Seal for sealing a gap between an opening in a housing part and a tube that moves through the housing part in an axial and / or lateral direction

Abstract

The invention relates to a seal for sealing a gap between an opening in a housing part and a tube guided through the housing part in an axially and / or laterally movable direction, and to a system of at least two seals according to the invention. Previous compensators have a complex design and are therefore cumbersome to replace. The seal according to the invention and the system of multiple seals have a simplified design and facilitate the replacement of a tube and / or the seal.

Description

Area:

[0001] The invention relates to a seal for sealing a gap between an opening in a housing part and a tube which is movable in the axial and / or lateral direction and guided through the housing part. State of the art:

[0002] In process engineering plants, especially metallurgical plants, the task often arises of guiding a movable tube through an opening in a housing. Examples of tubes in this sense can be burner tubes, blowing lances, or tubular feeders for additives. Particularly in metallurgical plants, such as a VOD plant or a vacuum remelting plant, the melt must be shielded from the environment or a process step must be carried out under negative or positive pressure. The gap between the tube and the housing is ideally sealed with a gasket.

[0003] Because the pipes move due to the way they are used, the seals are subject to wear. Furthermore, the seals in metallurgical plants are exposed to high thermal stress. Seals or systems for sealing gaps in metallurgical plants are known from the prior art. EP 2 172 570 B1, Lance bushing for vacuum treatment plants, describes a compensator installed between the housing and the stuffing box guide tube. This compensator serves to compensate for both lateral and axial or rotational relative movements between a tube and a housing during the lance's movement.

[0004] DE 195 18 361 C1 discloses the use of a stuffing box with a thin-walled metal compensator to largely compensate for deviations in the parallelism between the lance axis and the slide track

[0005] The two proposed solutions require a complex structure of a seal in the form of a compensator and the corresponding components on the housing and pipe. Object of the invention:

[0006] The object of the invention is therefore to provide a simple and cost-effective alternative seal. Invention:

[0007] The object of the invention is achieved by a seal having the features of claim 1 and a system for sealing a gap having the features of claim 5.

[0008] A seal for sealing a gap between an opening in a housing part and a pipe which is movable in the axial and / or lateral direction and guided through the housing part has an inner contact surface for a positive or non-positive connection to the pipe and an outer contact surface for a positive or non-positive connection to the housing part. The seal consists of at least an outer body which is formed from at least two rings which are round or elliptical in cross-section and a circumferential web which connects each two rings to one another, and an inner body which connects the inner contact surface to the outer body, wherein the thickness of the body increases from the inner contact surface to the outer body. The inner and outer bodies are connected to one another in a non-positive, positive and / or materially bonded manner.

[0009] The increasing thickness allows the pipe to move without shifting relative to the seal. This prevents friction and maintains flexibility.

[0010] Further preferred embodiments of the invention are set forth in the dependent claims 2 to 4. The outer body is preferably made of a plastic material and is at least partially hollow. Furthermore, the outer body is designed to be inflated. This allows a seal to be inserted into a gap, and inflation generates a pressing force. Inaccuracies in the fit of the seal can thus be easily compensated.

[0011] The seal is preferably made at least partially of a plastic, preferably a silicone material, and the plastic preferably has a Shore A value of 30 to 90. The Shore A value is measured according to ASTM D 2240, version 2023. Plastic seals are lightweight, inexpensive to manufacture, and flexible.

[0012] The seal is preferably made at least partially of a graphite material, more preferably of an isostatically pressed graphite material. Graphite is a temperature-resistant material that exhibits sliding properties and is thermally stable. As a result, the moving pipe does not wear down the seal as quickly.

[0013] Furthermore, the object of the invention is achieved with a sealing system having the features of claim 5. At least two seals according to one of claims 1 to 4 are arranged in a gap between an opening in a housing part and a pipe that is movable in the axial and / or lateral direction and guided through the housing part. A multiple arrangement of seals in series reduces leakage losses and maintains mobility through the use of the seal according to the invention.

[0014] Further preferred embodiments of the sealing system are presented in the dependent claims 6 to 11.

[0015] In the gap, preferably at least three seals according to claim 4 are arranged at a distance of 5 mm to 10 mm and / or at least two seals according to one of claims 1 to 3.

[0016] A metal wiper ring is preferably arranged in the gap on the inside of the housing. If a pipe were to be pulled outward through the seal during maintenance, these deposits would wear down the seals. The metal wiper ring removes the contaminants adhering to the pipe and extends the service life of the seal.

[0017] The housing part is preferably a part of a metallurgical plant, preferably a cover of a vacuum treatment plant. Metallurgical plants in the sense of the invention can be metallurgical plants for iron and non-ferrous metal production.

[0018] Particular advantages arise in electric steel production based on feedstocks such as liquid steel or iron, scrap, DRI (Direct Reduced Iron), HBI (Hot Briquetted Iron) in various mixing ratios, and in non-ferrous production in metallurgical plants, preferably copper and aluminum production based on feedstocks such as liquid alloying and / or alloying of cathodes, ingots, scrap, or chips in various mixing ratios. A seal according to the invention can be easily applied, particularly in the sealing of electrodes, for example, in a ladle furnace.

[0019] The seal according to the invention can also be used to seal an electrode in a metallurgical plant for the production of TiO2-containing slag, for ferrochrome, ferromanganese, ferrosilicon and other ferroalloys as well as for non-ferrous slag processes by means of a reduction furnace.

[0020] The seal according to the invention can be used to seal the ram as well as to raise and lower the furnaces for heating the workpieces as well as for tools in the respective vacuum chambers in the sense of an isothermal forging process in a Hot Isothermal Forging (HIF) plant.

[0021] A seal according to the invention can be used for a plug in intermediate containers or in preheated and / or inductively and / or resistance-heated casting furnaces, for example in continuous casting plants, wherein vacuum and / or protective gas can be present on one side of the seal and protective gas / vacuum can be present on the other side.

[0022] In primary, secondary, and tertiary metallurgical plants, such as metal powder production plants, VOD plants, ESR, DESR, VESR, or other inert gas remelting plants, different tubes are installed in a metallurgical housing. The seal according to the invention can effectively separate the different gas zones from each other.

[0023] During the treatment of a molten metal in a metallurgical plant, the seals are exposed to high thermal stress and are therefore subject to corresponding wear. The seal according to the invention reduces wear and thus improves the availability of the plant.

[0024] The following three figures are attached to the description: Fig. 1: Single seal in section Fig. 2: Seal in top view Fig. 3: Sealing system

[0025] The invention is described in detail below with reference to the figures mentioned in the form of exemplary embodiments. In all figures, identical technical elements are designated by identical reference numerals.

[0026] The Fig. 1 shows a section through a seal 1 according to the invention. The seal 1 is formed from an inner and an outer body 14, 15, wherein the inner and outer bodies 14, 15 are positively connected to one another at the respective complementary surfaces 143, 151.

[0027] The outer body 14 is formed from two rings 141 with an elliptical cross-section, each of which has a cavity 144. The two rings 141 are connected to each other by a continuous web 142. The outer body 14 is made in one piece from a heat-resistant silicone material. The inner body 15 is made from an isostatically pressed graphite material.

[0028] Fig. 2 represents a one-piece seal made of a plastic. The plastic has a Shore A value of 30 to 90. Due to the flexibility of the plastic, the inflatable cavities in the rings 141 can be omitted.

[0029] Fig. 3 shows a possible sealing structure for a metallurgical plant, for example on a DESU plant, with an increased internal pressure p i > p u The gap 5 between a housing section of the housing part 2 and a pipe 3 is sealed by a series of different seals A, B. A scraper ring D is also attached to the inside of the housing part 2. This can be made of brass or bronze, for example. List of reference symbols: 1 seal 12 inner contact surface 13 outer contact surface 14 outer body 141 rings 142 jetty 143 complementary area 144 cavity 15 inner body 151 complementary area 2 Housing part 3 pipe 5 gap d distance A solid plastic seal B Seal silicone with cavity C Graphite seal D scraper ring QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 172 570 B1

[0003] DE 195 18 361 C1

[0004]

Claims

[1] Seal (1) for sealing a gap (5) between an opening in a housing part (2) and a pipe (3) which is movable in the axial and / or lateral direction and guided through the housing part, wherein the seal (1) has an inner contact surface (12) for positive or non-positive connection to the pipe (3) and an outer contact surface (13) for positive or non-positive connection to the housing part (2), characterized by , that - the seal (1) has an outer body (14) formed from at least two rings (141) of round or elliptical cross-section and a circumferential web (142) connecting two rings (141) to each other, and an inner body (15) connecting the inner contact surface (12) to the outer body (14), the thickness of the inner body (15) increasing from the inner contact surface (12) to the outer body (14); and - the inner and outer bodies (14, 15) are connected to one another in a force-fitting, form-fitting and / or material-fitting manner at mutually complementary surfaces (143, 151). [2] Seal according to claim 1, characterized by , that - the outer body (14) is made of a plastic material; and - the outer body (14) is at least partially hollow; and - the outer body (14) is arranged to inflate the cavities (144). [3] Seal (1) according to claim 1, characterized by , that - the seal (1) is at least partially made of a plastic, preferably of a silicone material; and - the plastic has a Shore A value of 30 to 90. [4] Seal (1) according to one of claims 1 to 3, characterized by that the seal (1) is at least partially made of a graphite material, preferably an isostatically pressed graphite material. [5] System for sealing a gap (5) between an opening in a housing part (2) and a pipe (3) which is movable in the axial and / or lateral direction and guided through the housing part, wherein at least two seals (1) according to one of claims 1 to 4 are arranged in the gap (5) between an opening in a housing part (2) and a pipe (3) which is movable in the axial and / or lateral direction and guided through the housing part (2). [6] System according to claim 5, characterized by , that - in the gap (5) at least three seals (1) according to claim 4 are arranged at a distance (d) of 5 mm to 10 mm and / or - at least two seals (1) according to one of claims 1 to 3 are arranged. [7] System according to claim 6, characterized by , that - a metallic scraper ring (6) is arranged in the gap (5) on an inner side of the housing part (2). [8] System according to one of claims 5 to 7, characterized by , that - the housing part (2) is a part of a metallurgical plant, preferably a cover of a vacuum treatment plant.

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