Rotary tube furnace sealing system with compensating arrangement

Abstract

The invention relates to a rotary kiln sealing system with a compensating device. The rotary kiln sealing system comprises a sealing disc designed to be attached to the 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. The product side borders the product area of ​​the rotary kiln, while the atmosphere side borders the environment. Furthermore, the rotary kiln sealing system comprises an annular housing arranged on the sealing disc. A first sliding ring is arranged on the housing, coaxial with a central axis of the sealing disc, and is designed to contact the sealing disc. The rotary kiln sealing system also includes a compensating device located between the housing and the first sliding ring.The compensating arrangement is designed to change the position of the first sliding ring in order to compensate for wear of the first sliding ring.

Description

[0001] The invention relates to a rotary kiln sealing system with a compensation arrangement.

[0002] 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 exist, 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 demands are increasing regarding the temperature resistance and sealing properties of the rotary kiln.

[0003] The object of the invention is to provide an improved rotary kiln sealing system with a long service life and simple and cost-effective manufacture.

[0004] This problem is solved by a rotary kiln sealing system having the features of claim 1.

[0005] 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 slide ring is arranged on the housing, which is arranged coaxially to a central axis of the sealing disc on the housing and is designed to contact the sealing disc. Furthermore, the rotary kiln sealing system comprises a compensating arrangement which is arranged between the housing and the first slide ring. The compensating arrangement is designed to change the position of the first slide ring in order to compensate for wear on the first slide ring.

[0006] The product side borders the product area of ​​the rotary kiln, while the atmosphere side borders the environment. During operation, the seal ring slides preferentially on the sealing disc, so that a sealing gap forms between the seal ring and the sealing disc, whereby the seal ring does not contact the sealing disc. During start-up of the rotary kiln or due to axial forces transmitted from the rotary kiln via the sealing disc to the seal ring, contact and friction can occur between the seal ring and the sealing disc. The first seal ring can absorb axial forces from the sealing disc and prevents mass transfer between the product side and the atmosphere side. Due to friction between the first seal ring and the sealing disc, the seal ring can wear out and become thinner. Thus, the distance between the sealing disc and the first seal ring increases with increasing wear.If the distance between the seal ring and the sealing disc becomes too large, the seal ring's ability to absorb forces from the sealing disc and seal the product side to the atmosphere side decreases. The compensating arrangement makes it possible to compensate for the wear-related increase in the distance between the seal ring and the sealing disc.

[0007] The subclaims show further preferred developments of the invention.

[0008] The rotary kiln sealing system preferably comprises a second sliding ring, which is arranged coaxially with the central axis on the housing and is configured to contact the sealing disc. The compensating arrangement is arranged between the housing and the second sliding ring and is configured to change the position of the second sliding ring to compensate for wear on the second sliding ring. Thus, different wear on the first sliding ring and the second sliding ring can be compensated for by the compensating arrangement.

[0009] Further preferably, the first seal ring is arranged on the product side of the sealing disc, and the second seal ring is arranged on the atmosphere side of the sealing disc. This enables a compact rotary kiln sealing system.

[0010] The compensation arrangement preferably comprises a plate-shaped compensation element arranged in the direction of the central axis between the housing and the rear side of the first sliding ring and / or between the housing and the rear side of the second sliding ring. A plate-shaped compensation element is understood to be a thin, flat, and planar compensation element with a consistent thickness. Plate-shaped compensation elements can be manufactured easily and cost-effectively and enable simple wear compensation.

[0011] Further preferably, at least two plate-shaped compensating elements are arranged one above the other in the direction of the central axis. By arranging several plate-shaped compensating elements one above the other, wear on the sliding rings can be compensated for in small increments as needed.

[0012] Preferably, a varying number of plate-shaped compensation elements are arranged one above the other in the direction of the center axis on the circumference between the first seal ring and the housing and / or the second seal ring and the housing. The varying number of plate-shaped compensation elements allows for targeted compensation of wear on the first seal ring and / or the second seal ring. Arranging a varying number of plate-shaped compensation elements one above the other enables targeted adjustment of the seal rings to the sealing disc. For example, an angular misalignment between the sealing disc and the housing and the seal rings arranged thereon can be compensated for by the plate-shaped compensation elements.

[0013] The plate-shaped compensating element is preferably ring-shaped. The plate-shaped compensating element is preferably aligned coaxially with the center axis. This allows the plate-shaped compensating element to quickly compensate for wear on the sliding rings and, due to its rotational symmetry, does not require complex alignment.

[0014] Further preferably, the plate-shaped compensating element forms one, preferably several, ring segments segmented in the radial direction. Ring segments enable the compensation of an angular misalignment between the sliding ring and the sealing disc.

[0015] According to a further preferred embodiment of the invention, the cross-section of the plate-shaped compensating element perpendicular to the central axis is identical to the cross-section of the first sliding ring and / or the cross-section of the second sliding ring perpendicular to the central axis. Thus, the first and / or second sliding ring and the plate-shaped compensating element have the same profile in the axial direction. This enables direct force transmission from the housing, via the plate-shaped compensating elements, to the rear side of the sliding ring. Furthermore, the plate-shaped compensating element thus contains no superfluous material.

[0016] The plate-shaped compensation element is preferably made of sheet metal. Sheet metal is available in a wide variety of thicknesses for a wide range of metals, allowing for simple and cost-effective manufacturing of the plate-shaped compensation elements.

[0017] 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: Fig. 1 a schematic representation of a rotary kiln sealing system according to a preferred embodiment, Fig. 2 a schematic representation of a circumferentially segmented first sliding ring according to the preferred embodiment, and Fig. 3 a schematic detailed view of a compensation arrangement according to the preferred embodiment.

[0018] The following is based on the Fig. 1 to 3 a rotary kiln sealing system 1 according to a preferred embodiment of the invention is described in detail.

[0019] Fig. 1 shows a rotary kiln sealing system 1 with a sealing disc 20, which is attached to a rotary tube 21 via a mounting flange 22.

[0020] 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.

[0021] The sealing disc 20 is aligned coaxially with a central axis X - X of the rotary tube 21. Preferably, the sealing disc 20 is made of a metal and has a constant thickness.

[0022] An annular housing 10 is arranged around the sealing disc 20. The housing 10 has a U-shaped cross-section, which opens radially inward and is aligned substantially coaxially with the central axis X-X of the rotary tube 21. 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.

[0023] Furthermore, the rotary kiln sealing system 1 has a compensation arrangement 30, which is arranged between the housing 10 and a first sliding ring 11, as well as between the housing 10 and a second sliding ring 12.

[0024] 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.

[0025] 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.

[0026] A first sealing ring 31, a second sealing ring 32, and the circumferentially segmented first sliding ring 11 are arranged within recesses in the housing 10 on the product side 23 of the sealing disc 20. The sealing rings are preferably packing sealing rings made of a braided fabric. Furthermore, the sliding rings have a higher hardness than the sealing rings. The first sealing ring 31 is arranged radially inside the second sealing ring 32. Furthermore, the first sliding ring 11 is arranged radially between the first sealing ring 31 and the second sealing ring 32. The first sealing ring 31, the second sealing ring 32, and the first sliding ring 11 are designed 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 off from 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.

[0027] On the atmosphere side 24 of the sealing disc 20, a third sealing ring 33, a fourth sealing ring 34, and the second slide 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 slide ring 12 is arranged radially between the third sealing ring 33 and the fourth sealing ring 34. The third sealing ring 33, the fourth sealing ring 34, and the second slide ring 12 are designed to contact the sealing disc 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 disc 20, which is sealed to the outside by the third sealing ring 33 and the fourth sealing ring 34. The segmented second slide ring 12 is arranged inside the second chamber 42.

[0028] The compensation arrangement 30 comprises one or more plate-shaped compensation elements 35. In the direction of the central axis X - X, plate-shaped compensation elements 35 are arranged between the housing 10 and the first sliding ring 11, as well as between the housing 10 and the second sliding ring 12, which in an enlarged view of the preferred embodiment in Fig. 3 are shown.

[0029] 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.

[0030] The housing 10 has a first connection system 14 on the product side 23, which is placed circumferentially between two segments of the plate-shaped compensating element 35 and the first sliding ring 11 and is designed to convey a fluid into or out of the first chamber 41.

[0031] 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.

[0032] On the axially outer side of the housing 10, a third connection system 16 is attached, which is designed to convey a fluid into or out of the third chamber 43.

[0033] On the periphery, 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.

[0034] 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.

[0035] The fluid systems F1, F2, F3 are connected to a control unit S, which is configured 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 enable optimal sealing of the rotary kiln by the rotary kiln sealing system 1.

[0036] Fig. Figure 2 schematically shows annular segments of plate-shaped compensating elements 35. The plate-shaped compensating elements are similar in profile to the circumferentially segmented first sliding ring 11 according to the preferred embodiment. The plate-shaped compensating elements 35 are annular and divided into four equally sized segments.

[0037] The first connection system 14 comprises four connections 17, which are positioned circumferentially in an intermediate region 18 between the segments of the plate-shaped compensating elements 35 and the first sliding ring 11 adjacent perpendicular to the image plane. The first connection system is 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 ring segments of the plate-shaped compensating elements 35 are arranged substantially coaxially with the central axis X-X of the rotary tube 21, with the rotary tube 21 being arranged in a radially floating manner in the housing 10 via the sealing disk 20.

[0038] 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.

[0039] Fig. 3 shows a schematic detailed view of the rotary kiln sealing system 1 in the area of ​​the first sealing ring 31 and the first sliding ring 11.

[0040] In the direction of the central axis X-X, two plate-shaped compensating elements 35 are arranged one above the other between the first sliding ring 11 and the housing 10. Thus, the plate-shaped compensating elements 35 are arranged on a rear side 13 of the first sliding ring 11. The plate-shaped compensating elements 35 both have the same thickness and allow the position of the first sliding ring 11 to be changed in the direction of the sealing disc 20.

[0041] Without the plate-shaped compensating elements 35, the first sliding ring 11 would be arranged completely within the recess in the housing 10 and would no longer be able to contact the sealing disc 20 due to wear. Thus, the first sliding ring 11 would have Fig. 3 without plate-shaped compensation elements 35 must already be replaced.

[0042] In addition to the above written description of the invention, reference is hereby explicitly made to the graphic representation of the invention in the figures for its supplementary disclosure. List of reference symbols 1 rotary kiln sealing system 10 housings 11 First sliding ring 12 Second sliding ring 13 Back of the sliding ring 14 First connection system 15 Second connection system 16 Third connection system 17 Connection 18 Intermediate area 20 sealing washer 21 rotary kiln 22 Mounting flange 23 Product page 24 Atmosphere page 25 Compensator 26 Housing component 30 Compensation order 31 First sealing ring 32 Second sealing ring 33 Third sealing ring 34 Fourth sealing ring 35 Plate-shaped compensation element 41 First Chamber 42 Second Chamber 43 Third Chamber F1 First fluid system F2 Second fluid system F3 Third fluid system R1 First axial direction R2 Second axial direction S control unit X - X center axis

Claims

[1] Rotary kiln sealing system (1), 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 sliding ring (11) which is arranged coaxially to a central axis (X - X) of the sealing disc (20) on the housing (10) and is designed to contact the sealing disc (20), and • a compensating arrangement (30) which is arranged between the housing (10) and the first sliding ring (11), • wherein the compensation arrangement (30) is configured to change the position of the first sliding ring (11) in order to compensate for wear of the first sliding ring (11). [2] Rotary kiln sealing system (1) according to claim 1, comprising a second sliding ring (12) which is arranged coaxially to the central axis (X - X) on the housing (10) and is designed to contact the sealing disc (20), wherein the compensation arrangement (30) is arranged between the housing (10) and the second sliding ring (12) and is designed to change the position of the second sliding ring (12) in order to compensate for wear of the second sliding ring (12). [3] Rotary kiln sealing system (1) according to claim 2, wherein the first sliding ring (21) is arranged on the product side (23) of the sealing disc (20) and wherein the second sliding ring (12) is arranged on the atmosphere side (24) of the sealing disc (20). [4] Rotary kiln sealing system (1) according to one of the preceding claims, wherein the compensating arrangement (30) comprises a plate-shaped compensating element (35) which is arranged in the direction of the central axis (X - X) between the housing (10) and the rear side (13) of the first sliding ring (11) and / or the housing (10) and the rear side (13) of the second sliding ring (12). [5] Rotary kiln sealing system (1) according to claim 4, wherein at least two plate-shaped compensating elements (35) are arranged one above the other in the direction of the central axis (X - X). [6] Rotary kiln sealing system (1) according to claim 4 or 5, wherein a different number of plate-shaped compensating elements (35) are arranged one above the other in the direction of the central axis (X - X) on the circumference between the first sliding ring (11) and the housing (10) and / or the second sliding ring (12) and the housing (10). [7] Rotary kiln sealing system (1) according to one of claims 4 to 6, wherein the plate-shaped compensating element (35) is annular. [8] Rotary kiln sealing system (1) according to claim 7, wherein the plate-shaped compensating element (35) forms a ring segment. [9] Rotary kiln sealing system (1) according to one of claims 4 to 8, wherein the cross section of the plate-shaped compensating element (35) perpendicular to the central axis (X - X) is equal to the cross section of the first sliding ring (11) and / or the cross section of the second sliding ring (12) perpendicular to the central axis (X - X). [10] Rotary kiln sealing system (1) according to one of claims 4 to 10, wherein the plate-shaped compensating element (35) is made of a metal sheet.

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