Sealing system for sealing between a rotating component and a stationary component

Abstract

Sealing system for sealing between a rotating component (2) and a stationary component (3), comprising an annular seal housing (10) with a radially inwardly open U-shaped cross-section and a seal carrier (20) on which a first sealing ring (21), a second sealing ring (22), a third sealing ring (23) and a fourth sealing ring (24) are arranged, wherein the seal carrier (20) is arranged radially movable in the U-shaped cross-section of the seal housing (10), wherein a barrier chamber (4) is formed radially between the seal housing (10) and the seal carrier (20), wherein the seal housing (10) is designed to be fastened to the stationary component (3), wherein the first sealing ring (21) is designed to seal with a first contact surface (21a) axially against a first sealing surface (11) of the seal housing (10), wherein the second sealing ring (22) is designed,to seal axially with a second contact surface (22a) against a second sealing surface (12) of the seal housing (10), and wherein the third sealing ring (23) and the fourth sealing ring (24) are arranged to seal radially with a third contact surface (23a) and fourth contact surface (24a) against the rotating component (2).

Description

[0001] The invention relates to a sealing system for sealing a process side against an atmosphere side and to a ball mill with the sealing system, which seals a ring motor in the ball mill against a grinding chamber of a drum.

[0002] Large rotating drums, such as those found in ball mills or rotary kilns, can move axially and radially during operation. These movements should be absorbed by a sealing system mounted on the drum to reliably seal the process side of the drum from the atmospheric side. In the prior art, compensators are typically used as axial compensation elements. These are limited in terms of operating temperature, especially with moist, condensing gases, as well as in terms of axial movement, radial deflection, and thermal expansion. Simple lip seals are usually used for sealing, which are insufficiently able to accommodate radial and axial movement and lack sufficient wear resistance. Other sealing systems for rotary kilns are known, for example, from EP 1 445 566 A1, DE 10 27 024 A, DE 11 2013 004 040 T5, and DE 10 2018 100 166 B3.

[0003] The object of the invention is to provide a sealing system for very large diameters which can reliably seal a rotating component against a stationary component while being simple and cost-effective to manufacture and can thereby absorb radial and axial movements of the rotating component.

[0004] This object is achieved by the sealing system according to the invention with the features of claim 1. The sealing system for sealing between a rotating component and a stationary component has an annular seal housing with a radially inwardly open U-shaped cross-section and a seal carrier in which a first sealing ring, a second sealing ring, a third sealing ring, and a fourth sealing ring are arranged. The seal carrier is arranged radially movable in the U-shaped cross-section of the seal housing, wherein a barrier chamber is formed radially between the seal housing and the seal carrier. The seal housing is designed to be fastened to the stationary component.The first sealing ring can seal axially against a first sealing surface of the seal housing at a first contact surface and the second sealing ring can seal axially against a second sealing surface of the seal housing at a second contact surface. The third sealing ring and the fourth sealing ring can seal radially against the rotating component at a third contact surface and a fourth contact surface. The floating arrangement of the seal carrier within the seal housing can reliably absorb radial movements of the rotating component. The radial contact of the third sealing ring and the fourth sealing ring with the rotating component can enable the absorption of axial displacements of the rotating component, in particular if the rotating component is cylindrical in the region of the third sealing ring and the fourth sealing ring.The sealing system is particularly designed to seal a process side from an atmosphere side for very large diameters in the range of several meters. The sealing system can reliably seal the rotating component from the stationary component, even in a stationary state. The sealing system preferably has a torque driver, in particular with radial centering, to prevent rotational movements of the seal carrier.

[0005] The subclaims show preferred developments of the invention.

[0006] Preferably, the first, second, third, and / or fourth sealing ring is a packing seal, in particular a stuffing box packing, in particular with a rectangular cross-section, made of a fiber material, in particular of a braided fiber material. Packing seals can have good sealing properties with high abrasion resistance. Furthermore, packing seals can be flexibly adapted to large diameters to be sealed. The packing seal can preferably be made of a continuous aramid fiber or of expanded graphite. More preferably, the packing seal is impregnated with a lubricant additive, such as PTFE. Preferably, the first sealing ring, the second sealing ring, the third sealing ring, and the fourth sealing ring have the same cross-section. In particular, the width of the first sealing ring, the second sealing ring, the third sealing ring, and the fourth sealing ring is between 10 mm and 30 mm.The first, second, third, and / or fourth sealing rings are preferably designed for temperatures up to 400°C. This can be reliably achieved using packing seals.

[0007] Further preferably, the seal carrier comprises at least one first spring configured to press the first sealing ring and / or the second sealing ring against the first sealing surface and / or second sealing surface. This ensures a uniform contact force of the third sealing ring and / or the fourth sealing ring, thereby improving the sealing properties. Preferably, the first spring is arranged in a through-bore between the first sealing ring and the second sealing ring in the seal carrier, thereby enabling cost-effective manufacturing. Further preferably, the sealing system comprises a plurality of first springs arranged circumferentially in the seal carrier.

[0008] The seal carrier preferably has at least one second spring configured to press the third sealing ring and / or the fourth sealing ring against the rotating component. This can enable reliable radial sealing of the rotating component. Furthermore, the second spring can compensate for a change in the diameter of the rotating component, which may be due, for example, to thermal expansion.

[0009] Preferably, the third sealing ring and the fourth sealing ring are axially spaced apart to form a gap on the rotating component. The gap is preferably filled with a barrier medium. This can improve the sealing properties of the sealing system. The barrier medium can be a gas or a liquid. Preferably, the barrier medium is a molded fiber packing.

[0010] A gaseous barrier medium can preferably be introduced from the barrier chamber into the intermediate space through an opening in the seal carrier. This allows a barrier gas or purge gas to be easily introduced into the intermediate space to improve the sealing properties of the sealing system.

[0011] Further preferably, an intermediate ring, which in particular has a sensor, is arranged in the intermediate space. The intermediate ring can enable easy spacing of the third sealing ring from the fourth sealing ring. Furthermore, the intermediate ring can enable easy replacement of the third and fourth sealing rings. Arranging a sensor in the intermediate ring can enable monitoring of the sealing properties and wear in the sealing system.

[0012] The seal housing preferably comprises a first plate-shaped side element and a second plate-shaped side element, which are aligned perpendicular to a rotational axis of the sealing system and connected by a connecting element. The three-part plate-shaped design of the seal housing can enable simple and cost-effective manufacturing, especially for large diameters to be sealed.

[0013] Further preferably, the first side element, the second side element, and the connecting element are connected to one another by means of a fastening element. This allows the seal housing to be manufactured simply and cost-effectively. Furthermore, the detachable connection of the components of the seal housing enables easy maintenance of the sealing system, for example, to replace sealing rings. The fastening element can preferably form a screw connection.

[0014] The seal housing preferably has a sealing gas opening for supplying the sealing chamber with a sealing gas. The sealing gas opening is arranged, in particular, in the connecting element. This allows a gas to be easily introduced into the sealing chamber. The gas can preferably also contribute to cooling the sealing system.

[0015] Preferably, the seal housing and / or the seal carrier are segmented along their circumference. This allows for the simple and cost-effective production of a sealing system for sealing large diameters.

[0016] The third sealing ring and the fourth sealing ring preferably have an inner diameter of at least one meter. More preferably, the inner diameter is at least 4 meters, in particular at least 7 meters, and particularly preferably at least 12 meters. This allows for reliable sealing of rotating components with large diameters and compensation of their axial and radial movements.

[0017] The first, second, third, and fourth sealing rings are preferably made of the same material. This allows for reliable sealing by the sealing system while being cost-effective to manufacture.

[0018] Furthermore, the invention relates to a ball mill or a rotary kiln with a sealing system as described above. The sealing system can absorb axial and radial movements of a rotating component in the ball mill or rotary kiln, preventing them from being transmitted to a stationary component of the ball mill or rotary kiln. Short description of the drawings

[0019] A preferred embodiment of the invention will be described in detail below with reference to the accompanying drawings. It shows: Fig. 1 a perspective view of a sealing system according to a preferred embodiment of the invention and Fig. 2 a further perspective view of the sealing system according to the preferred embodiment of the invention.

[0020] The following is based on the Fig. 1 and Fig. 2 a sealing system 1 for a ball mill is described in detail.

[0021] Fig. Figure 1 shows the sealing system 1 for sealing a process side 5 within a rotating component 2 against an atmosphere side 6, which is arranged radially outside the rotating component 2. The sealing system 1 has an annular seal housing 10, which is attached to a stationary component 3.

[0022] The annular seal housing 10 has, in a section parallel to the rotational axis of the seal housing 10, a radially inwardly open U-shaped cross-section, which forms a receiving space 40. A seal carrier 20 is arranged within the U-shaped cross-section.

[0023] A first sealing ring 21, a second sealing ring 22, a third sealing ring 23, and a fourth sealing ring 24 are arranged on the seal carrier 20. The first sealing ring 21 seals against a first sealing surface 11 of the seal housing 10 via a first contact surface 21a. The second sealing ring 22 seals against a second sealing surface 12 of the seal housing 10 via a second contact surface 22a. Furthermore, the third sealing ring 23 and the fourth sealing ring 24 seal radially against the rotating component 2 with a third contact surface 23a and a fourth contact surface 24a. The seal carrier 20 is thus mounted in a floating manner in the seal housing 10, whereby radial movements of the rotating component 2 can be absorbed. The rotating component 2 is cylindrical at the contact surface with the sealing system 1, so that the rotating component 2 can move axially relative to the sealing system 1.

[0024] The first sealing ring 21, the second sealing ring 22, the third sealing ring 23, and the fourth sealing ring 24 are packing seals with a rectangular cross-section made of a braided fiber material. This allows a finished sealing gap to be formed, enabling reliable sealing properties. The rectangular cross-section of all sealing rings 21, 22, 23, and 24 preferably has a width between 10 mm and 30 mm.

[0025] The first sealing ring 21 and the second sealing ring 22 are arranged in two opposing grooves 8 in the seal carrier 20. A through-bore 9 is formed between the grooves 8, in which a first spring 25 is arranged. The first spring 25 contacts the first sealing ring 21 and the second sealing ring 22 via pressure rings 19 and presses them outward against the first sealing surface 11 and the second sealing surface 12.

[0026] The third sealing ring 23 and the fourth sealing ring 24 are arranged at a distance from one another on an inner radius of the seal carrier 20. The distance between the third sealing ring 23 and the fourth sealing ring 24 is formed by an intermediate ring 28, which is arranged coaxially between the third sealing ring 23 and the fourth sealing ring 24. A gap 27 is formed between the third sealing ring 23, the intermediate ring 28, the fourth sealing ring 24, and the rotating component 2.

[0027] A sensor system is preferably arranged in the intermediate ring 28, which can detect operating parameters of the sealing system 1, such as the wear of the third sealing ring 23 and the fourth sealing ring 24.

[0028] A barrier medium is preferably arranged in the intermediate space 27, which can improve the sealing properties of the sealing system 1. For example, a moldable, molded fiber packing can be arranged in the intermediate space 27 as a barrier medium.

[0029] A barrier chamber 4 is arranged radially between the seal carrier 20 and the seal housing 10. A barrier gas can be introduced into the barrier chamber 4 via a barrier gas opening 16 in the seal housing 10. The barrier gas can also be introduced into the intermediate space 27 through openings 7 in the seal carrier 20.

[0030] In the seal carrier 20, a second spring 26 is arranged in each of two blind holes 18, which exert a spring force on the third sealing ring 23 and the fourth sealing ring 24 in order to press them against the rotating component 2. A pressure ring can also be arranged between the second spring 26 and the third sealing ring 23 or fourth sealing ring 24, which can better transmit the spring force to the sealing ring.

[0031] The sealing system 1 preferably comprises a plurality of first springs 25 and second springs 26, which are arranged circumferentially in the seal carrier 20 in order to exert a circumferentially uniform force on the sealing rings 21, 22, 23, 24.

[0032] The seal housing 10 comprises a first plate-shaped side element 13 and a second plate-shaped side element 14, which are oriented perpendicular to a rotational axis of the sealing system 1. The first side element 13 and the second side element 14 are connected to one another by means of a connecting element 15 at a radially outer end. Thus, the first side element 13 and the second side element 14 form the legs of the U-shaped cross section of the seal housing 10.

[0033] The first sealing surface 11 is located on an inner surface of the first side element 13 and the second sealing surface 12 is located on an inner surface of the second side element 14. A plurality of bores 17 are arranged circumferentially in the second side element 14 and extend into the connecting element 15 and the first side element 13 in order to connect the first side element 13, the second side element 14 and the connecting element 15 by means of a fastening element, such as a screw.

[0034] Fig. 2 shows a further perspective view of the sealing system 1 from Fig. 1. In this case Fig. 2, the first side element 13 is hidden. This shows the holes 17 in the connecting element 15.

[0035] Furthermore, Fig.2 shows a clamping element 29 that adjoins the seal carrier 20 and the fourth sealing ring 24. The clamping element 29 can be attached to the seal carrier 20 by means of a fastening element and can exert an axial force on the fourth sealing ring 24, the intermediate rings 28 arranged thereon, and the third sealing ring 23, which is laterally located on the seal carrier 20 at a shoulder 20a. This allows the third sealing ring 23 and the fourth sealing ring 24 to be axially secured in the seal carrier 20 while still retaining radial mobility. Using the fastening means, the clamping element 29 can be easily removed from the seal carrier 20, allowing the third sealing ring 23 and the fourth sealing ring 24 to be replaced.

[0036] An inner diameter of the third sealing ring 23 and the fourth sealing ring 24 is preferably at least 7 meters and corresponds to the outer diameter of the rotating component 2 in the area of ​​the sealing system 1.

[0037] For ease of manufacture and assembly, the seal housing 10 and the seal carrier 20 are preferably segmented. Further preferably, the segments can be connected to one another by means of positive-locking connections.

[0038] The seal carrier 20 is preferably arranged in a rotationally fixed manner on the seal housing 20. This can be achieved, for example, by means of a torque driver and a radial centering device.

[0039] Thus, a sealing system for very large diameters can be provided, which enables a seal between a rotating component and a stationary component, wherein the sealing system 1 can absorb axial and radial movements of the rotating component 2. List of reference symbols 1 sealing system 2 Rotating component 3 Stationary component 4 Locking chamber 5 Process page 6 Atmosphere side 7 Opening 8 grooves 9 Through hole 10 Seal housing 11 First sealing surface 12 Second sealing surface 13 First page element 14 Second page element 15 Connecting element 16 Seal gas opening 17 Hole 18 blind hole drilling 19 pressure rings 20 seal carriers 20a paragraph 21 First sealing ring 21a first contact surface 22a second contact surface 23a third contact surface 24a fourth contact surface 22 Second sealing ring 23 Third sealing ring 24 Fourth sealing ring 25 First Spring 26 Second spring 27 space 28 intermediate ring 29 clamping element 40 recording room

Claims

[1] Sealing system for sealing between a rotating component (2) and a stationary component (3), comprising • an annular seal housing (10) with a radially inwardly open U-shaped cross-section and • a seal carrier (20) on which a first sealing ring (21), a second sealing ring (22), a third sealing ring (23) and a fourth sealing ring (24) are arranged, • wherein the seal carrier (20) is arranged radially movable in the U-shaped cross section of the seal housing (10), wherein a barrier chamber (4) is formed radially between the seal housing (10) and the seal carrier (20), • wherein the seal housing (10) is designed to be attached to the stationary component (3), • wherein the first sealing ring (21) is designed to seal with a first contact surface (21a) axially against a first sealing surface (11) of the seal housing (10), • wherein the second sealing ring (22) is designed to seal with a second contact surface (22a) axially against a second sealing surface (12) of the seal housing (10) and • wherein the third sealing ring (23) and the fourth sealing ring (24) are designed to seal radially against the rotating component (2) with a third contact surface (23a) and fourth contact surface (24a). [2] Sealing system according to claim 1, wherein the first sealing ring (21), second sealing ring (22), third sealing ring (23) and / or fourth sealing ring (24) is a packing seal, in particular with a rectangular cross-section made of a fiber material, in particular of a braided fiber material. [3] Sealing system according to one of the preceding claims, wherein the seal carrier (20) has at least one first spring (25) which is designed to press the first sealing ring (21) and / or the second sealing ring (22) against the first sealing surface (11) and / or second sealing surface (12). [4] Sealing system according to one of the preceding claims, wherein the seal carrier (20) has at least one second spring (26) which is designed to press the third sealing ring (23) and / or the fourth sealing ring (24) against the rotating component (2). [5] Sealing system according to one of the preceding claims, wherein the third sealing ring (23) and the fourth sealing ring (24) are axially spaced apart in order to form an intermediate space (27) on the rotating component (2), in particular filled with a barrier medium. [6] Sealing system according to claim 5, wherein a gaseous barrier medium can be introduced from the barrier chamber (4) into the intermediate space (27) through an opening (7) in the seal carrier (20). [7] Sealing system according to claim 5 or 6, wherein an intermediate ring (28) is arranged in the intermediate space (27), which in particular has a sensor system. [8] Sealing system according to one of the preceding claims, wherein the seal housing (10) comprises a first plate-shaped side element (13) and a second plate-shaped side element (14) which are aligned perpendicular to a rotation axis of the sealing system (1) and are connected by a connecting element (15). [9] Sealing system according to claim 8, wherein the first side element (13), the second side element (14) and the connecting element (15) are connected by means of a fastening element. [10] Sealing system according to one of the preceding claims, wherein the sealing housing (10) has a sealing gas opening (16), in particular in the connecting element (15), in order to supply the sealing chamber (4) with a sealing gas. [11] Sealing system according to one of the preceding claims, wherein the seal housing (10) and / or the seal carrier (20) is segmented on the circumference. [12] Sealing system according to one of the preceding claims, wherein the third sealing ring (23) and the fourth sealing ring (24) have an inner diameter of at least 1 m, in particular of at least 4 m, in particular of at least 7 m, further in particular of at least 12 m. [13] Sealing system according to one of the preceding claims, wherein the first sealing ring (21), the second sealing ring (22), the third sealing ring (23) and the fourth sealing ring (24) are made of the same material. [14] Ball mill or rotary kiln with a sealing system according to one of claims 1 to 13.

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