Rotary kiln seal system with wear protection assembly

Abstract

The invention relates to a rotary kiln seal system with a wear protection assembly. The rotary kiln seal system comprises a seal disc which is designed to be secured to the exterior of a rotary tube. The seal disc has a first product side in a first axial direction and an atmosphere side in a second axial direction. The rotary kiln seal system additionally comprises an annular housing which is arranged on the seal disc. A first seal ring is arranged on the housing coaxially to the central axis of the seal disc, and the first seal ring is designed to contact the seal disc. The rotary kiln seal system additionally comprises a wear protection assembly which is arranged on the housing. The wear protection assembly is designed to limit the force of the seal disc on the first seal ring. The wear protection assembly thus functions as a force limiter and is designed in particular to limit forces acting on the first seal ring in the axial direction.

Description

[0001] Rotary kiln sealing system with wear protection arrangement

[0002] Description

[0003] The invention relates to a rotary kiln sealing system with wear protection arrangement.

[0004] Rotary kilns are rotating cylindrical kilns for continuous processes in process engineering and are used, for example, in cement production. A rotating rotary tube, within which high temperatures are present, must be sealed to a stationary housing of the rotary kiln. Rotary kilns can have a diameter of several meters and reach internal temperatures of over 1000°C. The processes in the rotary kiln often take place in the absence of oxygen. To increase efficiency or enable new processes, industry is placing increasing demands on the temperature resistance and sealing properties of the rotary kiln.

[0005] The object of the invention is to provide an improved rotary kiln sealing system with reduced wear and tear while being simple and cost-effective to manufacture.

[0006] This problem is solved by a rotary kiln sealing system having the features of claim 1.

[0007] The rotary kiln sealing system according to the invention with the features of claim 1 comprises a sealing disc which is designed to be fastened to an outer side of a rotary kiln. The sealing disc has a product side in a first axial direction and an atmosphere side in a second axial direction. Furthermore, the rotary kiln sealing system comprises an annular housing which is arranged on the sealing disc. A first sealing ring is arranged on the housing coaxially to a central axis of the sealing disc. The first sealing ring is designed to contact the sealing disc. Furthermore, the rotary kiln sealing system comprises a wear protection arrangement which is arranged on the housing. The wear protection arrangement is designed to limit a force from the sealing disc to the first sealing ring.The wear protection arrangement thus acts as a force limiter and is specifically designed to limit axial forces acting on the first sealing ring. Consequently, wear on the first sealing ring can be reduced, which can improve its service life.

[0008] The product side borders the product area of ​​the rotary kiln, while the atmosphere side borders the environment.

[0009] The first sealing ring is preferably a packing sealing ring made of a braided fabric which is impregnated with a lubricant.

[0010] The subclaims show further preferred developments of the invention.

[0011] The wear protection arrangement preferably comprises a first slide ring which is arranged coaxially to the central axis on the housing and is designed to contact the sealing disc in order to limit the force from the sealing disc on the first sealing ring. During operation, the first slide ring preferably slides on the sealing disc such that a sealing gap forms between the first slide ring and the sealing disc, whereby the slide ring does not contact the sealing disc. During start-up of the rotary kiln or due to axial forces which are transmitted from the rotary kiln via the sealing disc to the rotary kiln sealing system, contact and friction can occur between the slide ring and the sealing disc. The first slide ring can absorb axial forces from the sealing disc and prevents mass transfer between the product side and the atmosphere side. Slide rings have a higher hardness than sealing rings and can absorb higher axial forces than sealing rings.At the same time, the sliding rings continue to exhibit low sliding friction values ​​when in contact with the sealing disc. Furthermore, the sliding rings are robust and easy to maintain during operation. Thus, the use of the first sliding ring in the rotary kiln sealing system can reduce wear on the first sealing ring, thereby improving the service life of the rotary kiln sealing system.

[0012] The rotary kiln sealing system further preferably comprises a second sealing ring arranged coaxially with the central axis. The first seal ring is arranged between the first seal ring and the second seal ring. By being arranged between a first seal ring and a second seal ring, the first seal ring is protected from particles that may enter from the product side or the atmosphere side between the first seal ring and the sealing disk and cause abrasive wear there.

[0013] The first sealing ring, the second sealing ring, and the first sliding ring preferably lie on a common radial plane, which is aligned orthogonally to the central axis. The arrangement of the first sealing ring, the second sealing ring, and the first sliding ring arranged between them on a common radial plane can reduce the leverage forces acting on the sealing elements during tilting movements of the sealing disc. Further preferably, the first sealing ring is arranged on the product side of the sealing disc.

[0014] Particularly preferably, the first sliding ring is positioned centrally between the first sealing ring and the second sealing ring. The central arrangement of the first sliding ring ensures an even distribution of the sealing force across the sealing surface between the sealing rings and the sealing disc. This even distribution results in even wear on the sealing rings. Thus, the worn sealing rings can be replaced simultaneously, simplifying maintenance of the rotary kiln sealing system.

[0015] According to a further preferred embodiment of the invention, the rotary kiln sealing system comprises a third sealing ring, a fourth sealing ring, and a second sliding ring, wherein the third sealing ring, the fourth sealing ring, and the second sliding ring are aligned coaxially with the central axis. The second sliding ring is preferably arranged between the third sealing ring and the fourth sealing ring. The additional third sealing ring, fourth sealing ring, and second sliding ring distribute the force from the sealing disc across multiple components, thus reducing wear on the individual components.

[0016] More preferably, the second seal ring is positioned centrally between the third sealing ring and the fourth sealing ring. The central arrangement of the second seal ring ensures an even distribution of the sealing force across the sealing surface between the sealing rings and the sealing disc. This even distribution results in even wear on the sealing rings. Thus, the worn sealing rings can be replaced simultaneously, simplifying maintenance of the rotary kiln sealing system.

[0017] Preferably, the third sealing ring, the fourth sealing ring, and the second sliding ring are arranged on the atmosphere side of the sealing disc. By arranging the first sealing ring, the second sealing ring, and the first sliding ring on the atmosphere side and the third sealing ring, the fourth sealing ring, and the second sliding ring on the product side, the rotary kiln sealing system can reliably seal during axial movements of the rotary tube and the sealing disc both toward the product side and toward the atmosphere side. The sliding rings distributed on both sides limit the forces on the sealing rings and thus reduce wear on the rotary kiln sealing system. Furthermore, the arrangement of sliding rings and sealing rings on both sides enables a compact design of the rotary kiln sealing system.

[0018] The first sealing ring and the third sealing ring preferably have the same first radius. More preferably, the second sealing ring and the fourth sealing ring have the same second radius. Particularly preferably, the first sliding ring and the second sliding ring have the same third radius. The radii relate to the center radius of the sealing rings and / or sliding rings. The inner radii and / or outer radii of the respective sealing rings and / or sliding rings are also preferably the same. Because the opposing sealing rings and sliding rings have the same radii, they can be interchanged if they show different levels of wear, which extends the service life of the rotary kiln sealing system. The reduced number of sliding rings and sealing rings of different sizes further reduces production costs and increases the availability of spare parts.

[0019] The wear protection arrangement preferably comprises a connection system configured to introduce a fluid into a space between the housing and the sealing disc. The fluid can be a gas and / or a liquid and, for example, improve the sliding properties between the sealing disc and the sealing ring and / or the sliding ring. The fluid can also be a cooling fluid, whereby the introduction of the cooling fluid can, for example, reduce the heating of the sealing rings and sliding rings and further improve the wear properties of the rotary kiln sealing system.

[0020] Further details, advantages, and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the drawings. It shows:

[0021] Fig. 1 is a schematic representation of a rotary kiln sealing system according to a preferred embodiment, and

[0022] Fig. 2 is a schematic representation of a circumferentially segmented first sliding ring according to the preferred embodiment.

[0023] A rotary kiln sealing system 1 according to a preferred embodiment of the invention is described in detail below with reference to Figures 1 and 2.

[0024] Figure 1 shows a rotary kiln sealing system 1 with a wear protection arrangement 30. The rotary kiln sealing system 1 has a sealing disc 20 which is fastened to a rotary tube 21 via a fastening flange 22.

[0025] The rotary kiln sealing system 1 seals a product side 23 of a rotary kiln to an atmosphere side 24, wherein the product side 23 is located in a first axial direction R1 of the sealing disc 20 and the atmosphere side 24 is located in an opposite second axial direction R2 of the sealing disc 20.

[0026] The sealing disc 20 is aligned coaxially with a central axis XX of the rotary tube 21. Preferably, the sealing disc 20 is made of a metal and has a constant thickness.

[0027] An annular housing 10 is arranged around the sealing disc 20 coaxially to a central axis XX of the rotary tube 21. The housing 10 has a U-shaped cross-section that opens radially inward. The sealing disc 20 is arranged floatingly in the opening of the U-shaped cross-section, so that the sealing disc 20 is configured to rotate within the housing 10. The housing 10 is shown as a single piece, but can also be composed of multiple components.

[0028] The housing 10 is connected to a housing component 26 of the rotary kiln on the product side 23 via a compensator 25 to compensate for axial and radial movements of the rotary kiln 21, for example, due to thermal expansion. The compensator 25 is preferably a fabric compensator.

[0029] The mounting flange 22 is preferably welded to the rotary tube 21. Further preferably, the mounting flange 22 has bores for detachably connecting the sealing disc 20 to the mounting flange 22 via a screw connection, so that the sealing disc 20 can be easily replaced when worn.

[0030] A first sealing ring 31, a second sealing ring 32, and a circumferentially segmented first sliding ring 11 are arranged within recesses of the housing 10 on the product side 23 of the sealing disc 20. The first sealing ring 31 is arranged radially within the second sealing ring 32. Furthermore, the first sliding ring 11 is arranged radially centrally between the first sealing ring 31 and the second sealing ring 32.

[0031] The first sealing ring 31, the second sealing ring 32, and the first sliding ring 11 lie on a common radial plane, which is aligned orthogonally to the central axis XX, and are configured to contact the sealing disc 20. Thus, a radial first chamber 41 is formed between the first sealing ring 31, the housing 10, the second sealing ring 32, and the sealing disc 20, which is sealed to the outside by the first sealing ring 31 and the second sealing ring 32. The segmented first sliding ring 11 is arranged within the first chamber 41.

[0032] On the atmosphere side 24 of the sealing disc 20, a third sealing ring 33, a fourth sealing ring 34, and a second sliding ring 12 are arranged in recesses in the housing 10. The fourth sealing ring 34 is arranged radially inside the third sealing ring 33. Furthermore, the second sliding ring 12 is arranged radially between the third sealing ring 33 and the fourth sealing ring 34.

[0033] The third sealing ring 33, the fourth sealing ring 34, and the second sliding ring 12 lie on a further common radial plane, which is aligned orthogonally to the central axis XX, and are configured to contact the sealing disk 20 on the atmosphere side 24. Thus, a radial second chamber 42 is formed between the third sealing ring 33, the housing 10, the fourth sealing ring 34, and the sealing disk 20, which is sealed to the outside by the third sealing ring 33 and the fourth sealing ring 34. The segmented second sliding ring 12 is arranged within the second chamber 42. The first sealing ring 31 and the fourth sealing ring 34 have an identical first radius r1, which is a mean radius of the first sealing ring 31 and the fourth sealing ring 34. The first sliding ring 11 and the second sliding ring 12 have an equal third radius r3 and the second sealing ring 32 and the third sealing ring 33 have an equal second radius r2.The second radius r2 and the third radius r3 are also average radii of the second sealing ring 32 and the third sealing ring 33 as well as of the first sliding ring 11 and the second sliding ring 12. A first distance L1 in the radial direction between the third sealing ring 33 and the second sliding ring 12 is the same as a second distance L2 in the radial direction between the second sliding ring 12 and the fourth sealing ring 34. Thus, the second sliding ring 12 is arranged centrally between the third sealing ring 33 and the fourth sealing ring 34. The first sliding ring 11 is thus also arranged centrally between the first sealing ring 31 and the second sealing ring 32.

[0034] Furthermore, the second sealing ring 32, the third sealing ring 33, the housing 10 and the sealing disc 20 form an annular third chamber 43 at the radially outer end of the sealing disc 20. Thus, the product from the product side 23 must pass through the first sealing ring 31, the first chamber 41 with the first sliding ring 11, the second sealing ring 32, the third chamber 43, the third sealing ring 33, the second chamber 42 with the second sliding ring 12 and the fourth sealing ring 34 in order to reach the atmosphere side 24.

[0035] The housing 10 has a first connection system 14 on the product side 23, which is placed circumferentially between two segments 11a, 11b of the first sliding ring 11 and is configured to convey a fluid into or out of the first chamber 41.

[0036] On the opposite side of the sealing disc 20, a second connection system 15 is circumferentially positioned between two segments of the second sliding ring 12 in the housing 10. The second connection system 15 enables a fluid to be conveyed into or out of the second chamber 42 and a fluid to be conveyed into or out of the third chamber 43.

[0037] Peripherally, one connection 17 or a plurality of connections 17 can be placed in the housing 10 per connection system 14, 15, 16. A plurality of connections 17 per connection system 14, 15, 16 enables a fluid circuit in a chamber 41, 42, 43, wherein the fluid is introduced through at least one connection 17 and sucked out through at least one other connection 17 in the respective chamber 41, 42, 43.

[0038] The first connection system 14 is connected to a first fluid system F1, which is configured to supply the first chamber 41 with an individual fluid having an individual pressure and / or individual temperature. The second connection system 15 is connected to a second fluid system F2, which is configured to supply the second chamber 42 with an individual fluid having an individual pressure and / or individual temperature. Furthermore, the third connection system 16 is connected to a third fluid system F3, which is configured to supply the third chamber 43 with an individual fluid having an individual pressure and / or individual temperature.

[0039] The fluid systems F1, F2, F3 are connected to a control unit S, which is designed to control the fluid systems F1, F2, F3 in such a way that the correct amount of fluid with the correct chemical and physical properties is conveyed into or out of the chambers 41, 42, 43 in order to best reduce the wear of the rotary kiln sealing system 1 and to increase the sealing properties.

[0040] Figure 2 schematically shows the circumferentially segmented first sliding ring 11 according to the preferred embodiment. The first sliding ring 11 is annular and divided into four equally sized segments, namely a first segment 11a, a second segment 11b, a third segment 11c, and a fourth segment 11d.

[0041] The first connection system 14 comprises four connections 17, which are positioned circumferentially between the segments 11a, 11b, 11c, 11d and are configured to convey a fluid into or out of the first chamber 41 and the sealing gap of the first sliding ring 11. In the housing 10, the first sliding ring 11 is arranged substantially coaxially with the central axis XX of the rotary tube 21, wherein the rotary tube 21 is arranged in a radially floating manner in the housing 10 via the sealing disk 20.

[0042] Thus, connections 17 are arranged at all free intermediate areas 18 located in the circumferential direction of the sliding ring 11.

[0043] The first connection system 14 is connected to the first fluid system F1, which is controlled by the control unit S in order to achieve a defined pressure and / or a defined temperature and / or a defined fluid in the first chamber 41.

[0044] In addition to the above written description of the invention, reference is hereby explicitly made to the drawings in the figures for its supplementary disclosure. List of reference symbols

[0045] I Rotary kiln sealing system

[0046] 10 housings

[0047] II First sliding ring

[0048] 11a First Segment

[0049] 11 b Second segment

[0050] 11c Third Segment

[0051] 11d Fourth Segment

[0052] 12 Second sliding ring

[0053] 14 First connection system

[0054] 15 Second connection system

[0055] 16 Third connection system

[0056] 17 Connection

[0057] 18 Intermediate area

[0058] 20 sealing washer

[0059] 21 rotary kiln

[0060] 22 Mounting flange

[0061] 23 Product page

[0062] 24 Atmosphere page

[0063] 25 Compensator

[0064] 26 Housing component

[0065] 30 Wear protection arrangement

[0066] 31 First sealing ring

[0067] 32 Second sealing ring

[0068] 33 Third sealing ring

[0069] 34 Fourth sealing ring

[0070] 41 First Chamber

[0071] 42 Second Chamber

[0072] 43 Third Chamber

[0073] F1 First fluid system

[0074] F2 Second fluid system

[0075] F3 Third fluid system

[0076] L1 First distance

[0077] L2 Second distance r1 First radius r2 Second radius r3 Third radius R1 First axial direction

[0078] R2 Second axial direction

[0079] S control unit

[0080] XX Central axis

Claims

Claims 1. Rotary kiln sealing system, comprising . a sealing disc (20) which is designed to be fastened to an outer side of a rotary tube (21), wherein the sealing disc (20) has a product side (23) in a first axial direction (R1) and an atmosphere side (24) in a second axial direction (R2), . an annular housing (10) which is arranged on the sealing disc (20), . a first sealing ring (31) which is arranged coaxially to a central axis (XX) of the sealing disc (20) on the housing (10) and is designed to contact the sealing disc (20), and . a wear protection arrangement (30) which is arranged on the housing (10), . wherein the wear protection arrangement (30) is arranged to limit a force from the sealing disc (20) to the first sealing ring (31).

2. Rotary kiln sealing system according to claim 1, wherein the wear protection arrangement (30) comprises a first sliding ring (11) which is arranged coaxially to the central axis (XX) on the housing (10) and is configured to contact the sealing disc (20) in order to limit the force from the sealing disc (20) on the first sealing ring (31).

3. Rotary kiln sealing system according to claim 2, wherein the rotary kiln sealing system (1) comprises a second sealing ring (32) which is arranged coaxially to the central axis (XX), wherein the first sliding ring (11) is arranged between the first sealing ring (31) and the second sealing ring (32).

4. Rotary kiln sealing system according to claim 3, wherein the first sealing ring (31), the second sealing ring (32) and the first sliding ring (11) lie on a common radial plane which is aligned orthogonal to the central axis (XX).

5. Rotary kiln sealing system according to claim 3 or 4, wherein the first sealing ring (31) is arranged on the product side (23) of the sealing disc (20).

6. Rotary kiln sealing system according to one of claims 3 to 5, wherein the first sliding ring (11) is placed centrally between the first sealing ring (31) and the second sealing ring (32).

7. Rotary kiln sealing system according to claims 2 to 6, wherein the rotary kiln sealing system (1) comprises a third sealing ring (33), a fourth sealing ring (34) and a second sliding ring (12), wherein the third sealing ring (33), the fourth sealing ring (34) and the second sliding ring (12) are aligned coaxially to the central axis (XX), wherein the second sliding ring (12) is arranged between the third sealing ring (33) and the fourth sealing ring (34).

8. Rotary kiln sealing system according to claim 7, wherein the second sliding ring (12) is placed centrally between the third sealing ring (33) and fourth sealing ring (34).

9. Rotary kiln sealing system according to one of claims 7 or 8, wherein the third sealing ring (33), the fourth sealing ring (34) and the second sliding ring (12) are arranged on the atmosphere side (24) of the sealing disc (20).

10. Rotary kiln sealing system according to claim 9, wherein the first sealing ring (31) and the third sealing ring (33) have an identical first radius (r1) and / or wherein the second sealing ring (32) and the fourth sealing ring (34) have an identical second radius (r2) and / or wherein the first sliding ring (11) and the second sliding ring (12) have an identical third radius (r3).

11. Rotary kiln sealing system according to one of the preceding claims, wherein the wear protection arrangement (30) comprises a connection system (14) which is designed to introduce a fluid into a space between the housing (10) and the sealing disc (20).

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