Damped solid body

Abstract

The invention relates to an arrangement (10) for separating two media having an inner wall (50) and an outer wall (51). At least one space (52) is formed between the inner and outer walls (50, 51). A material (53) is integrated in the space (52).

Description

[0001] Damped solid body

[0002] The invention relates to an arrangement for separating two media with an inner and an outer wall, wherein at least one space is formed between the inner and outer walls.

[0003] The arrangement is used to separate two media, for example different fluids, when used in centrifugal pumps and / or in valves.

[0004] Centrifugal pumps are based on the principle of energy transfer to a fluid through a change in angular momentum caused by a torque generated by a uniformly rotating impeller on the fluid flowing through it. Centrifugal pumps usually have a spiral-shaped casing in which a bladed impeller rotates at high speed.

[0005] A magnetic-drive pump has such a device for separating two media and is a sealless centrifugal pump in which the drive shaft torque is transmitted by magnetic forces with a permanent magnetic coupling. The magnetic coupling consists of an outer rotor rigidly connected to the motor shaft and an inner rotor connected to the pump shaft. Both rotors are equipped with permanent magnets so that opposite poles face each other. When the outer rotor is driven, the inner rotor rotates synchronously, thus rotating the pump impeller. By installing a separation device in the gap between the outer and inner rotors, the so-called containment shell, complete sealing is achieved.

[0006] By using a containment shell between the primary and secondary parts, a seal is created between these components, preventing liquids or gases, for example, from passing from the secondary side to the primary side. This is particularly crucial when the magnetic coupling is used in a pump, for example. In this case, the pump impeller and the secondary part of the magnetic coupling are mounted on a common shaft, while the primary part is connected to a motor shaft. Depending on the pump's pumped medium, it is then necessary to prevent this medium from passing through the containment shell towards the primary part or towards the motor.

[0007] Due to malfunctions or malfunctions, it is possible, on the one hand, that the primary part and / or the secondary part directly damage the containment shell. On the other hand, damage to the containment shell can be caused directly by magnetic or non-magnetic solids in the pumped medium. However, this damage is difficult to detect during operation. For this reason, double-walled containment shells have proven to be effective in practice. A gap is arranged between the walls. This gap is continuously monitored using sensors, allowing damage to the containment shell to be detected.

[0008] WO 2020 / 212250 A1 discloses a containment shell for a magnetic coupling with a cylindrical shell region and a base region adjoining a first end of the shell region, wherein at least the shell region has an inner wall and an outer wall surrounding the inner wall, wherein the inner wall and the outer wall are spaced apart from one another in the radial direction by a gap. According to the invention, the inner wall is integrally connected to the outer wall via a plurality of webs. According to the invention, the leakage of the containment shell can be determined by monitoring the inner gap using a control medium. A valve refers to a component for changing and controlling material flows, which is used in particular in pipelines and containers for fluids.

[0009] A bellows is an elastic, accordion-like folding tube that is attached over mechanically interlocking machine parts to protect them from external influences, especially contamination, and to seal them off from the environment.

[0010] In valves used in the chemical industry, bellows are used to hermetically seal moving valve components against stationary components.

[0011] It is already known to produce assemblies for separating two media using an additive manufacturing process. In additive manufacturing, a component is created by adding material. A special feature of generative manufacturing processes is that the production process is tool-free and takes place directly based on 3D CAD data, without the use of molds. This increases production flexibility compared to conventional manufacturing processes. Furthermore, particularly delicate and complex components can be produced.

[0012] However, the disadvantage of additively manufactured components is that they have significantly lower damping and significantly lower thermal conduction compared to components produced using conventional manufacturing processes.

[0013] In addition, a new European safety directive requires additional protection of safety-relevant components.

[0014] The object of the invention is to provide an arrangement for separating two media that is characterized by improved damping and improved heat conduction. Furthermore, the arrangement for separating two media should meet current safety requirements. Furthermore, the arrangement should be characterized by a compact design. The arrangement should be simple and cost-effective to implement.

[0015] This object is achieved according to the invention by an arrangement for separating two media. Preferred variants can be found in the independent main claims, the subclaims, the description, and the drawings.

[0016] According to the invention, a material is integrated into the space.

[0017] A room is defined by the three mutually orthogonal dimensions of length, width, and height. It defines a spatial volume through its walls and thus forms a geometric body.

[0018] At least one space of the arrangement is formed between the inner and outer walls. In the simplest embodiment of the invention, only one space exists between the walls of the arrangement. This space can extend completely between the walls or only in a small area of ​​the walls.

[0019] Alternatively, two and / or more and / or a plurality of spaces can be formed between the walls of the arrangements, extending side by side and / or parallel. These spaces can have connections or be designed without any connections. Such connections can preferably be designed in the form of a passage.

[0020] In the narrower sense of materials, materials are substances in the solid state from which components and structures can be made.

[0021] The material can preferably be in granular, powdery, granulated, or particulate form. Ideally, the material is designed as a free-flowing material. For this purpose, the material can be designed as a free-flowing bulk material or fines.

[0022] Flowability refers to the ability of bulk solids or fines to flow vertically under defined conditions. The flowability of a bulk solid is determined by its composition and the nature of its particles. Influencing factors include grain size, grain size distribution, surface texture of the grains, and adhering moisture.

[0023] Flowability is often specified as the flow time of a specified sample volume from defined funnels. The corresponding procedures are standardized: ISO 6186 defines the flow time as the flow time in seconds. ISO 4490, ASTM B213, ASTM B855, and ASTM B964 define the flow time as the flow time in seconds or s / 20 cm. 3 .

[0024] In an advantageous variant of the invention, the material is in the form of agglomerated particles.

[0025] Ideally, the space is filled with at least 10%, preferably at least 20%, in particular at least 30%, of material and / or less than 90%, preferably less than 80%, in particular less than 70%, of material.

[0026] "Integrated" refers to the process of combining into a single, unified whole. The material is incorporated into a single, unified whole, the arrangement used to separate two fluids.

[0027] Ideally, the material is integrated and / or incorporated into a larger whole, particularly into the space of the arrangement. Preferably, the material is positively integrated into at least one space of the arrangement. This positive integration is created by the material being interlocked within the space. This prevents the material from leaving the space. Furthermore, the material cannot be subsequently inserted into the space.

[0028] Advantageously, the material is permanently installed in the space. This means that it cannot be subsequently added or removed from the space.

[0029] In a particularly preferred variant of the invention, the material in the chamber and the material of the walls are made of the same material, in particular identical. The walls of the chamber and the material itself are thus made of a single material.

[0030] Preferably, the inner wall is formed integrally with the outer wall. This also results in the arrangement for separating two fluids being completely integral.

[0031] In a particularly advantageous variant of the invention, at least one sensor is arranged in the room.

[0032] Such a sensor can be implemented in the form of a monitoring sensor designed to detect damage to the inner and / or outer wall. The sensor can preferably detect the dew point, temperature, oxygen content, pressure, and / or conductivity in the room and / or a control medium in the room.

[0033] If the dew point is monitored, the monitoring sensor is a dew point sensor that continuously monitors the dew point of a liquid control medium. If a wall is damaged, a fluid can penetrate the space and mix with the control medium. This leads to a change in the dew point. Alternatively, the space can be filled with a gaseous control medium, e.g., argon or another inert gas, with the sensor designed as an oxygen sensor. If, for example, an oxygen-containing fluid penetrates the space, the oxygen content changes, and the sensor signal can be used to generate an alarm.

[0034] Regardless of the sensor design, the control medium is preferably a non-reactive fluid.

[0035] The advantageous monitoring of the room with at least one sensor provides additional safeguards for the operation of safety-relevant components. With appropriate integration of the sensor into a higher-level monitoring system or process control system, the requirement of a "second line of defense" under current safety guidelines can be met without having to additionally encapsulate the safety-relevant components.

[0036] In another design variant, the chamber is fluid-free and / or gas-free. Alternatively, the chamber can also be vacuum-sealed.

[0037] When the arrangement is designed as a containment shell or as a bellows, the space can extend in the circumferential direction of the arrangement.

[0038] In a favorable embodiment of the invention, separating webs are arranged in the circumferential direction between the inner and outer walls and extend in the longitudinal direction. The longitudinal direction in this context refers to the direction parallel to the casing region of the arrangement. The number and spacing of the webs can, for example, be the result of mechanical and thermal optimization to reduce eddy current losses. However, the invention also encompasses further, alternative design variants of the separating webs. For example, a spiral design, an arcuate design, and penetration of spaces arranged longitudinally and circumferentially are also possible. Furthermore, the individual alternatives can also be combined with one another.By using, on the one hand, dividers that extend in the longitudinal direction and, on the other hand, dividers that extend in the circumferential direction, a grid-like arrangement of webs can be achieved in the room.

[0039] In a particularly advantageous variant of the invention, the material is integrated into the space, while the space is formed by a single-piece wall. This preferably occurs during the additive manufacturing of the arrangement. For example, in selective laser melting or powder bed processes, the space is formed from a powdered material by selectively melting the powder. However, in contrast to the otherwise meticulous removal of excess powder, the excess powder is left in place. This ensures that the excess material is integrally enclosed in the space during the formation of the space.

[0040] According to the invention, in the method for producing an arrangement, the material is integrated into the space, while the inner and outer walls are produced by selectively acting on the material with radiation.

[0041] Ideally, the assembly for separating two fluids is manufactured using additive manufacturing. Additive manufacturing makes it possible to realize the complex design of the assembly with material integrated into the space. Furthermore, customized, one-off versions of the assembly can be produced extremely quickly and as needed.

[0042] An arrangement for separating two fluids was created using an additive manufacturing process. The term additive manufacturing encompasses all manufacturing processes in which material is applied layer by layer, thus creating three-dimensional, one-piece walls and at least one chamber. The layer-by-layer construction is computer-controlled from one or more liquid or solid materials according to specified dimensions and shapes. Physical or chemical curing or melting processes take place during construction. Typical materials for 3D printing are plastics, synthetic resins, ceramics, metals, carbon, and graphite materials.

[0043] Selective laser melting and cladding, also known as build-up welding, are particularly used to form the assembly. In an alternative variant of the invention, extrusion combined with the application of meltable plastic is also a suitable process.

[0044] In selective laser melting, the arrangement for separating two fluids is manufactured using a process in which a layer of a building material is first applied to a base. The building material for producing the arrangement is preferably metallic powder particles. In one variant of the invention, iron-containing and / or cobalt-containing powder particles are used for this purpose. These can contain additives such as chromium, molybdenum or nickel. The metallic building material is applied in powder form in a thin layer to a plate. The powdered material is then completely melted locally at the desired locations using radiation, and after solidification, a solid layer of material forms. The base is then lowered by the amount of one layer thickness and more powder is applied.This cycle is repeated until all layers are produced and the finished assembly is created. The excess powder remains in the assembly space, allowing new, unique properties to be realized.

[0045] A laser beam, for example, can be used as the radiation source to generate the assembly from the individual powder layers. The data for guiding the laser beam is generated using software based on a 3D CAD model. As an alternative to selective laser melting, an electron beam (EBN) can also be used. Cladding, or overlay welding, produces the assembly using a process that coats a starting piece by welding. Cladding builds up a volume using a filler material in the form of a wire or powder, creating a particularly delicate and optimized shape for the assembly.

[0046] The material integrated into the space created between the inner and outer walls of the assembly achieves special properties that are important for technical applications. For example, the assembly exhibits significantly improved thermal conductivity due to the integration of the material into the space. This allows for better dissipation of the heat generated by eddy current losses when used as a containment shell in magnetically driven centrifugal pumps.

[0047] The material-filled space of the arrangement also leads to increased damping of the component, very similar to that of gray cast iron. This allows for excellent absorption of vibrations that occur, for example, during the operation of a centrifugal pump.

[0048] The arrangement for separating two fluids also has improved pressure resistance, which can be achieved by the space filled with material.

[0049] Furthermore, by keeping the material in the assembly space, it is no longer necessary to remove it. This typically requires removing the component from the additive manufacturing machine and cleaning it manually. This leads to an increase in production speed.

[0050] The integration of the material into the space of the arrangement for separating two fluids leads to a beneficial improvement in the mechanical and thermal properties while simultaneously increasing the production speed.

[0051] The arrangement for separating two fluids with an inner and an outer wall forming a space into which a material is integrated is used to improve damping and / or to improve heat conduction in static fluid separation devices, in particular in containment shells of centrifugal pumps, as well as in bellows of valves.

[0052] Furthermore, the arrangement of one or more sensors monitoring the functionality of the assembly provides additional protection, as required by modern safety regulations. The monitored space of the assembly thus provides a "second line of defense" and avoids the need for a second encapsulation of containment shells or bellows.

[0053] Further features and advantages of the invention will become apparent from the description of embodiments with reference to the drawings and from the drawings themselves.

[0054] It shows:

[0055] Fig. 1 is a sectional view of a magnetic coupling pump,

[0056] Fig. 2 a sectional view of a bellows fitting,

[0057] Fig. 3 is a detailed view of a room according to the invention,

[0058] Fig. 4 shows another design variant of the room,

[0059] Fig. 5 an alternative design of the room.

[0060] Fig. 1 shows a pump 1 in the form of a magnetic drive pump. The pump 1 has a multi-part pump housing 2 of a centrifugal pump, which comprises a hydraulic housing 3 designed as a spiral housing, a housing cover 4, a bearing support lantern 5, a bearing support 6 and a bearing cover 7. The hydraulic housing 3 has an inlet opening 8 for sucking in a pumped medium and an outlet opening 9 for expelling the pumped medium. The housing cover 4 is arranged on the side of the hydraulic housing 3 opposite the inlet opening 8. The bearing support lantern 5 is fastened to the side of the housing cover 4 facing away from the hydraulic housing 3. The bearing support 6 is attached to the side of the bearing support lantern 5 opposite the housing cover 4. The bearing cover 7 is in turn fastened to the side of the bearing support 6 facing away from the bearing support lantern 5.

[0061] An arrangement for separating two fluids 10, which in the illustrated embodiment is designed as a containment shell, is attached to the side of the housing cover 4 facing away from the hydraulic housing 3 and extends at least partially through an interior space 11 defined by the pump housing 2, in particular by the housing cover 4, by the bearing support lantern 5, and by the bearing support 6. The arrangement 10 hermetically seals a chamber 12 enclosed by it and the housing cover 4 from the interior space 11.

[0062] A rotatable impeller shaft 13 extends from a flow chamber 14 defined by the hydraulic housing 3 and the housing cover 4 through an opening 15 provided in the housing cover 4 into the chamber 12. An impeller 16 is attached to a shaft end of the impeller shaft 13 located within the flow chamber 14. At the opposite shaft end, which has two shaft sections 13a, 13b, each with increasing diameters, an inner rotor 17 is arranged within the chamber 12. The inner rotor 17 is equipped with several magnets 18, which are arranged on the side of the inner rotor 17 facing the containment shell 10. An auxiliary impeller 20 is attached to the inner rotor 17 by means of screws 19 or other suitable fastening means.

[0063] A bearing arrangement 21 is arranged between the impeller 16 and the inner rotor 17 and is operatively connected to the rotatably driven impeller shaft 13. A drive motor (not shown), preferably an electric motor, drives a drive shaft 22. The drivable drive shaft 22 is arranged essentially coaxially with the impeller shaft 13. The drive shaft 22 extends through the bearing cover 7, the bearing carrier 6 and at least partially into the bearing carrier lantern 5. The drive shaft 22 is mounted in two ball bearings 23, 24 accommodated in the bearing carrier 6. An outer rotor 26 carrying a plurality of magnets 25 is arranged at the free end of the drive shaft 22. The magnets 25 are arranged on the side of the outer rotor 26 facing the arrangement 10.The outer rotor 26 extends at least partially over the arrangement 10 and interacts with the inner rotor 17 in such a way that the rotating outer rotor 26, by means of magnetic forces, also sets the inner rotor 17 and thus the impeller shaft 13 and the impeller 16 into a rotational movement.

[0064] Fig. 2 shows a sectional view of a bellows-sealed valve 27. The fluid flows through the valve body 30 from the inlet flange 28 toward the outlet flange 29. The valve half-cone 32 can engage the valve seat to seal off the fluid flow. The valve half-cone 32 is rotationally fixedly connected to the valve spindle 33, which can be moved via the handwheel 34 using the valve superstructure 35.

[0065] The passage of the valve spindle 35 through the valve assembly 36 is sealed by the assembly 10 for separating two fluids. In the illustrated embodiment, the assembly 10 is designed as a bellows. The valve assembly 36 is connected to the valve body 30 by the fixing elements 38 and sealed against fluid leakage by the sealing element 37.

[0066] Fig. 3 shows a detailed representation of a space 52 according to the invention as a section of an arrangement 10 for separating two fluids. The section shown shows three different configurations of the space 52. The space 52 is formed by the inner wall 50 and the outer wall 51, with the outer wall 51 having a sinusoidal shape. The separating webs 56 are arranged in the circumferential direction between the inner wall 50 and the outer wall 51 and extend in the longitudinal direction. The longitudinal direction in this context refers to the direction parallel to the casing region of the arrangement 10. As a result, the space 52 extends spirally with a slight pitch in the circumferential direction of the arrangement 10.

[0067] A material 53 is integrated into space 52. Material 53 is embodied as a free-flowing powder that remained in the space during the integral formation of the inner wall 50 and the outer wall 51 using selective laser melting. Material 53, as well as the inner wall 50 and the outer wall 51, are made of the same material.

[0068] To achieve particularly high thermal conductivity and a particularly high damping effect, the chamber 52 can be filled with a complete bed 57 of the material 53. The complete bed 57 corresponds to a filling of up to 90%.

[0069] In a further embodiment, the space 52 can also be filled with agglomerated particles 54.

[0070] Fig. 4 shows a further section of the arrangement 10 in a variant of the chamber 52. Fig. 4 largely corresponds to Fig. 3. Here, the outer wall 51 has a trapezoidal shape, so that the chamber 52 has a triangular cross-section. The material 53, which in Fig. 4 is in the form of agglomerated particles 54, is integrated into the chamber 52.

[0071] The material 53 remained in space 52 during additive manufacturing and was not meticulously removed, as is usually the case. In the variant shown, some particles of the material 53 were formed into agglomerated particles 54 with the help of energy input in order to achieve desired properties with regard to thermal conduction and damping. The material 53 is thus positively integrated into space 52 and could not be subsequently inserted. Fig. 5 shows an alternative embodiment of space 52 in a detail view of the arrangement 10. In this embodiment, the outer wall 51 is particularly flat and designed without any elevations or separating webs 56. The material 53 is integrated into space 52 as a free-flowing fill. In addition, the space 52 has a sensor 55, which in this embodiment is designed as a conductivity sensor. This allows the integrity of the arrangement 10 to be continuously monitored.In the event of damage, an evaluation unit coupled to the sensor can trigger an alarm.

Claims

Patent claims 1. Arrangement (10) for separating two media with an inner wall (50) and an outer wall (51) wherein at least one space (52) is formed between the inner and outer wall (50, 51), characterized in that a material (53) is integrated in the space (52).

2. Arrangement according to claim 1, characterized in that the material (53) is designed as a free-flowing material.

3. Arrangement according to claim 1 or 2, characterized in that the material (53) in the space (52) and the material of the walls (50, 51) are made of the same material (53).

4. Arrangement according to one of claims 1 to 3, characterized in that the inner wall (50) is formed integrally with the outer wall (51).

5. Arrangement according to one of claims 1 to 4, characterized in that material (53) is integrated into the space (52), while the space (52) is formed by a one-piece wall (50, 51).

6. Arrangement according to one of claims 1 to 5, characterized in that the material (53) is positively integrated into the space (52). An arrangement according to any one of claims 1 to 6, characterized in that the material (53) is in the form of agglomerated particles (54). An arrangement according to any one of claims 1 to 7, characterized in that the space (52) is filled with at least 10%, preferably at least 20%, and in particular at least 30%, of material (53) and / or with less than 90%, preferably less than 80%, and in particular less than 70%, of material (53). An arrangement according to any one of claims 1 to 8, characterized in that at least one sensor (55) is arranged in the space (52). An arrangement according to any one of claims 1 to 9, characterized in that the space (52) is fluid-free and / or gas-free. An arrangement according to any one of claims 1 to 10, characterized in that the space (52) extends in the circumferential direction of the arrangement (10).A method for manufacturing an arrangement (10), characterized in that the material (53) is integrated into the space (52), while the inner and outer walls (50, 51) are generated by selectively applying radiation to the material (53). The arrangement (10) with an inner and outer wall (50, 51) forming a space (52) into which a material (53) is integrated is used to improve damping and / or thermal conductivity.

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