Floating ring seal

Abstract

The invention relates to a floating ring seal comprising: a floating ring (2) having a radial sealing surface (20) designed for sealing against a rotating component (3); a multi-part housing (4) which accommodates the floating ring, wherein an annular intermediate space (6) is provided between the housing and the floating ring (2); and a rotation-preventing unit (5) designed to prevent the floating ring (2) from rotating with the rotating component (3), wherein the rotation-preventing unit (5) has a flexible element (50), a first fixing device (51) and a second fixing device (52), wherein the first fixing device (51) fixes the flexible element to the floating ring (2) and the second fixing device (52) fixes the flexible element to the housing (4), and wherein the flexible element (50) is designed to allow axial and radial movements of the floating ring (2).

Description

[0001] Floating ring seal

[0002] Description

[0003] The present invention relates to a floating ring seal, in particular a carbon vibrating ring seal, with an improved rotation locking unit which prevents the floating ring from rotating with a rotating component and enables axial and radial movement of the floating ring in order to be able to follow movements of a rotating component.

[0004] Floating ring seals are known in various designs from the prior art. Floating ring seals are used, for example, to seal shafts that rotate at high speeds. The floating ring seal sits floating on the shaft and has as little radial clearance as possible to minimize leakage through the floating ring seal. Due to the relatively small radial clearance between the rotating shaft and the floating ring seal, there is a risk of the floating ring seal rotating. Furthermore, radial and / or axial movements of the shaft can occur during operation, which the floating ring seal must follow without causing damage to the radial sealing surface of the floating ring seal.

[0005] It is therefore an object of the present invention to provide a floating ring seal which, with a simple structure and simple, cost-effective manufacture, can reliably prevent the floating ring seal from rotating with a rotating component and can also follow deflections of a rotating component.

[0006] This object is achieved by a floating ring seal having the features of claim 1. The subclaims show preferred developments of the invention.

[0007] The floating ring seal according to the invention with the features of claim 1 has the advantage that, on the one hand, co-rotation of the floating ring seal during operation with a rotating component can be prevented and, on the other hand, deflections of the rotating component are possible both in the radial direction and in the axial direction of the rotating component without the floating ring seal being damaged, since the floating ring seal can follow the corresponding deflections. This is achieved according to the invention in that the floating ring seal has a floating ring with a radial sealing surface which is designed to seal against a rotating component, in particular a shaft. Furthermore, the floating ring seal comprises a multi-part housing which encloses the floating ring on an outer circumference of the floating ring. An annular intermediate space is provided between the housing and the floating ring.A rotation-locking unit is provided which is designed to prevent rotation of the floating ring with the rotating component and to enable movements in the radial and axial directions. The rotation-locking unit comprises a flex element and a first and a second fixing device. The first fixing device fixes the flex element to the floating ring and the second fixing device fixes the flex element to the housing. The flex element is a flexible, movable component which enables movements of the floating ring in the radial and axial directions. By fixing the flex element on the one hand to the housing and on the other hand to the floating ring, rotation of the floating ring during operation with the rotating component is also prevented. In this way, a radial sealing gap, which is provided for sealing between the floating ring and the rotating component, can be selected to be as small as possible.This results in very low leakage across the radial sealing gap between the floating ring and the rotating component. This significantly improves the performance of the floating ring seal.

[0008] Through the clever use of the flexible element, which runs through the gap, the floating ring seal can be constructed very simply, significantly reducing material usage and, in particular, the manufacturing costs of the floating ring seal. Nevertheless, the floating ring seal offers the necessary robustness and can provide anti-twist protection for the floating ring seal.

[0009] Preferably, the flex element is a rope-like element, preferably a rope or a wire or a cord, made of a tear-resistant material.

[0010] A rope-like flex element also has the advantage that it can be easily adapted to different floating ring seals by simply selecting the length of the flex element.

[0011] By using a rope-like flex element, the flex element can preferably be aligned exclusively in the radial direction of the floating ring. This results in a particularly compact design.

[0012] The rope-like flexible element preferably has at least one loop or bend, or the like, in particular exclusively in the radial direction, which allows the floating ring seal to easily follow, in particular, radial movements of the rotating component. To achieve this, simply select the appropriate length of the rope-like flexible element.

[0013] Further preferably, the second fixing device, which fixes the flexible element to the housing, is arranged at a joint between housing parts of the multi-part housing. In other words, the second fixing element fixes the flexible element at a separation point of the multi-part housing. This enables simple and secure fixation of the flexible element to the housing.

[0014] The second fixing device is preferably arranged in a recess in a housing part, wherein the recess is connected by a groove to an outer surface of the housing facing the floating ring. The flex element is guided through the groove and fixed in the recess by the second fixing device.

[0015] Particularly preferably, the first and second fixing devices are designed as a sleeve, wherein the sleeve has an internal thread with at least one lateral through-opening. The first and second fixing devices further comprise a screw element, for example a grub screw, which fixes a flexible element inserted through the lateral through-opening in the sleeve by screwing it into the sleeve, which has the internal thread.

[0016] A particularly simple and secure fixation is possible if the sleeve has a first and a second lateral through-hole through which the flexible element is inserted. This allows the flexible element to pass completely through the sleeve and can be securely fixed in the sleeve using the screw element.

[0017] Further preferably, the flexible element on the floating ring extends out of the floating ring through a radial bore formed in the floating ring. The flexible element is secured in the floating ring by means of the first fixing device.

[0018] Particularly preferably, a blind hole running in the axial direction is formed in the floating ring, which is designed to receive the first fixing device and wherein the flexible element is fixed in the blind hole. Particularly preferably, the flexible element is guided out of the blind hole through the radial bore. The first fixing device is preferably also designed as a sleeve which has an internal thread and at least one lateral through-opening, preferably two lateral through-openings. The flexible element is guided through the one lateral through-opening or the two lateral through-openings and then, as described above, is fixed by clamping by a screw element, for example a grub screw, in the sleeve provided with the internal thread.A particularly compact design is possible if the flex element on the floating ring extends radially between a first and a second circumferentially extending spring element. The use of circumferentially extending spring elements allows the floating ring to be constructed in multiple parts, with the spring elements holding the multiple parts of the floating ring together. This, in particular, enables simplified assembly of the floating ring and the rotation-locking unit.

[0019] Further preferably, on the radial bore leading out of the floating ring, an opening of the radial bore is formed on the outer circumference of the floating ring such that the radial bore widens in a funnel shape. This prevents the flexible element from causing damage to the floating ring at a possible edge of the radial bore during radial and / or axial movements of the floating ring. The funnel-shaped widening allows for gentle application of the flexible element during movements of the floating ring. This significantly reduces the risk of damage to the floating ring due to the widening opening of the radial bore. The funnel-shaped opening is preferably very flat and, in particular, has an angle of < 45°.

[0020] The present invention is particularly advantageous when the floating ring is a carbon floating ring. Carbon floating rings are highly suitable as floating ring seals and have a very long service life. They also allow a floating ring seal to be provided in a simple and cost-effective split design, which facilitates assembly of the floating ring seal. This is particularly important since floating ring seals are often used to seal rotating components with large outer diameters, such as pump shafts or compressor shafts.

[0021] Preferably, the second fixing device, which fixes the flex element to the housing, is designed as a welded connection.

[0022] Particularly preferably, the floating ring seal comprises a plurality of floating rings arranged next to one another in series, each with a rotation locking unit according to the invention.

[0023] A preferred embodiment of the invention will be described in detail below with reference to the accompanying drawings. In the drawing:

[0024] Fig. 1 is a schematic sectional view of a floating ring seal according to a preferred embodiment of the invention,

[0025] Fig. 2 is a schematic, enlarged partial sectional view of the floating ring seal of

[0026] Fig. 1 , which shows a rotation locking unit in cross section, and Fig. 3 is a schematic, perspective partial sectional view of the floating ring seal of Fig. 1.

[0027] A floating ring seal 1 according to a preferred embodiment of the invention will be described in detail below with reference to Figs. 1 to 3.

[0028] The floating ring seal 1 is a carbon floating ring seal comprising a multi-part floating ring 2 composed of circumferential segments. The floating ring 2 is held together by a first spring element 11 and a second spring element 12, which extend circumferentially around the outer circumference of the floating ring 2.

[0029] The floating ring 2 has a radial sealing surface 20 on a radial inner side, which is designed to ensure sealing against a rotating shaft 3. During operation, the floating ring 2 must be prevented from rotating together with the rotating shaft 3. XX indicates an axial direction.

[0030] The floating ring 2 is arranged in a multi-part housing 4, with an annular gap 6 radially extending between the housing 4 and the floating ring 2. The annular gap 6 allows the floating ring seal to follow radial movements of the shaft that may occur during operation. This is indicated schematically in Fig. 1 by the double arrow A.

[0031] A sealing gap between the radial sealing surface 20 and the outer circumference of the shaft 3 should be as small as possible in order to prevent a large leakage from a product chamber 7 to an atmosphere 8.

[0032] For this purpose, the floating ring seal 1 comprises a rotation-locking unit 5, which is designed to prevent rotation of the floating ring when the shaft is rotating. The rotation-locking unit 5 thus acts as an anti-rotation device that prevents the shaft 3 and floating ring 2 from rotating together.

[0033] As can be seen in detail from Fig. 2, the rotation locking unit 5 comprises a rope-like flex element 50, a first fixing device 51 and a second fixing device 52.

[0034] The first and second fixing devices 51, 52 are constructed identically. The first fixing device 51 is configured to fix the flexible element 50 to the floating ring 2. The second fixing device 52 is configured to fix the flexible element 50 to the housing 4.

[0035] As can be seen from Figs. 1 and 2, the first and second fixing devices 51, 52 each comprise a sleeve 53 and a grub screw 54. The sleeve 53 has an internal thread 53a into which the grub screw 54, which has an external thread, is screwed. As can be seen in detail in Fig. 2, the flex element 50 is clamped and thus fixed by the screwed-in grub screw. The flex element 50 is thus fixed in the same way at both free ends by the first and second fixing devices 51, 52.

[0036] As can be seen in particular from Fig. 1, the movable, rope-like flex element 50 is arranged exclusively in the radial direction and runs through the intermediate space 6. As shown in Fig. 2, the rope-like flex element 50 has a loop 50a, the size of which can be freely selected depending on the application. This makes it possible for the rotation locking unit 5 to be easily adapted to different radial deflections of the shaft in different machines. For example, if it is known that the shaft 3 can perform large radial deflections during operation, the loop 50a of the flex element 50 can be selected to be large so that the floating ring 2 can follow corresponding deflections in the radial direction of the shaft.

[0037] To fix the flex element 50 to the floating ring 2, the first fixing device 51 has an axial blind hole 22 (see Fig. 1) and a radial hole 21. The radial hole 21 connects the blind hole 22 to an outer circumference of the floating ring 2 and leads into the intermediate space 6.

[0038] The radial bore 21 has a funnel-shaped opening 23 at the intermediate space 6. As shown in Fig. 3, the funnel-shaped opening 23 is very flat. This prevents damage to an edge at the opening 23 of the floating ring during operation, since the flexible element 50 can gently rest against the funnel-shaped opening 23 upon corresponding movements of the floating ring 2.

[0039] As can be seen from Fig. 2, the sleeve 53 has a first and a second through-opening 53b, 53c, which are arranged opposite one another, with the free end of the freely movable flex element 50 being guided through both through-openings 53b, 53c. This allows the free end of the flex element 50 to be securely clamped by the first fixing device 51. The sleeve 53 is formed in the same way on the second fixing device 52, with the free end also being guided through both through-openings 53b, 53c.

[0040] The second fixing device 52 is, as can be seen from Figs. 2 and 3, arranged partly in a first housing part 41 and partly in a second housing part 42. Fig. 3 shows a joint 43 between the first and second housing parts 41, 42. Thus, the recess 44 in the housing 4 has a first part 44a and a second part 44b, with one part being provided in each of the housing parts 41, 42. In order to be able to guide the flexible element 50 out of the recess 44, a groove 45 is provided in the second housing part 42 (cf. Fig. 2). The depth of the groove 45 corresponds to a diameter of the rope-like flexible element 50 and establishes the connection to the intermediate space 6.

[0041] The rope-like flex element 50 is preferably a wire rope with sufficient flexibility or a rope made of another tear-resistant material or a combination of materials.

[0042] If deflections of the shaft 3 occur during operation, both in the radial direction of the shaft and in the axial direction of the shaft, the floating ring seal 1 can easily follow such deflections in both directions. The rotation-locking unit 5 also prevents the floating ring 2 from rotating with the rotating shaft 3. The rope-like, flexibly movable flex element 50 ensures that any type of shaft movement can also be followed by the floating ring 2, since the rotation-locking unit is flexible in all directions thanks to the rope-like flex element 50.

[0043] Thus, according to the invention, a floating ring seal 1 can be provided which has a rotation-locking unit 5 that prevents the floating ring 2 from rotating with the shaft 3 while still allowing deflections of the shaft without damaging the floating ring seal 2. The rotation-locking unit 5 is very simple and cost-effective in design.

[0044] In the described embodiment, the housing 4 is constructed in two parts. However, it should be noted that the housing may also comprise more than two parts, for example, three or four parts. It should also be noted that the second fixing device 52 does not necessarily have to be arranged at a joint 43 between two housing parts, but can also be provided in corresponding recesses with radial bores at any location in the housing, wherein the arrangement of the second fixing device 52 is then configured as described for the first fixing device 51 on the floating ring 2.

[0045] Furthermore, the rotation-locking unit 5 is designed such that the length of the flexible element 50 can be freely selected. This allows for easy adaptation of the rotation-locking unit 5 to different types of floating ring seals 1.

[0046] It should also be noted that, in particular, the second fixing device 52 can also be designed as a welded joint with an appropriate choice of material.

[0047] 1 floating ring seal

[0048] 2 swimming rings

[0049] 3 Wave

[0050] 4 multi-part housing

[0051] 5 Rotation locking unit

[0052] 6 gap

[0053] 7 Product room

[0054] 8 Atmosphere

[0055] 11 first spring element

[0056] 12 second spring element

[0057] 20 radial sealing surface of the floating ring

[0058] 21 Radial bore

[0059] 22 axial blind hole

[0060] 23 funnel-shaped mouth

[0061] 41 first housing part

[0062] 42 second housing part

[0063] 43 Joint of the housing parts

[0064] 44 recess

[0065] 44a first part of the recess

[0066] 44b second part of the recess

[0067] 45 groove

[0068] 50 rope-like flex element

[0069] 50a loop

[0070] 51 first fixing device

[0071] 52 second fixing device

[0072] 53 sleeve

[0073] 53a internal thread

[0074] 53b Through opening

[0075] 53c Passage opening

[0076] 54 grub screw

[0077] A Deflection in radial direction

[0078] XX Axial direction

Claims

Claims 1. A floating ring seal, comprising: a floating ring (2) with a radial sealing surface (20), configured to seal against a rotating component (3), a multi-part housing (4) which accommodates the floating ring, wherein an annular intermediate space (6) is present between the housing and the floating ring (2), and a rotation-locking unit (5) configured to prevent rotation of the floating ring (2) with the rotating component (3), wherein the rotation-locking unit (5) has a flex element (50), a first fixing device (51) and a second fixing device (52), wherein the first fixing device (51) fixes the flex element to the floating ring (2) and the second fixing device (52) fixes the flex element to the housing (4), and wherein the flex element (50) is configured to enable axial and radial movements of the floating ring (2).

2. Floating ring seal according to claim 1, wherein the flex element (50) is a rope-like element made of a tear-resistant material.

3. Floating ring seal according to one of the preceding claims, wherein the flexible element (50) extends in the radial direction of the floating ring (2).

4. Floating ring seal according to one of the preceding claims, wherein the flexible element (50) forms at least one loop (50a) between the floating ring (2) and the housing (4).

5. Floating ring seal according to one of the preceding claims, wherein the second fixing device (52) is arranged at a joint (43) of a first housing part (41) and a second housing part (42) of the housing (4) between the housing parts.

6. Floating ring seal according to claim 5, wherein the second fixing device (52) is arranged in a recess (44) in the housing (4) and the recess is connected by means of a groove (45) to the intermediate space (6) between the housing (4) and the floating ring (2), wherein the flex element (50) is guided through the groove (45).

7. Floating ring seal according to one of the preceding claims, wherein the first and second fixing devices (51, 52) each comprise a sleeve (53) with an internal thread (51a) and at least one lateral through-opening (53b, 53c) and a screw element (54), wherein the flexible element is guided through the through-opening (53b, 53c) into the sleeve (53) and is fixed in the sleeve by means of the screw element (54).

8. Floating ring seal according to claim 7, wherein the sleeve (53) has a first through-opening (53b) and a second through-opening (53c), wherein the flex element (50) is guided through both through-openings (53b, 53c).

9. Floating ring seal according to one of the preceding claims, wherein the flexible element (50) on the floating ring (2) is led out of the floating ring through a radial bore (21).

10. Floating ring seal according to one of the preceding claims, wherein the floating ring (2) has an axial blind hole (22) in which the first fixing device (51) is arranged and fixes the flex element (50).

11. Floating ring seal according to one of the preceding claims, wherein the flexible element (50) is led out of the floating ring (2) radially between a first spring element (11) and a second spring element (12), which run in the circumferential direction of the floating ring.

12. Floating ring seal according to one of claims 9 to 11, wherein on a radially outer side of the radial bore (21) a widening mouth, in particular a funnel-shaped mouth, is formed through which the flex element (50) is led out of the floating ring.

13. Floating ring seal according to one of the preceding claims, wherein the flexible element (50) is a rope or a wire or a cord.

14. Floating ring seal according to one of the preceding claims, wherein the floating ring seal is a carbon floating ring seal.

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