth (4121) are disposed one-to-one in a plurality of grooves (310) provided on the outer wall of the magnetic bushing (300); a fourth gap (G4) exists between the pole teeth (4121) and the grooves (310); Magnetic fluid (413) is located between the pole teeth (4121) and the groove (310) and fills the fourth gap (G4).

7. The sealing structure according to claim 6, characterized in that, The magnetohydrodynamic sealing assembly (400) further includes: a cooling jacket housing (420); the cooling jacket housing (420) is sleeved on the outside of the pole shoe member (410) and is fixedly connected to the sealing seat (100) and the pole shoe member (410) respectively; a portion of the outer wall of the cooling jacket housing (420) is in close contact with the inner wall of the sealing seat (100) in the circumferential direction, and the outer wall of the cooling jacket housing (420) and the inner wall of the sealing seat (100) together enclose a cooling gas flow space; The sealing seat (100) is provided with a second air inlet channel (130) and a second air outlet channel (140); the second air inlet channel (130) and the second air outlet channel (140) are respectively connected to the cooling gas flow space.

8. The sealing structure according to claim 7, characterized in that, The fixing assembly (200) includes: a third lip seal (210), a cover plate (220), and a positioning block (230) disposed on the first side of the pole shoe component (410); The positioning block (230), the cover plate (220), and the third lip seal ring (210) are arranged sequentially in the axial direction of the magnetic bushing (300) towards the pole shoe component (410); The cover plate (220) is sleeved on the outside of the magnetic bushing (300) and is partially located between the third lip seal ring (210) and the positioning block (230), and partially located between the first side of the cooling jacket housing (420) and the positioning block (230). The third lip seal (210) is fitted on the outside of the magnetic bushing (300) and presses the cover plate (220) so that the cover plate (220) fits tightly against the inner wall of the cooling jacket housing (420); The positioning block (230) engages with the magnetic bushing (300) so that the cover plate (220) fits tightly against the first side of the cooling jacket housing (420); The first side is the side away from the gas sealing assembly (500).

9. The sealing structure according to claim 2, characterized in that, The magnetic bushing (300) has a locking assembly (600) at one end away from the gas sealing assembly (500); the locking assembly (600) includes a locking flange (610) and a movable disc (620), which are sleeved on the outside of the magnetic bushing (300); The locking assembly (600) has a locked state and an unlocked state; when the locking assembly (600) is in the locked state, the locking flange (610) and the movable disc (620) move closer to each other to compress the magnetic bushing (300) inward; when the locking assembly (600) is in the unlocked state, the locking flange (610) and the movable disc (620) move further apart to release the magnetic bushing (300); The sealing seat (100) is provided with a balance tube (150); the balance tube (150) extends from the outer wall of the sealing seat (100) to the inner wall of the sealing seat (100), and one end of it located on the inner wall of the sealing seat (100) is covered by the split labyrinth sealing member (510). The split labyrinth sealing member (510) separates the balance tube (150) from the gas sealing channel.

10. A screw compressor, characterized in that, include: The housing, the rotating shaft (20), and the sealing structure according to any one of claims 1-9; The housing has an internal installation space; the housing is fixedly connected to the sealing seat (100); The rotating shaft (20) is disposed inside the installation space and passes through the magnetic bushing (300), and is fixedly connected to the magnetic bushing (300).

Images