DE102022134084B3 - Mechanical seal arrangement - Google Patents

Abstract

The invention relates to a mechanical seal arrangement (1) comprising: a mechanical seal (2) with a rotating sliding ring (3) and a stationary sliding ring (4), which define a sealing gap (5) between their sliding surfaces, a through-opening (40) in the stationary sliding ring (4), which is designed to guide a barrier fluid into the sealing gap (5) between the sliding surfaces, wherein the through-opening (40) has an opening (41) directed towards the sealing gap, wherein at the sealing gap (5) the opening of the through-opening (41) divides the sealing gap into a first annular sealing gap region (51) and a second annular sealing gap region (52), wherein in the first sealing gap region (51) at least one of the sliding surface regions located there is a conveying arrangement (6), wherein the conveying arrangement (6) is designed to convey barrier fluid supplied via the through-opening into a pressure chamber (7) in which a first pressure P1 prevails, and wherein in an anteroom (8) at the stationary sliding ring (4), through which the Barrier fluid is supplied to the passage opening (40), a second pressure P2 prevails which is smaller than the first pressure P1.

Description

The present invention relates to a mechanical seal arrangement with a leakage reduced by orders of magnitude and reduced barrier fluid consumption compared to the previously known solutions.

Mechanical seal arrangements are known in various designs from the state of the art. In order to prevent the medium to be sealed from leaking through a sealing gap between the sliding rings of a mechanical seal, it is known to supply a sealing fluid to seal the mechanical seal. Easily accessible sealing fluids, such as nitrogen, cannot be used for sealing in certain sealing applications, as they would contaminate the medium to be sealed. In particular, in closed circuits with coolants, such as propane or ammonia, the introduction of nitrogen through the leak through the sealing gap is always critical. It is therefore necessary to find solutions that can reliably seal such media. From the CN 106 122 484 A A mechanical seal arrangement with a mechanical seal is known which has a conveying arrangement on the rotating seal ring which can convey barrier fluid into a space via a through opening.

The object of the present invention is to provide a mechanical seal arrangement which, with a simple structure and easy, cost-effective manufacture, has a reduced leakage of barrier fluid and reduced barrier fluid consumption during operation and also fulfils difficult sealing tasks.

This object is achieved by a mechanical seal arrangement having the features of claim 1, 2 or 3. The subclaims show preferred developments of the invention.

The mechanical seal arrangement according to the invention with the features of claim 1 has the advantage that a secure seal is possible with a very compact design of the mechanical seal. This also achieves a leakage reduced by orders of magnitude of 10 ² or more. The consumption of barrier fluid can also be significantly reduced. This is achieved according to the invention in that the mechanical seal arrangement makes it possible to keep a supply pressure of the barrier fluid very close to a pressure of one atmosphere, in particular at a pressure of a maximum of twice atmospheric pressure, more particularly 10% above atmospheric pressure or even below. The mechanical seal arrangement comprises a mechanical seal with a rotating slide ring and a stationary slide ring, which define a sealing gap between their sliding surfaces. A through opening is formed on the stationary slide ring, which is designed to guide barrier fluid into the sealing gap between the sliding surfaces. The through opening has an opening directed towards the sealing gap. The opening of the through opening divides the sealing gap into a first annular sealing gap area and a second annular sealing gap area. In the first sealing gap area, a conveying arrangement is arranged on at least one of the sliding surface areas located there, which is designed to convey barrier fluid supplied via the through-opening into a pressure chamber in which a first pressure P1 prevails. In an antechamber which lies in front of the through-opening on a rear side of the stationary sliding ring in the flow direction of the barrier fluid and through which barrier fluid is supplied to the through-opening, there is a second pressure P2 which is lower than the first pressure P1.

A minimal amount of sealing gas then flows through the second sealing gap area towards the atmospheric area or alternatively towards a flare system, since there is only a minimal pressure difference between the area at the mouth of the passage opening and the atmospheric area. The invention thus also enables a significant reduction in the amount of sealing fluid with minimal installation space.

A further advantage of the invention is that no complex supply systems for the barrier fluid are necessary, since this can be supplied at a very low pressure close to atmospheric pressure.

According to the invention, the mechanical seal arrangement further comprises a second mechanical seal arranged in series with the first mechanical seal as a safety seal. The safety seal comprises a rotating and a stationary mechanical seal, which define a sealing gap between their sliding surfaces. An intermediate space is connected to the first and second mechanical seals in a fluid-connecting manner. At least one of the mechanical seals of the second mechanical seal has a conveying arrangement on a sliding surface in order to convey air from an atmospheric region through the sealing gap of the second mechanical seal into the intermediate space. A branch line to a flare system or the like preferably leads off from the intermediate space.

This has the further advantage that air can pass through the second mechanical seal at such a high rate tion can be fed into the intermediate space so that, for example, in the case of a flammable barrier fluid, a ratio of the barrier fluid and the supplied air is selected such that no ignitable mixture can arise and this mixture can then be released safely, for example via a flare system, or can be catalytically burned.

Alternatively, the mechanical seal arrangement comprises a second mechanical seal arranged in series with the first mechanical seal as a safety seal, which has a rotating sliding ring and a stationary sliding ring, which define a sealing gap between their sliding surfaces, wherein an intermediate space is connected in a fluid-connecting manner to the first and second mechanical seals, wherein at least one of the sliding rings of the second mechanical seal has a conveying arrangement on a uniform surface in order to supply an additional barrier fluid into a barrier space which is arranged on the second mechanical seal. The barrier space is separated from the intermediate space between the first and second mechanical seals by a further additional seal, preferably a labyrinth seal. The additional barrier fluid is preferably nitrogen. The conveying arrangement in one of the sliding rings of the second mechanical seal conveys the additional barrier fluid from the barrier space through the sealing gap of the second mechanical seal to the atmospheric region. Since nitrogen is used as the additional barrier fluid, it can be prevented that a component that is harmful to the environment can reach the atmosphere. A fourth pressure in the barrier space is greater than a fifth pressure in the intermediate space between the first and second mechanical seals. Thus, the additional barrier fluid flows via the additional seal from the barrier chamber to the intermediate chamber.

According to a further preferred alternative embodiment of the invention, the mechanical seal arrangement further comprises a second mechanical seal arranged in series with the first mechanical seal as a safety seal. The second mechanical seal comprises a stationary mechanical ring which has a through-opening through which an additional barrier fluid can be conveyed through the through-opening to the sealing gap of the second mechanical seal. The second mechanical seal is constructed in the same way as the first mechanical seal, so that the additional barrier fluid can be guided into the space between the first and second mechanical seals by the conveying arrangement of the second mechanical seal. Due to the pressure build-up in the sealing gap of the second mechanical seal by the conveying arrangement, it is again achieved that the pressure of the additional barrier fluid in front of the through-opening can be very low and only small amounts of the additional barrier fluid or no amounts can reach the atmosphere side.

Preferably, the conveying arrangement, which is arranged on at least one of the sliding rings, comprises a plurality of conveying grooves. The conveying grooves are preferably sickle-shaped and preferably designed with a depth that changes in the radial direction.

Particularly preferably, conveying grooves are arranged in both sliding surfaces of the rotating and stationary sliding rings.

In order to prevent as far as possible that barrier fluid can flow in the direction of the atmosphere side or to a flare system via the second sealing gap area in the sealing gap of the mechanical seal, the second sealing gap area preferably has a groove arrangement on at least one of the sliding rings to reduce the flow of barrier fluid. The groove arrangement is preferably a circumferential barrier groove with a constant depth or a changing depth.

Particularly preferably, the second sealing gap region is arranged radially inside the mouth of the through opening in the stationary sliding ring.

The mechanical seal arrangement further preferably comprises a barrier fluid line which leads from a pressure region of the medium to be sealed to the antechamber on the stationary mechanical seal ring. The antechamber is preferably provided on a rear side of the stationary mechanical seal ring. The medium to be sealed can thus be used as the barrier fluid, whereby the costs for the barrier fluid and necessary system costs for the barrier fluid arrangement can be further reduced.

Preferably, the second pressure P2 in the antechamber is lower than a third pressure P3 in the pressure range of the medium to be sealed. The pressure reduction from the third pressure P3 to the second pressure P2 can be carried out by suitable devices, for example pressure reducers or the like. Furthermore, a cleaning device is also preferably arranged in the barrier fluid line in order to clean the barrier fluid. This removes impurities from the barrier fluid which could cause damage to the mechanical seal when the medium to be sealed is used as the barrier fluid.

According to a further preferred embodiment of the invention, the mechanical seal arrangement further comprises a reservoir which is filled with pressurized barrier fluid and which can be brought into fluid communication with the antechamber. The reservoir serves as a safety device, in order to be able to continue to supply the mechanical seal with sealing fluid in the event of a failure of the actual sealing fluid or maintenance on a filter unit. Since the invention significantly reduces the consumption of sealing fluid, the reservoir can be designed to be very small. The reservoir is preferably a nitrogen bottle. Despite such a small reservoir, such as the nitrogen bottle with a small volume, the operation of the mechanical seal can still be maintained over a longer period of time, in particular several hours or days, due to the low consumption of sealing fluid, in order to enable the machine in which the mechanical seal seals to stop in the event of a malfunction, for example.

According to an alternative embodiment of the invention, the mechanical seal arrangement further comprises a nitrogen generator which is designed to generate nitrogen as a barrier fluid from the air and to supply it to the antechamber on the stationary mechanical seal ring. Due to the low barrier fluid consumption, the nitrogen generator can be dimensioned very small. The nitrogen generator is preferably protected from excessive pressure by means of a check valve.

The mechanical seal arrangement further preferably comprises a check valve which is arranged in the barrier fluid line. The check valve is arranged in the barrier fluid line as close as possible to the antechamber of the stationary mechanical seal, in particular such that no further devices are present between the check valve and the antechamber. The check valve prevents fluid from flowing back from the antechamber in the direction of the source of the barrier fluid and protects components of the barrier fluid supply from high pressure in the event of a failure of the mechanical seal direction.

The mechanical seal arrangement is preferably a gas-lubricated mechanical seal arrangement. The additional sealing gas is preferably nitrogen, which is obtained from the ambient air using a nitrogen generator. Since the additional sealing fluid only needs to have a low pressure, since the main pressure generation for the sealing fluid takes place through the conveying arrangement in the sealing gap of the mechanical seal, only a very small amount of additional sealing fluid is used.

• 1 eine schematische Schnittansicht einer Gleitringdichtungsanordnung gemäß einem ersten Ausführungsbeispiel der Erfindung,
• 2 eine schematische Schnittansicht einer Gleitringdichtungsanordnung gemäß einem zweiten Ausführungsbeispiel der Erfindung,
• 3 eine schematische Schnittansicht einer Gleitringdichtungsanordnung gemäß einem dritten Ausführungsbeispiel der Erfindung,
• 4 eine schematische Schnittansicht einer Gleitringdichtungsanordnung gemäß einem vierten Ausführungsbeispiel der Erfindung, und
• 5 eine schematische Schnittansicht einer Gleitringdichtungsanordnung gemäß einem fünften Ausführungsbeispiel der Erfindung.

Preferred embodiments of the invention are described in detail below with reference to the accompanying drawing. In the drawing:

• 1 a schematic sectional view of a mechanical seal arrangement according to a first embodiment of the invention,
• 2 a schematic sectional view of a mechanical seal arrangement according to a second embodiment of the invention,
• 3 a schematic sectional view of a mechanical seal arrangement according to a third embodiment of the invention,
• 4 a schematic sectional view of a mechanical seal arrangement according to a fourth embodiment of the invention, and
• 5 a schematic sectional view of a mechanical seal arrangement according to a fifth embodiment of the invention.

The following is based on reference to 1 a mechanical seal arrangement 1 according to a first preferred embodiment of the invention is described in detail.

As from 1 As can be seen, the mechanical seal arrangement 1 comprises a mechanical seal 2 with a rotating sliding ring 3 with a first sliding surface 3a and a stationary sliding ring 4 with a second sliding surface 4a. A sealing gap 5 is defined between the first and second sliding surfaces.

A through-opening 40 is arranged in the stationary sliding ring 4 and is designed to supply a barrier fluid into the sealing gap 5 between the sliding surfaces of the sliding rings. The through-opening 40 runs in a straight line from a rear side of the stationary sliding ring to the sealing gap 5. At the sealing gap 5, the through-opening 40 has an opening 41 directed towards the sealing gap.

The mouth 41 on the sealing gap 5 divides the latter into a first annular sealing gap region 51 and a second annular sealing gap region 52. In this embodiment, the first annular sealing gap region 51 is arranged radially outside the mouth 41 and the second annular sealing gap region 52 is arranged radially inside the mouth 41.

The rotating slide ring 3 is connected to a shaft 13 running in the axial direction X-X by means of a slide ring carrier 31. The slide ring seal 2 seals a product area 16 from an atmospheric area 17 on the shaft 13. In this embodiment, the shaft 13 drives a compressor 15, which is sealed from the atmospheric area 17 by means of the slide ring seal arrangement 1.

The stationary sliding ring 4 is arranged on a housing 14.

How to continue 1 As can be seen, a conveyor arrangement 6 is arranged on the first sliding surface 3a of the rotating sliding ring 3. The conveyor The conveying arrangement 6 is provided in the first sealing gap area 51 of the sealing gap. The conveying arrangement 6 comprises a plurality of conveying grooves 61. The conveying grooves 61 are arranged along the circumference at the same distance from one another and are geometrically constructed in the same way. As can be seen from 1 As can be seen, a depth of the conveying grooves 61 changes in such a way that the depth decreases radially outwards. The conveying grooves 61 can be straight or sickle-shaped.

At the second sealing gap region 52, the rotating sliding ring 3 has a groove arrangement 9 for reducing a flow of barrier fluid in the direction of the atmospheric region 17. The groove arrangement 9 is preferably a circumferential annular groove with a constant, rectangular cross-section, or alternatively with any other arbitrary geometric cross-section.

How to continue 1 As can be seen, an antechamber 8 is provided on a rear side 4b of the stationary sliding ring 4. The sealing fluid is supplied to the antechamber 8 via a sealing fluid line 10, which branches off from the medium area 16 of the compressor. A cleaning unit 11 and a pressure reducer 12 are arranged in series in the sealing fluid line 10 for cleaning the possibly contaminated medium to be sealed. The pressure reducer 12 is designed to reduce the medium under high pressure P3 to a low second pressure P2.

By means of the conveying arrangement 6 in the rotating sliding ring 3, the barrier fluid is conveyed radially outwards in the direction of a pressure chamber 7. A first pressure P1 prevails in the pressure chamber 7.

The second pressure P2 in the anteroom 8 is slightly greater than the atmospheric pressure P0 in the atmospheric region 17. Preferably, the second pressure P2 is a maximum of 10%, preferably a maximum of 5%, preferably a maximum of 2% greater than the atmospheric pressure P0. It should be noted that it is theoretically also possible for the second pressure P2 to be a pressure below the atmospheric pressure P0.

The stationary sliding ring 4 is sealed against the housing 14 by means of a first secondary seal 71 and a second secondary seal 72. Only the first secondary seal 71 on the stationary sliding ring is subjected to pressure from the pressure chamber 7, so that very good axial mobility of the stationary sliding ring 4 is ensured. The rotating sliding ring 3 is sealed at the back by means of a third secondary seal 73 on the sliding ring carrier 31.

The function of the mechanical seal arrangement according to the invention is as follows. Barrier fluid is branched off from the medium region 16 via the barrier fluid line 10 to the antechamber 8 and reduced from the third pressure P3 to the second pressure P2. The barrier medium then flows from the antechamber 8 through the through opening 40 into the sealing gap 5. Due to the rotation of the rotating slide ring 3, most of the barrier fluid supplied to the sealing gap is conveyed radially outwards. The conveying arrangement increases the pressure of the barrier fluid, which is conveyed radially outwards into the pressure chamber 7, preferably by a factor of 50 or more. Furthermore, the groove arrangement 9 prevents large quantities of barrier fluid, which has a similar pressure level to the atmospheric pressure P0 due to the low second pressure P2, from flowing radially inwards towards the atmospheric region 17. This is mainly achieved by the blocking groove arrangement 9 in the rotating slide ring. The groove arrangement 9 can be designed such that during operation no barrier fluid flows via the second sealing gap region 52 in the direction of the atmospheric region 17.

The mechanical seal arrangement 1 according to the invention thus has a very compact design. A separate additional sealing fluid device is not necessary since the medium to be sealed can be used as the sealing fluid.

If the supply of barrier fluid via the barrier fluid line 10 from the medium area 16 is no longer possible, a reservoir 18 connected to the barrier fluid line 10 is provided. The reservoir 18 stores barrier fluid under pressure and forms an emergency reserve of barrier fluid to replace the barrier fluid missing from the medium area 16. Since the mechanical seal arrangement according to the invention only uses very little barrier fluid due to the very low second pressure P2, operation can be maintained for several hours or days using the barrier fluid stored in the reservoir 18. The reservoir 18 can therefore be designed to be very small and is preferably a gas bottle, in particular filled with nitrogen. The invention therefore also enables emergency operation without complex redundant devices.

As from 1 As can be seen, a switching device 81 is provided at an opening of the connecting line between the reservoir 18 and the barrier fluid line 10, which can be designed as a 3/2-way valve, for example. The switching device 81 prevents barrier fluid from flowing in the direction of the medium area 16 when it is removed from the reservoir 18. Furthermore, a check valve 80 is arranged in the barrier fluid line 10. The check valve 80 prevents the barrier fluid from flowing back from the antechamber 8 in the direction of the medium area 16. As can be seen from 1 As can be seen, the setback valve 80 is arranged in the barrier fluid line 10 in such a way that no further devices are arranged in the barrier fluid line 10 between the antechamber 8 and the check valve 80. In other words, the check valve 80 is directly in fluid communication with the antechamber 8. The blocking direction of the check valve 80 is thus opposite to the usual conveying direction in the barrier fluid line 10 (see arrows in 1 ).

Furthermore, the mechanical seal arrangement 1 according to the invention can ensure that, due to the use of the medium to be sealed as a sealing gas, sealing is also possible in closed circuits with coolant using a process-compatible sealing fluid. Since the sealing fluid may be critical for the environment, the very low pressure level P2, which is close to the atmospheric pressure P0, can also prevent the sealing fluid from flowing out inadmissibly to the atmospheric region 17. If the second pressure P2 is below the atmospheric pressure P0, a flow reversal can even be achieved in the second sealing gap region 52, so that air is sucked into the sealing gap 5 via the second sealing gap region 52 and leakage of the sealing fluid into the environment can thus be reliably prevented.

2 shows a mechanical seal arrangement 1 according to a second embodiment of the invention. Identical or functionally identical parts are designated with the same reference numerals as in the first embodiment. In contrast to the first embodiment, in the second embodiment a sealing fluid obtained from ambient air is used. This can be done, for example, using a nitrogen generator 28, so that nitrogen is supplied as a sealing fluid to the antechamber 8. Since the second pressure P2 is close to the atmospheric pressure P0 and is only minimally greater than the atmospheric pressure P0, no additional, energy-consuming compression of the sealing fluid needs to be provided. Furthermore, in contrast to the first embodiment, in the second embodiment the conveying arrangement 6 is provided with a row of first conveying grooves 61 in the rotating slide ring 3 and a row of second conveying grooves 62 in the stationary slide ring 4. This allows the pressure increase in the sealing gap to be further increased during operation of the mechanical seal. It should be noted that, if the medium to be sealed allows it, instead of the nitrogen generator in the sealing fluid line 10, air can also simply be compressed to the second pressure P2 and used as the sealing fluid. Otherwise, this embodiment corresponds to the first embodiment, so that reference can be made to the description given there.

3 shows a mechanical seal arrangement 1 according to a third embodiment of the invention. Identical or functionally identical parts are again designated with the same reference numerals as in the first embodiment.

As from 3 As can be seen, the mechanical seal arrangement 1 of the third embodiment comprises a second mechanical seal 20 as a safety seal. The first mechanical seal 2 and the second mechanical seal 20 are arranged in series on the shaft 13 in order to seal a medium region 16 from the atmospheric region 17 on the shaft 13. A gap 19 is provided between the first and second mechanical seal on the shaft.

The second mechanical seal 20 comprises a rotating sliding ring 21 and a stationary sliding ring 22, which is arranged axially movable on the housing 14. A sealing gap 23 is arranged in a known manner between the rotating and the stationary sliding ring. The rotating sliding ring 21 is connected to the shaft 13 by means of a sliding ring carrier 21a.

A conveying arrangement 24 with a plurality of conveying grooves provided along the circumference is arranged in the rotating slide ring 21. During rotation, the conveying arrangement 24 ensures that air is conveyed from the atmospheric region 17 via the sealing gap 23 to the intermediate space 19 and thus no leakage can occur via the sealing gap 23 of the second mechanical seal 20 in the direction of the atmospheric region 17. In this case, the pressure is also increased by the conveying arrangement 24 to a pressure greater than the atmospheric pressure P0.

The first mechanical seal 2 is constructed in the same way as described in the first embodiment. The intermediate space 19 is in fluid communication with the second sealing gap region 52 and the sealing gap 23, so that in the intermediate space 19 a mixing of the air supplied via the second mechanical seal 20 and the very small leakage via the second sealing gap region 52 takes place. This can prevent, for example, if the air is conveyed at a high rate via the second mechanical seal 20, a mixing of the minimal leakage and the air in the case of a flammable barrier fluid at the first mechanical seal 2, so that no ignitable mixture is formed by the dilution. The mixture can then, for example, be safely delivered to a flare system 100. The 3 The schematically illustrated sealing fluid line 10 can use the medium to be sealed as the sealing fluid, as in the first embodiment, or alternatively another sealing fluid. For emergencies, A reservoir 18 filled with a barrier fluid is provided around the housing. Otherwise, this embodiment corresponds to the previous embodiments, so that reference can be made to the description given there.

4 shows a mechanical seal arrangement 1 according to a fourth embodiment of the invention, wherein again identical or functionally identical parts are designated by the same reference numerals as in the first embodiment.

The fourth embodiment essentially corresponds to the third embodiment and also has a second mechanical seal 20 as a safety seal. However, a second barrier fluid line 25 is also provided here, which supplies a second barrier fluid into a barrier chamber 27 in front of the second mechanical seal 20. The second barrier fluid line 25 is separated from the first barrier fluid line 10. The second mechanical seal 20 comprises a conveying arrangement 24 in the rotating slide ring 21, which leads radially inwards so that the second barrier fluid can be conveyed from the second barrier fluid line 25 through the sealing gap 23 to the atmospheric region 17. The second barrier fluid is thus a medium that is harmless to the atmosphere.

Furthermore, an additional seal is provided between the blocking chamber 27 and the intermediate space 19 between the first mechanical seal 2 and the second mechanical seal 20, which is designed as a labyrinth seal 26. Similar to the second exemplary embodiment, the second blocking fluid can be nitrogen or air. A fourth pressure P4 in the blocking chamber 27 is greater than a fifth pressure P5 in the intermediate space 19. This prevents a medium that may have leaked into the intermediate space 19 from escaping to the atmosphere. The media mixture can thus be diverted from the intermediate space 19 to a flare system 100. The first mechanical seal 2 again corresponds to the mechanical seal described in the first exemplary embodiment. Otherwise, this exemplary embodiment corresponds to the previous exemplary embodiments, so that reference can be made to the description given there.

5 shows a mechanical seal arrangement 1 according to a fifth embodiment of the invention. Identical or functionally identical parts are again designated with the same reference numerals as in the previous embodiments.

The fifth embodiment essentially corresponds to the fourth embodiment, with the second seal 20 being designed differently from the fourth embodiment. In the fifth embodiment, the second mechanical seal 20 is constructed in the same way as the first mechanical seal 2. The reference numerals of the second mechanical seal are the same as in the first mechanical seal, but marked with an apostrophe. Second barrier fluid is fed via the second barrier fluid line 25 to the rear of the stationary slide ring 4' into the through opening 40'. The through opening 40' opens at the mouth 41' on the sealing gap 5' between the stationary slide ring 4' and a rotating slide ring 3'. A conveying arrangement 6' with conveying grooves 61' is provided on the rotating slide ring 3' on the first sealing gap region 51'. A corresponding barrier groove arrangement 9' is provided on the second sealing gap region 52'. The second barrier fluid is preferably nitrogen. As a result, any possible leakage can be easily discharged via the second sealing gap region 52' to the atmospheric region 17. Otherwise, this embodiment corresponds to the fourth embodiment, so that reference can be made to the description given there.

List of reference symbols

1

Mechanical seal arrangement

2

Mechanical seal

3

rotating sliding ring

3a

first sliding surface

4

stationary sliding ring

4a

second sliding surface

4b

back

5

Sealing gap

6

Conveyor arrangement

7

Printing room

8th

Anteroom

9

Groove arrangement

10

Barrier fluid line

11

Cleaning unit

12

Pressure reducer

13

Wave

14

Housing

15

compressor

16

Medium area

17

Atmosphere area

18

Storage / gas bottle

19

Space

20

second mechanical seal / safety seal

21

rotating sliding ring

21a

Slide ring carrier

22

stationary sliding ring

23

Sealing gap

24

Conveyor arrangement

25

second barrier fluid line

26

Additional seal / labyrinth seal

27

Restricted area

28

Nitrogen generator

31

Slide ring carrier

40

Passage opening

41

mouth

51

first sealing gap area

52

second sealing gap area

61

first conveyor groove

62

second conveyor groove

71, 72, 73

first, second and third secondary seal

80

check valve

81

Switching device

100

Flare system

P0

Atmospheric pressure

P1, P2, P3, P4, P5

first, second, third, fourth and fifth printing

X-X

Axial direction

Claims (12)

Mechanical seal arrangement (1) comprising: - a mechanical seal (2) with a rotating sliding ring (3) and a stationary sliding ring (4), which define a sealing gap (5) between their sliding surfaces, - a through-opening (40) in the stationary sliding ring (4), which is designed to guide a barrier fluid into the sealing gap (5) between the sliding surfaces, wherein the through-opening (40) has an opening (41) directed towards the sealing gap, - wherein at the sealing gap (5) the opening of the through-opening (41) divides the sealing gap into a first annular sealing gap region (51) and a second annular sealing gap region (52), - wherein in the first sealing gap region (51) a conveying arrangement (6) is arranged on at least one of the sliding surface regions located there, - wherein the conveying arrangement (6) is designed to convey barrier fluid supplied via the through-opening into a pressure chamber (7) in which a first pressure P1 prevails, and - wherein in an anteroom (8) at the stationary slide ring (4), through which the blocking fluid is supplied to the through opening (40), a second pressure P2 prevails which is lower than the first pressure P1, and further comprising a first mechanical seal (2) and a second mechanical seal (20) as a safety seal, which are arranged in series on a component to be sealed, - wherein the second mechanical seal (20) has a rotating slide ring (21) and a stationary slide ring (22), which define a sealing gap (23) between their sliding surfaces, wherein an intermediate space (19) is connected in a fluid-connecting manner to the first mechanical seal (2) and the second mechanical seal (20), and - wherein at least one of the slide rings of the second mechanical seal (20) has a conveying arrangement (24) on a sliding surface in order to convey air from an atmospheric region (17) into the intermediate space (19). Mechanical seal arrangement (1) comprising: - a mechanical seal (2) with a rotating sliding ring (3) and a stationary sliding ring (4), which define a sealing gap (5) between their sliding surfaces, - a through-opening (40) in the stationary sliding ring (4), which is designed to guide a barrier fluid into the sealing gap (5) between the sliding surfaces, wherein the through-opening (40) has an opening (41) directed towards the sealing gap, - wherein at the sealing gap (5) the opening of the through-opening (41) divides the sealing gap into a first annular sealing gap region (51) and a second annular sealing gap region (52), - wherein in the first sealing gap region (51) on at least one of the sliding surface regions located there, a conveying arrangement (6) is arranged, - wherein the conveying arrangement (6) is designed to convey barrier fluid supplied via the through-opening into a pressure chamber (7) in which a first pressure P1 prevails, and - wherein in an anteroom (8) on the stationary sliding ring (4), through which the blocking fluid is supplied to the through-opening (40), a second pressure P2 prevails which is lower than the first pressure P1, further comprising a first mechanical seal (2) and a second mechanical seal (20) as a safety seal, which are arranged in series on a component to be sealed, wherein the second mechanical seal (20) has a rotating slide ring (21) and a stationary slide ring (22) which define a sealing gap (23) between their sliding surfaces, - wherein an intermediate space (19) is connected in a fluid-connecting manner to the first mechanical seal (2) and the second mechanical seal (20), and wherein at least one of the sliding rings of the second mechanical seal (20) has a conveying arrangement (24) on a sliding surface in order to convey an additional barrier fluid from a barrier space (27) to the atmospheric region (17), - wherein the barrier space (27) is arranged on the second mechanical seal (20), and - wherein the barrier space (27) is separated from the intermediate space (19) by an additional seal (26). Mechanical seal arrangement (1) comprising: - a mechanical seal (2) with a rotating sliding ring (3) and a stationary sliding ring (4), which define a sealing gap (5) between their sliding surfaces, - a through-opening (40) in the stationary sliding ring (4), which is designed to guide a barrier fluid into the sealing gap (5) between the sliding surfaces, wherein the through-opening (40) has an opening (41) directed towards the sealing gap, - wherein at the sealing gap (5) the opening of the through-opening (41) divides the sealing gap into a first annular sealing gap region (51) and a second annular sealing gap region (52), - wherein in the first sealing gap region (51) a conveying arrangement (6) is arranged on at least one of the sliding surface regions located there, - wherein the conveying arrangement (6) is designed to convey barrier fluid supplied via the through-opening into a pressure chamber (7) in which a first pressure P1 prevails, and - wherein in an anteroom (8) at the stationary slide ring (4), through which the blocking fluid is supplied to the through opening (40), a second pressure P2 prevails which is lower than the first pressure P1, further comprising a first mechanical seal (2) and a second mechanical seal (20) as a safety seal, which are arranged in series on a component to be sealed, - wherein the second mechanical seal (20) has a rotating slide ring (21) and a stationary slide ring (22), which define a sealing gap (23) between their sliding surfaces, wherein an intermediate space (19) is connected in a fluid-connecting manner to the first mechanical seal (2) and the second mechanical seal (20), and - wherein at least one of the slide rings of the second mechanical seal (20) has a conveying arrangement (24) on a sliding surface in order to convey an additional blocking fluid supplied to the sealing gap (5`) through a through opening (40') in the stationary slide ring (4`) from the sealing gap (5`) to the intermediate space (19). Mechanical seal arrangement according to one of the preceding claims, wherein the conveying arrangement (6) comprises a plurality of conveying grooves (61) arranged in the circumferential direction. Mechanical seal arrangement according to Claim 4 , whereby the conveying grooves are arranged in both sliding surfaces of the rotating and stationary sliding ring. Mechanical seal arrangement according to one of the preceding claims, wherein in the second sealing gap region (52) on at least one of the sliding rings a groove arrangement (9) for reducing a flow of barrier fluid in the opposite direction to the conveying direction in the first sealing gap region (51) is arranged. Mechanical seal arrangement according to one of the preceding claims, wherein a barrier fluid line (10) for supplying barrier fluid to the through opening (40) connects a media region (16) of the medium to be sealed with the antechamber (8). Mechanical seal arrangement according to Claim 7 , wherein the second pressure P2 in the anteroom (8) is smaller than a third pressure P3 in the media area (16). Mechanical seal arrangement according to one of the preceding claims, further comprising a reservoir (18) which is filled with pressurized barrier fluid, wherein the reservoir is connectable to the antechamber (8) and is provided as an emergency device in order to supply the mechanical seal (2) with barrier fluid in an emergency. Mechanical seal arrangement according to one of the preceding claims, further comprising a nitrogen generator (28) which is configured to generate nitrogen as a barrier fluid from the ambient air and to supply it to the antechamber (8). Mechanical seal arrangement according to Claim 2 or 3 , where the additional barrier fluid is nitrogen or air. Mechanical seal arrangement according to one of the preceding claims, further comprising a check valve (80) which is arranged in the barrier fluid line (10) and prevents a backflow of the barrier fluid from the antechamber (8).

Images