External shaft seal of ventilator

Abstract

The utility model relates to the technical field of ventilator equipment, in particular to an external shaft seal of a ventilator, which comprises a casing, a main shaft, a bearing box body and a sealing component, the casing, the sealing component and the bearing box body are sequentially lapped on the outer surface of the main shaft, two ends of the sealing component are respectively attached to one side of the casing and the bearing box body, and the sealing component is arranged on the outer surface of the main shaft. The sealing assembly comprises a corrugated pipe, two tetrafluoroethylene pads and an interlayer, the two ends of the corrugated pipe are fixedly connected with flange ends, and one sides of the two tetrafluoroethylene pads are in lap joint with one sides of the corresponding flange ends. According to the utility model, the assembly of the aluminum maze and the main shaft is in clearance fit of 0.2-0.3 mm, the corrugated pipe can compensate the deformation of the casing, the mounting clearance of the aluminum maze and the main shaft can be ensured for a long time, the gas leakage is effectively prevented, the leakage prevention is enhanced, the maze clearance can be ensured, and the outward leakage effect is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of ventilator equipment, in particular to an external shaft seal of a ventilator. Background Art

[0002] In the application of fans, high-temperature fans represented by tail gas pressurization and flue gas recirculation have the situation that the maze seal at the shaft seal rubs against the main shaft due to the thermal deformation of the fan casing (the maze seal mainly prevents gas leakage by forming gas films layer by layer with a small distance from the shaft).

[0003] Some existing high-temperature shaft seals generally adopt aluminum maze plus packing seal. Due to the high temperature of the conveyed gas, the thermal expansion of the casing steel easily changes the clearance between the maze at the shaft seal and the main shaft or even causes friction. As a result, the vibration or thermal deformation of the fan casing causes the displacement of the casing, which easily leads to the damage of the main shaft seal, the reduction of strength or even fracture, causing irreversible losses to production safety. Content of the Utility Model

[0004] In order to avoid the displacement of the casing caused by the vibration or thermal deformation of the fan casing, the utility model provides an external shaft seal of a ventilator.

[0005] The external shaft seal of a ventilator provided by the utility model adopts the following technical scheme:

[0006] An external shaft seal of a ventilator includes a casing, a main shaft, a bearing box body and a sealing assembly. The casing, the sealing assembly and the bearing box body are sequentially lapped on the outer surface of the main shaft. The two ends of the sealing assembly are respectively in contact with one side of the casing and the bearing box body. The sealing assembly includes a corrugated pipe, two polytetrafluoroethylene gaskets and a spacer layer. Flange ends are fixedly connected to both ends of the corrugated pipe. One side of each of the two polytetrafluoroethylene gaskets is lapped on one side of the corresponding flange end. The two polytetrafluoroethylene gaskets are symmetrically distributed on both sides of the corrugated pipe.

[0007] By adopting the above technical scheme, the sealing assembly is external. The corrugated pipe of the sealing device is in clearance fit with the main shaft by 0.2 - 0.3 mm, and the corrugated pipe can self-compensate for the deformation of the casing.

[0008] Preferably, a gland is lapped on one side of the bearing box body close to the corrugated pipe, and the inside of the gland is lapped on the outer surface of the main shaft.

[0009] By adopting the above technical scheme, the direct contact between the dust-proof graphite gasket and the gland is avoided through the pressing plate.

[0010] Preferably, the spacer layer includes an aluminum maze, a dust-proof graphite gasket and a pressing plate, and the aluminum maze, the dust-proof graphite gasket and the pressing plate are sequentially lapped on the outer surface of the main shaft.

[0011] By adopting the above technical solution, multi-layer leak prevention measures are taken to enhance the leak prevention effect, so that the maze gap of the aluminum maze can be guaranteed, effectively reducing external leakage.

[0012] Preferably, the other side of one of the polytetrafluoroethylene gaskets overlaps the outer surface of the aluminum maze, and the other side of the other polytetrafluoroethylene gasket overlaps the outer surface of the casing.

[0013] By adopting the above technical solution, the polytetrafluoroethylene gasket is used as an intermediate cushion layer to fill the outer surfaces of the flange end and the casing, avoiding gaps caused by uneven surfaces between the flange end and the casing and preventing medium leakage.

[0014] Preferably, a number of through holes 1 are provided on the outer surfaces of one of the flange ends, one of the polytetrafluoroethylene gaskets, the aluminum maze, the dust-proof graphite gasket, the gland and the pressing plate, which are arranged in a circumferential array with the central axis of the main shaft as the center. Every six corresponding through holes 1 form a group, and a long bolt is fixedly connected inside each group of through holes 1. Two nuts 1 are fixedly connected to the outer surface of each long bolt. One part of the nuts 1 is clamped on one side of the pressing plate, and the other part of the nuts 1 is clamped on one side of the gland. One end of the long bolt is threadedly connected to the inside of the bearing box body, and the other end of the long bolt is clamped on one side of the corresponding flange end.

[0015] By adopting the above technical solution, the flange end of the bellows is connected to the bearing box body through bolts, and then one part of the nuts 1 is used to lock the polytetrafluoroethylene gasket, the aluminum maze, the dust-proof graphite gasket and the pressing plate, and the other part of the nuts 1 is used to lock the bearing box body and the gland.

[0016] Preferably, a number of through holes 2 are provided on the outer surface of the other flange end and one side of the casing, which are arranged in a circumferential array with the central axis of the main shaft as the center. Every two corresponding through holes 2 form a group, and a short bolt is inserted into each group of through holes 2. A nut 2 is fixedly connected to the outer surface of each short bolt, and one side of each nut 2 is clamped on one side of the casing.

[0017] By adopting the above technical solution, the flange end of the bellows is connected to the casing through short bolts, thereby connecting the bellows and the casing. When the casing of the fan vibrates or is deformed by heat, the bellows compensates for the displacement of the casing caused thereby.

[0018] In summary, the utility model has the following beneficial technical effects:

[0019] 1. The device is provided with a sealing assembly, which includes a bellows, a polytetrafluoroethylene gasket, an aluminum labyrinth, a dust-proof graphite gasket, and a pressing plate. The assembly of the aluminum labyrinth and the main shaft has a clearance fit of 0.2 - 0.3 mm. The bellows can self-compensate for the deformation of the machine housing. The installation clearance between the aluminum labyrinth and the main shaft can be guaranteed for a long time, effectively preventing gas leakage, enhancing the anti-leakage performance, ensuring the labyrinth clearance, and effectively reducing external leakage.

[0020] 2. The sealing assembly of the device is externally placed. One flange end of the bellows is fixed to the machine housing of the fan with short bolts on the fan housing, and a polytetrafluoroethylene gasket is added in the middle. The other flange end of the bellows is sequentially connected with a polytetrafluoroethylene gasket, an aluminum labyrinth, a dust-proof graphite gasket, and a pressing plate. All of them are connected to the bearing housing with long bolts through the gland and the bearing housing body, making good use of the bearing housing without the need for additional welded mounting brackets, which is beneficial to reducing the cost of the fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of an external shaft seal of a ventilator according to the present utility model;

[0022] Figure 2 is a schematic structural diagram of the sealing assembly in the external shaft seal of a ventilator according to the present utility model;

[0023] Figure 3 is Figure 2 a partially enlarged schematic diagram of the local structure in;

[0024] Figure 4 is Figure 2 a partially enlarged schematic diagram of the local structure in;

[0025] Figure 5 is a schematic structural diagram of the shaft seal of the fan in the background art.

[0026] Description of the reference numerals:

[0027] 1. Machine housing; 2. Flange end; 3. Polytetrafluoroethylene gasket; 4. Aluminum labyrinth; 5. Dust-proof graphite gasket; 6. Gland; 7. Bellows; 8. Bearing housing body; 9. Long bolt; 10. Main shaft; 11. Pressing plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The following further describes the present utility model in detail with reference to the attached Figures 1-5 drawings.

[0029] Referring to Figure 5 , due to the high gas temperature of the high-temperature fan, the housing of the fan housing 1 generates thermal deformation. Generally, the clearance between the labyrinth and the main shaft 10 is increased. However, after the housing is deformed, the clearance is uneven and the flue gas leaks seriously. When the deformation is too large, wear will also occur, reducing its service life.

[0030] An embodiment of the utility model discloses an external shaft seal for a ventilator.

[0031] Referring to Figure 1 and Figure 2 , it includes a casing 1, a main shaft 10, a bearing box body 8 and a sealing assembly. The casing 1, the sealing assembly and the bearing box body 8 are successively lapped on the outer surface of the main shaft 10. Both ends of the sealing assembly are respectively in contact with one side of the casing 1 and the bearing box body 8. The sealing assembly is external, and both ends are connected to the casing 1 and the bearing box body 8 through short bolts and long bolts 9 respectively. The bearing box does not require an additional welded mounting bracket, which is beneficial to reducing the cost of the fan.

[0032] Referring to Figure 2 and Figure 3 and Figure 4 , the sealing assembly includes a bellows 7, two tetrafluoroethylene gaskets 3 and a spacer layer. Flange ends 2 are fixedly connected to both ends of the bellows 7. Through the flange ends 2, the bellows 7 can be connected to the casing 1 and the bearing box body 8. One side of each of the two tetrafluoroethylene gaskets 3 is lapped on one side of the corresponding flange end 2. The two tetrafluoroethylene gaskets 3 are symmetrically distributed on both sides of the bellows 7. The tetrafluoroethylene gaskets 3 can flatten the invisible unevenness on the surfaces of the casing 1 and the flange end 2, that is, block the gap between the casing 1 and the flange end 2, and prevent the medium from leaking from the connection between the flange ends 2.

[0033] Referring to Figure 2 and Figure 3 , a gland 6 is lapped on one side of the bearing box body 8 close to the bellows 7. The inside of the gland 6 is lapped on the outer surface of the main shaft 10. The gland 6 is fixed on one side of the bearing box body 8, thereby protecting the bearing box body 8. At the same time, there is a margin for replacing the tetrafluoroethylene gaskets 3, aluminum labyrinths 4, dust-proof graphite gaskets 5, and pressing plates 11 with different thicknesses. When the bellows 7 needs to be maintained, only the long bolts 9 and short bolts need to be disassembled, and then the bellows 7, tetrafluoroethylene gaskets 3, aluminum labyrinths 4, dust-proof graphite gaskets 5, and pressing plates 11 can be replaced.

[0034] Referring to Figure 2 and Figure 3 , the spacer layer includes an aluminum labyrinth 4, a dust-proof graphite gasket 5 and a pressing plate 11. The aluminum labyrinth 4 and the dust-proof graphite gasket 5 create an air seal to block the leaked medium in the fan. The aluminum labyrinth 4, the dust-proof graphite gasket 5 and the pressing plate 11 are successively lapped on the outer surface of the main shaft 10. The medium flowing along the outer surface of the main shaft 10 is blocked after hitting the aluminum labyrinth 4 and is prevented from flowing into the bearing box body 8.

[0035] The other side of one of the tetrafluoroethylene gaskets 3 is lapped on the outer surface of the aluminum labyrinth 4, and the other side of the other tetrafluoroethylene gasket 3 is lapped on the outer surface of the casing 1. The two tetrafluoroethylene gaskets 3 are the sealing gaskets for the flange ends 2 to block the gaps between the flange ends 2 and the casing 1 and the aluminum labyrinth 4.

[0036] Refer to Figure 2 、 Figure 3 wherein, on the outer surfaces of one of the flange ends 2, one of the polytetrafluoroethylene gaskets 3, the aluminum labyrinth 4, the dust-proof graphite gasket 5, the gland 6 and the pressing plate 11, a number of through holes one are provided in a circumferential array centered on the central axis of the main shaft 10. Every six corresponding through holes one form a group. Inside each group of through holes one, a long bolt 9 is fixedly connected. On the outer surface of each long bolt 9, two nuts one are fixedly connected. One part of the nuts one is clamped on one side of the pressing plate 11, and the other part of the nuts one is clamped on one side of the gland 6. One end of the long bolt 9 is threadedly connected to the inside of the bearing housing 8, and the other end of the long bolt 9 is clamped on one side of the corresponding flange end 2. The long bolt 9 sequentially passes through the flange end 2 of the bellows 7, the polytetrafluoroethylene gasket 3, the aluminum labyrinth 4, the dust-proof graphite gasket 5, the pressing plate 11 and the gland 6. One end of the long bolt 9 is located inside the bearing housing 8 and is separated by two nuts one. Among them, the flange end 2 of the bellows 7, the polytetrafluoroethylene gasket 3, the aluminum labyrinth 4, the dust-proof graphite gasket 5, and the pressing plate 11 are on one side, and the gland 6 and the bearing housing 8 are on the other side. By tightening the nut two in the middle, the polytetrafluoroethylene gasket 3, the aluminum labyrinth 4, the dust-proof graphite gasket 5, and the pressing plate 11 are locked in the direction close to the flange end 2, and the gland 6 is tightened in the direction close to the bearing housing 8.

[0037] Refer to Figure 2 、 Figure 4 On the outer surface of the other flange end 2 and one side of the casing 1, a number of through holes two are provided in a circumferential array centered on the central axis of the main shaft 10. Every two corresponding through holes two form a group. The short bolts are common bolts, only being short bolts relative to the length of the long bolt 9. Inside each group of through holes two, a short bolt is inserted. On the outer surface of each short bolt, a nut two is fixedly connected. One side of each nut two is clamped on one side of the casing 1. Through the cooperation of the nut two and the short bolt, the flange end 2 of the bellows 7, the polytetrafluoroethylene gasket 3 and the casing 1 are locked tightly, so that the bellows 7 and the casing 1 are connected. When the casing 1 is heated and undergoes displacement or deformation, the bellows 7 can self-compensate radially and axially by ±25 mm, avoiding the displacement of the casing 1 caused by the vibration or thermal deformation of the fan casing 1.

[0038] The implementation principle of the external shaft seal of a ventilator in an embodiment of the present utility model is as follows:

[0039] 1. First, on the fan casing 1, one flange end 2 of the bellows 7 is fixed to the casing 1 with short bolts, and a polytetrafluoroethylene gasket 3 is added in the middle. The other flange end 2 of the bellows 7 is sequentially connected to the polytetrafluoroethylene gasket 3, the aluminum labyrinth 4, the dust-proof graphite gasket 5, and the pressing plate 11, and all of them are connected to the gland 6 and the bearing housing 8 on the bearing box by the long bolt 9;

[0040] 2. The sealing assembly includes a bellows 7, a polytetrafluoroethylene gasket 3, an aluminum labyrinth 4, a dust-proof graphite gasket 5, and a pressing plate 11. The assembly of the aluminum labyrinth 4 and the main shaft 10 is a clearance fit of 0.2 - 0.3 mm, and the assembly of the dust-proof graphite gasket 5 and the main shaft 10 is a contact fit. The sealing assembly is externally placed. The bellows 7 can self-compensate for the deformation of its housing 1. The installation clearance between the aluminum labyrinth 4 and the main shaft 10 can be ensured for a long time, effectively preventing gas leakage.

[0041] The above are all preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention shall be covered within the protection scope of the present invention.

Claims

1. An external shaft seal for a ventilator, characterized in that: It includes a housing (1), a main shaft (10), a bearing box body (8) and a sealing assembly. The housing (1), the sealing assembly and the bearing box body (8) are sequentially lapped on the outer surface of the main shaft (10), and both ends of the sealing assembly are respectively in contact with one side of the housing (1) and the bearing box body (8).

2. The external shaft seal of a ventilator according to claim 1, characterized in that: The sealing assembly includes a corrugated pipe (7), two tetrafluoroethylene gaskets (3) and a spacer layer. Flange ends (2) are fixedly connected to both ends of the corrugated pipe (7). One side of each of the two tetrafluoroethylene gaskets (3) is lapped on the corresponding side of the flange end (2), and the two tetrafluoroethylene gaskets (3) are symmetrically distributed on both sides of the corrugated pipe (7).

3. The external shaft seal of a ventilator according to claim 2, characterized in that: A gland (6) is lapped on one side of the bearing box body (8) close to the corrugated pipe (7), and the inside of the gland (6) is lapped on the outer surface of the main shaft (10).

4. The external shaft seal of a ventilator according to claim 3, characterized in that: The spacer layer includes an aluminum labyrinth (4), a dust-proof graphite gasket (5) and a pressing plate (11). The aluminum labyrinth (4), the dust-proof graphite gasket (5) and the pressing plate (11) are sequentially lapped on the outer surface of the main shaft (10).

5. The external shaft seal of a ventilator according to claim 4, characterized in that: The other side of one of the tetrafluoroethylene gaskets (3) is lapped on the outer surface of the aluminum labyrinth (4), and the other side of the other tetrafluoroethylene gasket (3) is lapped on the outer surface of the housing (1).

6. The external shaft seal of a ventilator according to claim 5, characterized in that: A number of through holes one are provided on the outer surfaces of one of the flange ends (2), one of the tetrafluoroethylene gaskets (3), the aluminum labyrinth (4), the dust-proof graphite gasket (5), the gland (6) and the pressing plate (11), which are arranged in a circumferential array with the central axis of the main shaft (10) as the center. Every six corresponding through holes one form a group, and a long bolt (9) is fixedly connected inside each group of through holes one. Two nuts one are fixedly connected to the outer surface of each long bolt (9). One part of the nuts one is clamped on one side of the pressing plate (11), and the other part of the nuts one is clamped on one side of the gland (6). One end of the long bolt (9) is threadedly connected to the inside of the bearing box body (8), and the other end of the long bolt (9) is clamped on one side of the corresponding flange end (2).

7. The external shaft seal of a ventilator according to claim 6, characterized in that: A number of through holes two are provided on the outer surface of the other flange end (2) and one side of the housing (1), which are arranged in a circumferential array with the central axis of the main shaft (10) as the center. Every two corresponding through holes two form a group, and a short bolt is inserted inside each group of through holes two. A nut two is fixedly connected to the outer surface of each short bolt, and one side of each nut two is clamped on one side of the housing (1).

Images