Hybrid seal

Abstract

The invention relates to a method for producing a labyrinth seal (1) for sealing a sealing region (2) between a rotor and a stator of a rotary machine, in which method a seal carrier (8) and a sealing element (3) are produced, wherein the sealing element (3) has projecting seal rings (4) which are arranged opposite a rotor surface, wherein the sealing element (3) and the seal carrier (8) are interlockingly connected to one another.

Description

[0001] Description

[0002] Hybrid seal

[0003] The invention relates to a labyrinth seal for sealing a sealing area between a rotor and a stator of a rotary machine, wherein the labyrinth seal comprises: a sealing element having protruding sealing rings which can be arranged opposite a rotor surface, further comprising a seal carrier which is designed to receive the sealing element, wherein the sealing element is positively connected to the seal carrier.

[0004] Furthermore, the invention relates to a method for producing a labyrinth seal for sealing a sealing area between a rotor and a stator of a rotary machine, in which a seal carrier and a sealing element are created, wherein the sealing element has protruding sealing rings which are arranged opposite a rotor surface, wherein the sealing element is positively connected to the seal carrier.

[0005] In order to reduce efficiency losses due to leaks, sealing is required at points of different pressure in rotating machines such as turbomachines. Seals between a rotating part, e.g. a shaft, and a stator part, such as a housing part, are often designed as non-contact labyrinth seals. In order to take thermal expansion, centrifugal expansion and oscillation of the rotor in the radial positions and when passing through critical speeds, the radial sealing clearance must not be too small. If the sealing gap is too small, this will result in rubbing and thus damage to the labyrinth tips and, in the worst case, in the rotor becoming distorted.

[0006] The state of the art includes resilient sealing segments of a labyrinth seal that deflect when touched, thus preventing major damage. Labyrinth seals made of polymer materials are also known. However, such labyrinth seals made of high-performance polymers are comparatively expensive. Furthermore, the thermal expansion of plastic is greater than that of metallic materials, which complicates machine design.

[0007] Labyrinth seals made of polymer materials produced using additive manufacturing are currently being investigated. Due to the available pressure space in the labyrinth seals used in the machines, the size of the labyrinth seal as a ring is limited to small diameters.

[0008] Hybrid labyrinth seals are manufactured by a material-locking connection of two or more materials.

[0009] Against this background, the invention has set itself the task of providing a labyrinth seal that can be manufactured comparatively cheaply.

[0010] This object is achieved by a labyrinth seal for sealing a sealing area between a rotor and a stator of a rotary machine, wherein the labyrinth seal comprises: a sealing element having protruding sealing rings which can be arranged opposite a rotor surface, further comprising a seal carrier which is designed to receive the sealing element, wherein the sealing element is positively connected to the seal carrier.

[0011] Furthermore, the objects are also achieved by a method for producing a labyrinth seal for sealing a sealing area between a rotor and a stator of a rotating machine, in which a seal carrier and a sealing element are created, wherein the sealing element has protruding sealing rings which are arranged opposite a rotor surface, wherein the sealing element is positively connected to the seal carrier.

[0012] The invention enables a comparatively inexpensive production of a labyrinth seal from different materials.

[0013] The invention is based on the idea that there are advantages to forming a labyrinth seal from different materials and to design the production in such a way that, on the one hand, it is carried out comparatively cheaply by means of a positive connection and, on the other hand, a service-friendly solution is available due to the detachable positive connection.

[0014] Among other things, it is proposed to arrange a steel seal carrier and to design it in such a way that it accommodates segmented sealing elements containing the labyrinth tips. The sealing element is made of a polymer material, such as PEEK. The sealing elements are pre-stressed and positively connected to the seal carrier, which is similar to a click connection. This allows the segment-like sealing elements to be easily assembled into a ring and reworked.

[0015] The seal carrier and the sealing element are advantageously made of different materials, with the connection of the different materials being pre-stressed, form-fitting and not material-fitting.

[0016] Such a connection, which can also be referred to as a click connection, can be created quickly and easily without any tools. If wear occurs, the elements can be replaced and the seal carrier reused. Due to the low polymer content, the influence of thermal expansion is minimal.

[0017] By choosing the polymer material the costs are lower.

[0018] Advantageous further developments are specified in the subclaims.

[0019] The above-described properties, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the embodiments, which are explained in more detail in connection with the drawings.

[0020] Identical components or components with the same function are marked with the same reference symbols.

[0021] Exemplary embodiments of the invention are described below with reference to the drawings. These are not intended to represent the exemplary embodiments to scale; rather, where useful for explanation, the drawings are presented in a schematic and / or slightly distorted form. For supplements to the teachings immediately apparent in the drawings, reference is made to the relevant prior art.

[0022] It shows :

[0023] Figure 1 is a schematic representation of an embodiment of a labyrinth seal according to the invention

[0024] Figure 1 shows a schematic representation of an embodiment of a labyrinth seal 1 according to the invention.

[0025] The labyrinth seal 1 is designed to effectively seal a sealing area 2 between a stator (not shown) and a rotor (not shown). The stator and the rotor are part of a rotating machine, such as a turbomachine or a turbomachine.

[0026] For this purpose, the labyrinth seal 1 comprises a sealing element 3. The sealing element 3 is formed from a material and has sealing rings 4 that extend into and protrude from the sealing area 2. The sealing rings 4 are arranged opposite a rotor surface (not shown).

[0027] The sealing element 3 has a base plate 5, on one side 6 of which the sealing rings 4 are arranged, and on the rear side 7 of which a seal carrier 8 is arranged. The seal carrier 8 is designed to receive the sealing element 3. According to the invention, the seal carrier 8 is positively connected to the sealing element 3.

[0028] For this purpose, the sealing element has a V-shaped projection 9. This projection 9 has a first leg 10 and a second leg 11, which together form a V. The projection 9 is arranged on the rear side 7 of the sealing element 3.

[0029] A recess 12 is arranged in the seal carrier 8 and is designed such that the V-shaped projection 9 projects into it. For this purpose, the recess 12 must be designed to complement the projection 9. By means of the legs 10 and 11, which are inclined relative to a radial direction 13, a positive connection is achieved by the side surfaces 14 and 15 of the recess 12, which are also inclined at the same angle.

[0030] The rotor (not shown) is mounted for rotation about a rotation axis 16. The radial direction 13 is arranged substantially perpendicular thereto. The projection 9 is formed from an elastic material. This allows the two legs 10 and 11 to be prestressed relative to one another, so that during assembly, the sealing element 3 can be inserted into the recess 12 in the radial direction 13. In an alternative embodiment, however, the sealing element 3 can also be inserted in a circumferential direction.

[0031] The seal carrier 8 is made of steel. The sealing element 3 is made of a polymer material. The polymer material is, for example, PEEK.

[0032] Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited to the disclosed examples and other variants can be derived by the person skilled in the art without departing from the scope of the invention.

Claims

Patent claims 1. Labyrinth seal (1) for sealing a sealing area (2) between a rotor and a stator of a rotating machine, wherein the labyrinth seal (1) comprises: a sealing element (3) having protruding sealing rings (4) which can be arranged opposite a rotor surface, further comprising a seal carrier (8) which is designed to receive the sealing element (3), characterized in that the sealing element (3) is positively connected to the seal carrier (8).

2. Labyrinth seal (1) according to claim 1, wherein the seal carrier (8) and the sealing element (3) are made of different materials.

3. Labyrinth seal (1) according to claim 2, wherein the seal carrier (8) is made of steel.

4. Labyrinth seal (1) according to claim 2 or 3, wherein the sealing element (3) is formed from a polymeric material.

5. Labyrinth seal (1) according to claim 4, wherein the polymeric material is PEEK.

6. Labyrinth seal (1) according to one of the preceding claims, wherein the sealing element (3) is formed in a segment-like manner.

7. Labyrinth seal (1) according to one of the preceding claims, wherein the sealing element (3) has a V-shaped projection (9) which is provided with a complementary to the V-shaped projection (9) formed recess (12) is materially connected.

8. Labyrinth seal (1) according to one of the preceding claims, wherein the sealing element (3) is formed of a single material.

9. Method for producing a labyrinth seal (1) for sealing a sealing area (2) between a rotor and a stator of a rotating machine, in which a seal carrier (8) and a sealing element (3) are created, wherein the sealing element (3) has protruding sealing rings (4) which are arranged opposite a rotor surface, wherein the sealing element (3) and the seal carrier (8) are positively connected to one another.

10. The method according to claim 9, wherein the sealing element (3) is arranged in segments around a rotor.

11. Method according to claim 9 or 10, wherein the sealing element (3) is pre-tensioned and positively connected to the seal carrier (8).

12. The method according to claim 9, 10 or 11, wherein the sealing element (3) is inserted into the seal carrier (8) in a circumferential direction.

13. Method according to one of claims 9 to 12, wherein the sealing element (3) is formed from a polymeric material.

14. Method according to one of claims 9 to 13, wherein the seal carrier (8) is formed from steel.

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