Mechanical seal assembly with improved axial load support.

Abstract

The present invention relates to a mechanical seal assembly (1) for sealing between a high pressure region (8) and a low pressure region (9) on a rotating component (7), comprising a mechanical seal (2) having a rotating sliding ring (3) with a first sliding face (30) and a stationary sliding ring (4) with a second sliding face (40), with a seal gap (5) defined between said sliding faces (30, 40), a sliding ring carrier (31) for the rotating sliding ring (3) configured to connect said rotating sliding ring (3) to a rotating component (7) in a rotationally fixed manner, said sliding ring carrier (31) having a sleeve region (32), and a force support mechanism (6) configured to support an axial force (F) on said mechanical seal assembly (1), said force support mechanism (6) being configured to support said sliding ring (3) in a rotationally fixed manner, said sliding ring carrier (31) having a sleeve region (32), and a force support mechanism (6) configured to support an axial force (F) on said mechanical seal assembly (1), said force support mechanism (6) being configured to support said axial force (F) on said rotating component (7). The mechanical seal assembly (1) is disposed on an end face (32a) of a sleeve region (32) of a ring carrier (31), and the force support mechanism (6) comprises a clamp sleeve (60), a conical sleeve (61) and a split ring (62) having at least two segments (621, 622), a conical connection between a first conical surface (60a) of the clamp sleeve (60) and a second conical surface (61a) of the conical sleeve (61) is formed between the clamp sleeve (60) and the conical sleeve (61), the clamp sleeve (60) abuts against the end face (32a) of the sleeve region (32), and the conical sleeve (61) abuts against a side surface (62a) of the split ring (62).

Description

[Technical field]

[0001] The present invention relates to a mechanical seal assembly for sealing between high and low pressure areas on a shaft with improved support of axial forces that may act on the mechanical seal assembly during operation. [Background technology]

[0002] Mechanical seal assemblies of various configurations have been known in the past. In particular, for gas seals, 5 In high-pressure applications with pressures exceeding 100 Pa, very large axial forces may act on the components of the mechanical seal assembly. To absorb these large forces, it is known to use so-called split rings, consisting of several circumferential segments, to transmit the axial forces to the shaft, etc. When these split rings deform, they generate circumferential undulations, and in extreme cases, they may be pushed into the sliding surface of the sliding ring due to elastic deformation. However, in order not to unnecessarily limit the performance of the mechanical seal, undulations on the sliding surface must be absolutely avoided. In the prior art, elastic secondary sealing elements were used between the split ring and the mechanical seal to reduce undulations that can be transmitted from the split ring to the sliding surface. These can be elastically deformed when axial forces are generated, thus reducing the risk of transmitting undesirable undulations to the sliding surface of the mechanical seal. In high-pressure applications and in sealing operations where the sealed medium is at high temperatures, elastic secondary sealing elements cannot be used, or can only be used to a limited extent. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, an object of the present invention is to provide a mechanical seal assembly that can prevent the transmission of undulations from a split ring to the sliding surface of the mechanical seal assembly, has a simple structure, can be manufactured simply and at low cost, and is particularly suitable for high-pressure and high-temperature applications. [Means for solving the problem]

[0004] This object is achieved by a mechanical seal assembly having the features of claim 1. The dependent claims specify preferred embodiments of the invention.

[0005] On the other hand, the mechanical seal assembly according to the invention having the features of claim 1 has the advantage that the axial force acting on the mechanical seal assembly can be absorbed and transmitted to the rotating part significantly better. In particular, it is possible to prevent waviness from being applied to the sliding surface of the mechanical seal assembly when an axial force is generated. According to the invention, the mechanical seal assembly comprises a rotating sliding ring having a first sliding surface and a fixed sliding ring having a second sliding surface, and is provided with a mechanical seal for sealing between a high pressure area and a low pressure area, such as a shaft, and a seal gap is defined between the sliding surfaces of the sliding rings. Furthermore, the rotating sliding ring is provided with a sliding ring carrier, which is configured to perform a rotationally fixed connection with the rotating part, in particular the shaft. The sliding ring carrier comprises a sleeve region. Furthermore, the mechanical seal assembly comprises a force support mechanism configured to support the axial force acting on the mechanical seal assembly. The force support mechanism is arranged on an end face of the sleeve region of the sliding ring carrier. The force support mechanism comprises a clamping sleeve, a conical sleeve and a split ring having at least two segments. The split ring is divided into several circumferential segments in the radial direction of the mechanical seal assembly, which are connected to each other on the rotating part in the assembled state. Furthermore, a conical connection is formed between the clamping sleeve and the conical sleeve. The clamping sleeve abuts against the end face of the sleeve region of the sliding ring carrier, and the conical sleeve abuts against the side face of the split ring.

[0006] Thus, when an axial force is applied to the mechanical seal assembly, the force is transferred from the sliding ring carrier to the clamping sleeve, from the clamping sleeve to the conical sleeve, from the conical sleeve to the split ring, and from the split ring to the rotating part. The axial force is thus transferred via four connection surfaces, namely, a first connection surface between the sleeve area and the clamping sleeve, a second connection surface at the conical connection between the clamping sleeve and the conical sleeve, a third connection surface between the conical sleeve and the split ring, and a fourth connection surface between the split ring and the rotating part.

[0007] A particular advantage of the configuration according to the invention is that the conical connection between the clamping sleeve and the conical sleeve allows the radial axial force component to be transferred directly to the rotating component via the inner circumference of the conical sleeve, thus significantly reducing the axial force that ultimately remains on the fourth connecting surface and is transferred to the rotating component, thereby preventing the separation point of the split ring from being pressed against the sliding surface of the mechanical seal assembly.

[0008] In order to achieve the most compact possible configuration and to ensure a reliable force transmission from the clamping sleeve to the conical sleeve, the clamping sleeve is preferably provided with a receiving space for the conical sleeve, which is preferably able to be positioned in the receiving space of the clamping sleeve to a large extent, in particular to an axial extent of 80% or more.

[0009] Preferably, the receiving space of the clamping sleeve comprises a first inner conical surface and the conical sleeve comprises a second outer conical surface, said two conical surfaces forming a conical connection between the clamping sleeve and the conical sleeve.

[0010] The conical connection is preferably arranged at an angle α of 35°±8°, in particular 35°±3°, relative to the central axis X-X of the mechanical seal. Selection of an angle α<45° results in a greater transmission of radial forces to the rotating part via the conical sleeve than of axial forces in the direction of the split ring.

[0011] It is particularly preferred that the average diameter of the split ring is greater than the inner diameter of the conical sleeve, so that forces are better transferred from the conical sleeve to the split ring, and in particular in this contact area of ​​the split ring, deformations inherent in the split ring are reduced.

[0012] It is particularly preferred that the clamping sleeve, the split rings, the sliding ring carrier and the conical sleeve are made of a metallic material, in particular the same metallic material. Preferably, steel is used as this metallic material. This means that the mechanical seal assembly can be used in high temperature applications in particular where the use of elastic sealing elements is not possible, since the high temperatures would destroy the elastic sealing elements, and where the use of split rings would likely lead to waviness on the sliding surfaces of the sliding rings. If different materials are used for the clamping sleeve, the split rings, the sliding ring carrier and the conical sleeve, it is preferred that the different materials have the same or very similar (±10%) coefficients of thermal expansion.

[0013] It is particularly preferred that the split ring is arranged in a groove of a rotating part, in particular in a groove of a shaft.

[0014] An axial gap is also preferably provided in the inner peripheral area between the clamping sleeve and the conical sleeve, which provides the force support mechanism with at least certain damping properties when an axial force is introduced and thus allows a reliable transmission of the axial force from the sleeve area of ​​the sliding ring carrier to the rotating component via the force transmission path.

[0015] In order to further improve the transmission of axial forces, it is preferred to form a threaded connection between the sleeve region of the sliding ring carrier and the clamping sleeve, which preferably comprises a number of circumferentially arranged threaded bolts which are inserted through the clamping sleeve and screwed into the end face of the sleeve region.

[0016] The mechanical seal assembly is preferably a gas seal for sealing a gaseous medium. The gaseous medium is preferably a 200×10 5It is particularly preferable to carry out the treatment under high pressure of 100 MPa or more and at high temperature of 400° C. or more.

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic cross-sectional view of a mechanical seal assembly according to a preferred embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 2 is an enlarged schematic partial cross-sectional view of the mechanical seal assembly of FIG. 1. [Figure 4] FIG. 2 is a schematic cross-sectional view of a clamp sleeve of the mechanical seal assembly of FIG. 1. [Diagram 5] FIG. 2 is a schematic cross-sectional view of a conical sleeve of the mechanical seal assembly of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] A mechanical seal assembly 1 according to a preferred embodiment of the present invention will be described in detail below with reference to FIGS.

[0020] As can be seen in Figure 1, the mechanical seal assembly 1 comprises a mechanical seal 2 with a rotating sliding ring 3 and a fixed sliding ring 4. The rotating sliding ring 3 has a first sliding face 30 and the fixed sliding ring 4 has a second sliding face 40. A seal gap 5 is defined between the two sliding faces 30, 40 of the sliding rings 3, 4.

[0021] As can be seen in FIG. 1, the mechanical seal assembly 1 seals a high pressure region 8 from a low pressure region 9 on a shaft 7. The high pressure region 8 includes, among other things, a 200×10 5 It is preferable that the gas, which is the medium to be sealed, is present under high pressure of 100 Pa or more.

[0022] The rotating sliding ring 3 is connected to the shaft 7 for co-rotation by a sliding ring carrier 31. The sliding ring carrier 31 comprises a sleeve region 32 arranged on the shaft 7 and a holding region 33 which partially surrounds the rotating sliding ring 3. Thus, when the shaft 7 rotates, forces are transmitted from the shaft 7 to the sliding ring carrier 31 and from there to the rotating seal ring 3.

[0023] Also, a metal seal 34 without a resilient secondary seal is preferably formed between the sliding ring carrier 31 and the rotating sliding ring 3. This means that no resilient secondary sealing element is required between the sliding ring carrier 31 and the rotating sliding ring 3 to seal the gap between these two components, so that both high pressure and high temperature applications can be carried out without any problems.

[0024] The mechanical seal assembly 1 further includes a force support mechanism 6. The force support mechanism 6 is shown in detail in Fig. 3. The force support mechanism 6 includes a clamp sleeve 60, a conical sleeve 61, and a split ring 62.

[0025] Split ring 62 is a ring split into two circumferential segments, in this exemplary embodiment split ring 62 comprises a first segment 621 and a second segment 622. The two segments are connected to each other via a threaded connection 63 (see FIG. 2). Alternatively, the split ring is held by pressing a sleeve over it.

[0026] The split ring 62 is disposed in a groove 70 in the shaft 7 .

[0027] The clamping sleeve 60 is shown in more detail in Fig. 4. In particular, the clamping sleeve 60 comprises a first conical surface 60a and an accommodation space 16. Like the first conical surface 60a, the accommodation space 16 is formed radially inside, i.e. on the side of the clamping sleeve 60 facing the shaft 7. The accommodation space 16 serves to accommodate a conical sleeve 61, as shown in Figs. 1 and 3.

[0028] The conical sleeve 61 is shown in more detail in Figure 5. The conical sleeve 61 comprises a second conical surface 61a. Furthermore, the conical sleeve 61 has an inner circumference 61b, by means of which the conical sleeve 61 is placed on the shaft 7.

[0029] The force support mechanism 6 is configured to support an axial force F on the mechanical seal assembly 1. Such an axial force F may arise during operation of the mechanical seal assembly, particularly in response to and especially when the loads vary on the machine being sealed.

[0030] 1 and 3, a conical connection is formed between the clamping sleeve 60 and the conical sleeve 61, which connection is formed by a first conical surface 60a of the clamping sleeve 60 and a second conical surface 61a of the conical sleeve 61. The conical sleeve 61 is received in the receiving space 16 of the clamping sleeve 60.

[0031] 1 and 3, the clamping sleeve 60 rests in the assembled state against the end face 32a of the sleeve region 32 of the sliding ring carrier 31. Furthermore, the conical sleeve 61 rests against a side surface 62a of the split ring 62.

[0032] Furthermore, the conical sleeve 61 has an inner diameter D1 that is smaller than the average diameter D2 of the split ring 62 (see FIG. 1), which ensures that the force is transmitted to the radially inner region of the split ring 62, and that the axial force is transmitted from the split ring 62 to the shaft 7 without significant leverage effects.

[0033] The conical connection between the clamp sleeve 60 and the conical sleeve 61 has an angle α with respect to the central axis XX of the mechanical seal assembly 1 (see FIG. 1). The angle α is preferably in the range of 35°±3°.

[0034] The clamping sleeve 60 is connected to the sleeve region 32 of the sliding ring carrier 31 by means of bolts 15. Preferably, several bolts 15 are arranged equidistant from one another along the circumference of the clamping sleeve.

[0035] The sliding ring carrier 31, the clamping sleeve 60, the conical sleeve 61 and the split ring 62 are all made of steel, preferably the same steel, which allows the mechanical seal assembly 1 to be used in high pressure applications as well as high temperature applications.

[0036] As shown in Fig. 3, four connection surfaces are provided between the sliding ring carrier 31 and the shaft 7 for transmitting the axial force F. A first connection surface 11 is formed between the sleeve region 32 and the clamping sleeve 60. A second connection surface 12, which forms a conical connection, is formed between the clamping sleeve 60 and the conical sleeve 61. A third connection surface 13 is formed between the conical sleeve 61 and the side surface 62a of the split ring 62. A fourth connection surface 14 is formed between the split ring 62 and the shaft 7 in the region of the groove 70 (see Fig. 3).

[0037] Thus, when an axial force F acts on the mechanical seal assembly 1 during operation of the mechanical seal assembly 1, this force is transmitted to the force support mechanism 6 arranged on the shaft 7 via the sliding ring carrier 31. By providing the conical second connecting surface 12 between the clamping sleeve 60 and the conical sleeve 61, the force F is divided into an axial component F1 and a radial component F2. The radial component F2 is then transmitted directly to the shaft 7 via the inner circumference 61b of the conical sleeve 61. This significantly reduces the remaining force transmitted from the conical sleeve 61 to the split ring 62 and from there to the shaft 7 via the groove 70.

[0038] This makes it possible to reduce swells caused by the load generated by deformation of the split ring 62 when the axial force F is applied to a level where no swells are applied to the sliding surfaces 30, 40 of the sliding ring.

[0039] Furthermore, an axial gap 10 exists between the clamping sleeve 60 and the conical sleeve 61 (see FIG. 3 ). This axial gap 10 provides a certain damping effect when an axial force F occurs, which allows a certain deformation inherent to the components of the force support mechanism 6.

[0040] Since the deformation of the steel used as the material for the sliding ring carrier 31, the clamp sleeve 60, the conical sleeve 61 and the split ring 62 is relatively small, the configuration of the components of the mechanical seal assembly 1 can also be improved.

[0041] In particular, the magnitude of the introduction of undulations caused by the split ring 62 on the sliding surfaces 30, 40 can be maximized by selecting the angle α of the conical connection between the clamping sleeve 60 and the conical sleeve 61. [Explanation of symbols]

[0042] 1 Mechanical Seal Assembly 2. Mechanical seal 3 Rotating sliding ring 4 Fixed Mechanical Seal 5 Seal Gap 6 Force support mechanism 7 Shafts / rotating parts 8 High Pressure Region 9. Low Pressure Region 10 Axial gap 11 First connection surface 12 Second connection surface 13 Third connection surface 14 Fourth connection surface 15 Volts 16 Storage Space 30 First sliding surface 31 Sliding ring carrier 32 Sleeve Area 32a End face of sleeve area 33 Holding area 34 Metal Seal 40 Second sliding surface 60 Clamp sleeve 60a First cone surface 61 Conical Sleeve 61a Second cone surface 61b Inner circumference 62 Split Ring 62a Side of split ring 63 Threaded connection 621 First Segment 622 Second Segment 70 groove D1 Inner diameter of conical sleeve D2 Average diameter of split ring F Axial force F1 Axial component of axial force F2 Radial component of axial force XX center axis α angle

Claims

1. A mechanical seal assembly (1) for sealing between a high pressure area (8) and a low pressure area (9) on a rotating component (7), comprising: A mechanical seal (2) comprising a rotating sliding ring (3) having a first sliding surface (30) and a fixed sliding ring (4) having a second sliding surface (40), with a seal gap (5) defined between the sliding surfaces (30, 40); a sliding ring carrier (31) for a rotating sliding ring (3) configured to connect said rotating sliding ring (3) to a rotating part (7) in a rotationally fixed manner and having a sleeve region (32); a force support mechanism (6) configured to support an axial force (F) applied to the mechanical seal assembly (1); Equipped with The force support mechanism (6) is arranged on an end face (32a) of the sleeve region (32) of the sliding ring carrier (31); The force support mechanism (6) comprises a clamp sleeve (60), a conical sleeve (61) and a split ring (62) having at least two segments (621, 622); a conical connection between the first conical surface (60a) of the clamping sleeve (60) and the second conical surface (61a) of the conical sleeve (61) is formed between the clamping sleeve (60) and the conical sleeve (61); the clamping sleeve (60) abuts against the end face (32a) of the sleeve region (32), and the conical sleeve (61) abuts against the side face (62a) of the split ring (62); Mechanical seal assembly (1).

2. The mechanical seal assembly (1) according to claim 1, wherein the clamp sleeve (60) comprises an accommodation space (16) for accommodating the conical sleeve (61).

3. 3. The mechanical seal assembly (1) of claim 2, wherein the receiving space (16) of the clamping sleeve (60) has a first inner conical surface (60a) and the conical sleeve (61) has a second outer conical surface (60a).

4. The mechanical seal assembly (1) according to claim 1, wherein the conical connection has an angle (α) of 35°±8° with respect to a central axis (X-X) of the mechanical seal assembly (1).

5. The mechanical seal assembly (1) of claim 1, wherein the average diameter (D2) of the split ring (62) is greater than the inner diameter (D1) of the conical sleeve (61).

6. The mechanical seal assembly (1) of claim 1, wherein the sliding ring carrier (31), the clamping sleeve (60), the conical sleeve (61) and the split ring (62) are made of metallic materials.

7. The mechanical seal assembly (1) of claim 1, wherein the split ring (62) is configured to be received within a groove (70) of the rotating component (7).

8. 2. The mechanical seal assembly (1) of claim 1, wherein an axial gap (10) is formed in an inner peripheral area between the clamp sleeve (60) and the conical sleeve (61).

9. The mechanical seal assembly (1) of claim 1, wherein a threaded connection is formed between the clamping sleeve (60) and the sliding ring carrier (31).

10. The mechanical seal assembly (1) according to any one of claims 1 to 9, wherein a metal seal (34) without an elastic secondary sealing element is formed between the sliding ring carrier (31) and the rotating sliding ring (3).

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