Magnetic powder liquid state injection method and system of magnetic powder sealing device

Abstract

The invention discloses a magnetic powder liquid state injection method and system for a magnetic powder sealing device, and the method comprises the steps: enabling a housing to sleeve a rotating shaft, and adjusting the relative position of the housing and the rotating shaft; sleeving the rotating shaft with a magnetic powder sealing assembly, and assembling the magnetic powder sealing assembly into the shell; magnetic powder and a volatile material are mixed to form a liquid-state magnetic powder dispersion liquid, and the magnetic powder dispersion liquid is injected into the sealing gap; and the magnetic powder dispersion liquid is heated, and the magnetic powder sealing assembly and the rotating shaft are driven to rotate relatively until the volatile materials in the magnetic powder dispersion liquid volatilize. According to the invention, the volatilizable material and the magnetic powder are mixed to improve the fluidity of the magnetic powder, so that the magnetic powder dispersion liquid is conveniently and uniformly injected into the sealing gap, then the volatilizable material is volatilized by heating, and finally the volatilizable material is converted into the uniformly distributed magnetic powder O-shaped ring, so that the safety and the reliability of magnetic powder sealing are guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of sealing, and in particular relates to a method and system for injecting liquid state magnetic powder into a magnetic powder sealing device. Background Art

[0002] Magnetic powder seal is a sealing form that uses magnetic particles as the main body and magnetic powder (hereinafter referred to as "magnetic powder") formed after surface lubricant and lubricant modification as the sealing medium. Compared with other sealing methods in related technologies, magnetic powder seal has a series of advantages such as low leakage rate, high pressure resistance, high and low temperature resistance, and high speed resistance, and plays an important role in many fields such as solid rocket engines and gas turbines.

[0003] In magnetic powder sealing applications, due to the poor fluidity of magnetic powder materials, the injection method used in related technologies often cannot form a uniform and complete sealing ring structure in the sealing gap, and cannot form a complete "O-type" sealing ring structure that can effectively provide sealing pressure resistance, which will affect the pressure resistance and leakage rate of the magnetic powder seal and even lose the sealing effect. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention provides a method for injecting magnetic powder in liquid state into a magnetic powder sealing device that can improve the uniformity of magnetic powder dispersion and has a good sealing effect.

[0006] An embodiment of the present invention further provides a magnetic powder liquid injection system.

[0007] A method for injecting magnetic powder in liquid state into a magnetic powder sealing device according to an embodiment of the present invention, the magnetic powder sealing device comprises a rotating shaft, a shell and a magnetic powder sealing assembly, the shell and the magnetic powder sealing assembly are sleeved on the rotating shaft and are rotatable relative to the rotating shaft, the magnetic powder sealing assembly comprises a pole shoe and a magnetic source, the magnetic source is connected to the pole shoe, and an annular sealing gap is provided between the pole shoe and the rotating shaft for filling magnetic powder;

[0008] The magnetic powder liquid injection method comprises:

[0009] S1, sleeve the housing on the rotating shaft, and adjust the relative position of the housing and the rotating shaft;

[0010] S2, sleeve the magnetic powder sealing assembly on the rotating shaft, and assemble the magnetic powder sealing assembly into the housing;

[0011] S3, mixing the magnetic powder and the volatile material to form a liquid magnetic powder dispersion, and injecting the magnetic powder dispersion into the sealing gap;

[0012] S4, heating the magnetic powder dispersion, and driving the magnetic powder sealing assembly and the rotating shaft to rotate relative to each other until the volatile material in the magnetic powder dispersion evaporates.

[0013] The embodiment of the present invention improves the fluidity of the magnetic powder by mixing the volatile material and the magnetic powder, thereby facilitating the uniform injection of the magnetic powder dispersion at the sealing gap, and then volatilizes the volatile material by heating, and finally converts it into a uniformly distributed magnetic powder O-ring, thereby ensuring the safety and reliability of the magnetic powder seal.

[0014] In some embodiments, the step of assembling the magnetic powder seal assembly into the housing includes:

[0015] A first end cover is connected to one end of the shell, the magnetic powder sealing assembly is introduced into the inner cavity of the shell from the end of the shell away from the first end cover, and the magnetic powder sealing assembly is abutted against the first end cover, and a second end cover is connected to the end of the shell away from the first end cover to fix the shell and the magnetic powder sealing assembly.

[0016] In some embodiments, a sealing component is disposed between the first end cover and the second end cover and the rotating shaft to seal the inner cavity of the housing, and a vent is disposed on the first end cover and the second end cover;

[0017] When the magnetic powder dispersion is heated in the step, safety gas is introduced into the inner cavity of the shell through some of the vents, and the safety gas carries the volatilized volatile materials and is discharged through other vents until the volatile materials are completely volatilized and there is no volatile material in the discharged safety gas.

[0018] In some embodiments, the magnetic powder liquid injection method further includes:

[0019] S5. Introduce safety gas into the inner cavity of the shell through at least some of the vents, close the other vents, and make the air pressure in the inner cavity of the shell reach a preset pressure threshold to compact the magnetic powder filled in the sealing gap.

[0020] In some embodiments, the safety gas is nitrogen.

[0021] In some embodiments, a heat transfer groove is arranged on the circumferential outer side of the pole shoe, and a medium inlet and a medium outlet corresponding to the heat transfer groove are arranged on the shell;

[0022] The step of heating the magnetic powder dispersion comprises:

[0023] A high-temperature medium is introduced into the heat transfer groove from the medium inlet, and the medium in the heat transfer groove is discharged from the medium outlet;

[0024] driving the rotating shaft to rotate;

[0025] The temperature in the inner cavity of the shell is obtained, the temperature is maintained to be not less than a preset temperature threshold, and the high temperature medium is stopped from being introduced into the heat transfer groove after the duration reaches a preset time threshold.

[0026] The magnetic powder liquid injection system of the embodiment of the present invention is used to inject magnetic powder into the sealing gap between the pole shoe and the rotating shaft in the magnetic powder sealing device, and the magnetic powder liquid injection system includes:

[0027] A first end cover and a second end cover, wherein the first end cover and the second end cover are used to be connected to a housing in the magnetic powder sealing device, and the first end cover and the second end cover are respectively connected to the housing at two ends of the axial direction of the rotating shaft to fix the magnetic powder sealing assembly in the magnetic powder sealing device;

[0028] An injection assembly, the injection assembly is used to mix magnetic powder and volatile material, and inject the liquid magnetic powder dispersion formed after the mixture into the sealing gap between the pole shoe and the rotating shaft in the magnetic powder sealing device;

[0029] A heating component is used to heat the liquid magnetic powder dispersion injected into the magnetic powder sealing device between the pole piece and the rotating shaft.

[0030] In some embodiments, the first end cover and the second end cover both have a threaded section, and the first end cover and the second end cover are connected to the shell through the threaded section, and sealing rings are provided on the end faces where the first end cover abuts against the shell and the end faces where the second end cover abuts against the shell.

[0031] In some embodiments, a sealing ring is provided on a wall surface of the first end cover corresponding to the rotating shaft and a wall surface of the second end cover corresponding to the rotating shaft, and a vent is provided on the first end cover and the second end cover;

[0032] The magnetic powder liquid injection system further comprises a gas supply assembly, and the gas supply assembly is used to be connected with at least a part of the vents to introduce safety gas into the inner cavity of the shell.

[0033] In some embodiments, a heat transfer groove is further included, wherein the heat transfer groove is opened on the circumferential side wall of the pole shoe in the magnetic powder sealing device, a heat transfer cavity is formed between the heat transfer groove and the shell, and the heating component is connected to the heat transfer cavity to pass a high-temperature medium into the heat transfer cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the state after the magnetic powder dispersion in the embodiment of the present invention is injected.

[0035] Figure 2Schematic diagram of the state of the magnetic powder dispersion after heating in an embodiment of the present invention.

[0036] Figure 3 Schematic diagram of the arrangement of the first end cover and the second end cover in an embodiment of the present invention.

[0037] Figure 4 Schematic diagram of the state change of the magnetic powder dispersion after heating in an embodiment of the present invention.

[0038] Reference numerals:

[0039] 1. Rotating shaft;

[0040] 2. Shell; 21. Medium inlet; 22. Medium outlet;

[0041] 31. First end cover; 32. Second end cover; 33. Vent;

[0042] 4. Pole shoe; 41. Heat transfer groove;

[0043] 5. Magnetic source;

[0044] 6. Magnetic isolation ring;

[0045] 7. Sealing ring;

[0046] 8. Magnetic powder. DETAILED DESCRIPTION

[0047] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0048] like Figure 1-Figure 4 As shown, a method for injecting magnetic powder in liquid state of a magnetic powder sealing device according to an embodiment of the present invention, wherein the magnetic powder sealing device comprises a rotating shaft 1, a housing 2 and a magnetic powder sealing assembly, wherein the housing 2 and the magnetic powder sealing assembly are sleeved on the rotating shaft 1 and are rotatable relative to the rotating shaft 1, and the magnetic powder sealing assembly comprises a pole shoe 4 and a magnetic source 5, wherein the magnetic source 5 is connected to the pole shoe 4, and an annular sealing gap is provided between the pole shoe 4 and the rotating shaft 1 for filling magnetic powder 8, as shown in FIG. Figure 1 As shown, the pole shoe 4 has a plurality of pole teeth, and an O-shaped magnetic powder sealing ring can be formed between each pole tooth and the rotating shaft 1. The magnetic source 5 can provide magnetic force to the pole shoe 4, so that the magnetic powder is stably dispersed in the sealing gap. After the magnetic powder sealing assembly is assembled to the housing 2, the relative positions of the magnetic powder sealing assembly, the housing 2 and the rotating shaft 1 can be stabilized, so as to facilitate the injection of magnetic powder.

[0049] The method for injecting magnetic powder in liquid state specifically includes:

[0050] S1. Sleeve the housing 2 on the rotating shaft 1, and adjust the relative position of the housing 2 and the rotating shaft 1. During assembly, the housing and the rotating shaft are usually aligned and fixed on the base device to achieve the fixation of the relative position of the two.

[0051] S2. Sleeve the magnetic powder sealing assembly on the rotating shaft 1, and assemble the magnetic powder sealing assembly into the shell 2. Specifically, the magnetic powder sealing assembly can be fixed by assembly parts such as connecting parts or limit parts arranged on the shell 2 to ensure that the assembly position of the magnetic powder sealing assembly on the shell 2 is determined. At this time, the relative position between the magnetic powder sealing assembly and the rotating shaft 1 is stable, which is convenient for the subsequent magnetic powder injection operation.

[0052] S3, the magnetic powder and the volatile material are mixed to form a liquid magnetic powder dispersion, and the magnetic powder dispersion is injected into the sealing gap. During normal assembly operations, the volatile material is in liquid state, and the volatile material can volatilize into gaseous state under high temperature environment. For example, the volatile material can be water, dichloromethane, ethanol, ether, etc. The volatile material is used as a liquid dispersant. After the volatile material and the magnetic powder are mixed and stirred, a liquid magnetic powder dispersion can be formed. Compared with pure magnetic powder, its fluidity can be improved, and it is also convenient to be evenly injected into the sealing gap during injection, and the dispersion is more uniform and consistent, and a complete O-shaped sealing ring is formed.

[0053] The magnetic powder and the volatile material can be mixed and stirred by arranging a stirring device, and the discharge end of the injection pipe is extended to the sealing gap by arranging an injection pipe and a pumping device, and the magnetic powder dispersion is pumped into the sealing gap through the injection pipe.

[0054] S4, heating the magnetic powder dispersion, and driving the magnetic powder sealing assembly and the rotating shaft 1 to rotate relative to each other until the volatile material in the magnetic powder dispersion evaporates. During the heating process, the volatile material is heated and evaporates into a gaseous state, while the magnetic powder remains in the sealing gap. Since the rotating shaft 1 rotates synchronously during the heating process, the liquid magnetic powder dispersion in the sealing gap can be continuously disturbed, thereby improving the uniformity of the magnetic powder O-ring finally converted, and ensuring the reliability of the magnetic powder seal.

[0055] When heating, the pole piece 4 or the shaft 1 can be heated to heat the inner cavity of the shell, and the heat can be transferred to the liquid magnetic powder dispersion. Alternatively, the volatilization of the volatile material can be achieved by changing the temperature of the environment in which the shaft 1, the shell 2 and the magnetic powder sealing assembly are located as a whole.

[0056] The embodiment of the present invention improves the fluidity of the magnetic powder by mixing the volatile material and the magnetic powder, thereby facilitating the uniform injection of the magnetic powder dispersion at the sealing gap, and then volatilizes the volatile material by heating, and finally converts it into a uniformly distributed magnetic powder O-ring, thereby ensuring the safety and reliability of the magnetic powder seal.

[0057] In some embodiments, the steps of assembling the magnetic powder seal assembly into the housing 2 include connecting the first end cap 31 at one end of the housing 2, feeding the magnetic powder seal assembly into the inner cavity of the housing 2 from the end of the housing 2 away from the first end cap 31, and making the magnetic powder seal assembly abut against the first end cap 31, and connecting the second end cap 32 at the end of the housing 2 away from the first end cap 31 to fix the housing 2 and the magnetic powder seal assembly. By assembling and connecting the first end cap 31 and the second end cap 32 on the housing 2, the first end cap 31 and the second end cap 32 are used to limit and clamp the magnetic seal assembly, so as to ensure accurate positioning of the magnetic seal assembly.

[0058] Furthermore, a sealing component is provided between the first end cover 31 and the second end cover 32 and the rotating shaft 1 to seal the inner cavity of the housing 2, and the sealing component is a rubber sealing ring 7. A vent 33 is provided on the first end cover 31 and the second end cover 32, and the number of vents 33 on the first end cover 31 and the second end cover 32 can be one or more; when the magnetic powder dispersion is heated in step S4, a safety gas is introduced into the inner cavity of the housing 2 through some of the vents 33, wherein the safety gas can be nitrogen. The safety gas carries the volatilized volatile material and is discharged through other vents 33 until the volatile material is completely volatilized and there is no volatile material in the discharged safety gas.

[0059] That is, when the magnetic powder dispersion is heated, the volatile material volatilizes into a gaseous state, and by introducing a safe gas into the inner cavity of the shell 2, the safe gas is used to replace the gas in the inner cavity of the shell 2, and the safe gas carrying the volatile material is discharged from the partial vent 33 and then led to a safe area for treatment before being discharged. In this embodiment, by safely discharging the gaseous volatile material, it can be applied to occasions with high requirements for the surrounding environment, avoiding the volatile material from being randomly scattered after heating, preventing pollution to the sealed inner cavity and the surrounding environment, and ensuring the normal operation of the equipment.

[0060] In application, safety gas can be introduced through some of the vents 33 of the first end cover 31, and the safety gas carrying volatile materials can be discharged through the other vents 33 of the first end cover 31; safety gas can be introduced through some of the vents 33 of the second end cover 32, and the safety gas carrying volatile materials can be discharged through the other vents 33 of the second end cover 32.

[0061] See also Figures 1 to 4 , another specific embodiment of the method for injecting magnetic powder liquid into the magnetic powder sealing device according to an embodiment of the present invention is described in detail.

[0062] The magnetic powder sealing device includes a rotating shaft 1, a shell 2 and a magnetic powder sealing assembly. The shell 2 and the magnetic powder sealing assembly are sleeved on the rotating shaft 1 and can rotate relative to the rotating shaft 1. The magnetic powder sealing assembly includes a pole shoe 4, a magnetic source 5 and a magnetic isolation ring 6. The number of pole shoes 4 is two. There is an annular sealing gap between the pole teeth of the pole shoe 4 and the rotating shaft 1 for filling magnetic powder. The magnetic source 5 is connected to the pole shoe 4, and the magnetic source 5 is arranged between the two pole shoes 4. The magnetic isolation ring 6 is arranged on the side of the pole shoe 4 away from the magnetic source 5 in the axial direction of the rotating shaft 1. The magnetic source 5 can provide magnetic force to the two pole shoes 4 at the same time, so that the magnetic powder is stably dispersed in the sealing gap. After the magnetic powder sealing assembly is assembled on the shell 2, the relative positions of the magnetic powder sealing assembly, the shell 2 and the rotating shaft 1 can be stabilized to facilitate the injection of magnetic powder.

[0063] In this embodiment, a sealing ring 7 is provided between the outer peripheral wall of the pole shoe 4 and the housing 2 to ensure sealing between the pole shoe 4 and the housing 2. A heat transfer groove 41 is arranged on the outer peripheral side of the pole shoe 4, and a medium inlet 21 and a medium outlet 22 corresponding to the heat transfer groove 41 are arranged on the housing 2, and the medium inlet 21 and the medium outlet 22 are connected to the heat transfer groove 41.

[0064] The method for injecting magnetic powder liquid into the magnetic powder sealing device specifically includes:

[0065] S1. Sleeve the housing 2 on the rotating shaft 1 and adjust the relative positions of the housing 2 and the rotating shaft 1.

[0066] S2. The magnetic powder sealing assembly is sleeved on the rotating shaft 1, and the magnetic powder sealing assembly is assembled into the housing 2. Specifically, a first end cap 31 is connected to one end of the housing 2, and the first end cap 31 is threadedly connected to the housing 2. According to the arrangement sequence of the magnetic isolation ring 6, the pole shoe 4 and the magnetic source 5 in the magnetic powder sealing assembly, the magnetic isolation ring 6 can be separately introduced into the inner cavity of the housing 2, and the pole shoe 4 and the magnetic source 5 can be connected together by magnetic force and then introduced into the inner cavity of the housing 2. For example, Figure 1 The arrangement of the magnetic powder sealing assembly shown in is a magnetic isolation ring 6, a pole shoe 4, a magnetic source 5, a pole shoe 4, and a magnetic isolation ring 6, and the assembly order is a magnetic isolation ring 6, a sealing structure composed of two pole shoes 4 and a magnetic source 5, and a magnetic isolation ring 6. When there are sealing grooves on the pole shoes, the housing, the first end cover, the second end cover body and other components, it is necessary to first arrange the sealing ring in the corresponding sealing groove so as to keep the inner cavity sealed after assembly. After assembling and installing in this order, the second end cover 32 is connected to the end of the housing 2 away from the first end cover 31 to fix the housing 2 and the magnetic powder sealing assembly. The second end cover 32 is also connected to the housing 2 by threads to ensure that the assembly position of the magnetic powder sealing assembly on the housing 2 is determined. At this time, the relative position between the magnetic powder sealing assembly and the rotating shaft 1 is stable, which is convenient for the subsequent magnetic powder injection operation.

[0067] S3, the magnetic powder and the volatile material are mixed to form a liquid magnetic powder dispersion, and the magnetic powder dispersion is injected into the sealing gap. During normal assembly operations, the volatile material is in a liquid state, and the volatile material can be volatilized into a gaseous state under a high temperature environment. For example, the volatile material can be water, methanol, etc. When the volatile material and the magnetic powder are mixed and stirred, a liquid magnetic powder dispersion can be formed. Compared with pure magnetic powder, its fluidity can be improved, and it is also convenient to be evenly injected into the sealing gap during injection, and the dispersion is more uniform and consistent, and a complete O-ring is formed.

[0068] S4, heating the magnetic powder dispersion, and driving the magnetic powder sealing assembly and the rotating shaft 1 to rotate relative to each other until the volatile material in the magnetic powder dispersion evaporates. Specifically, a high-temperature medium is introduced into the heat transfer groove 41 through the medium inlet 21 on the housing 2, and the medium in the heat transfer groove 41 is discharged through the medium outlet 22. The high-temperature medium can heat the pole shoe 4 and increase the temperature in the inner cavity. At this time, the volatile material in the magnetic powder dispersion will evaporate into a gaseous state due to the heat, and the magnetic powder will remain in the sealing gap. While heating, the rotating shaft 1 is driven to rotate to ensure that the magnetic powder dispersion is in a flowing state. In the process of continuous evaporation of the volatile material, the uniformity of the magnetic powder distribution is improved, and the uniformity and consistency of the magnetic powder O-ring finally converted are improved, thereby ensuring the reliability of the magnetic powder seal.

[0069] Furthermore, a sealing ring 7 is provided between the first end cover 31 and the second end cover 32 and the housing 2, and a sealing ring 7 is also provided between the first end cover 31 and the second end cover 32 and the rotating shaft 1, so that the inner cavity of the housing 2 is sealed, and the gaseous volatile material can be prevented from overflowing. One vent 33 can be provided on each of the first end cover 31 and the second end cover 32, or multiple vents 33 can be provided; while heating the magnetic powder dispersion, a safety gas is introduced into the inner cavity of the housing 2 through some of the vents 33, wherein the safety gas can be nitrogen, and the safety gas carries the volatilized volatile material and is discharged through other vents 33 until the volatile material is completely volatilized and there is no volatile material in the discharged safety gas.

[0070] The first end cover 31 and the second end cover 32 are used as tooling. After the magnetic powder injection is completed, the first end cover 31 and the second end cover 32 are removed. Of course, they can also be used as a component of the magnetic powder sealing device and are not removed, or only one of them is removed.

[0071] The embodiment of the present invention can control the heating time by detecting the temperature and gas in the shell 2. For example, by obtaining the temperature in the inner cavity of the shell 2, the temperature is kept not less than the preset temperature threshold, and the high-temperature medium is stopped from being introduced into the heat transfer groove 41 after the duration reaches the preset time threshold, so as to ensure that the volatile material is completely volatilized within the duration of the preset time threshold. For another example, by detecting whether the safety gas discharged from the inner cavity of the shell 2 carries the volatile material, when there is no volatile material in the safety gas, the heating can be stopped.

[0072] The preset temperature threshold is determined according to the temperature at which the volatile material is transformed from liquid to gas. The preset temperature threshold is 5 to 15 degrees Celsius higher than the temperature at which the volatile material is transformed from liquid to gas. The preset time threshold can be 10 to 45 minutes.

[0073] In this embodiment, by introducing safety gas into the inner cavity of the shell 2, the safety gas is used to replace the gas in the inner cavity of the shell 2, and the safety gas carrying volatile materials is discharged from the partial vent 33 and then led to a safe area for treatment before being discharged. The liquid state injection method of magnetic powder in the embodiment of the present invention can be applied to occasions with high requirements on the surrounding environment, avoiding the volatile materials from being randomly dispersed after heating, preventing pollution to the sealed inner cavity and the surrounding environment, and ensuring the normal operation of the equipment.

[0074] In application, safety gas can be introduced into the inner cavity of the shell 2 through the vent 33 on the first end cover 31, and the safety gas carrying volatile materials can be discharged through the vent 33 on the second end cover 32. Alternatively, safety gas can be introduced through some of the vents 33 on the first end cover 31, and the safety gas carrying volatile materials can be discharged through the other vents 33 of the first end cover 31, while safety gas can be introduced through some of the vents 33 on the second end cover 32, and the safety gas carrying volatile materials can be discharged through the other vents 33 on the second end cover 32.

[0075] S5. After the volatile material is exhausted, safe gas is introduced into the inner cavity of the shell 2 through at least part of the vents 33, and other vents 33 are closed, so that the air pressure in the inner cavity of the shell 2 reaches a preset pressure threshold to compact the magnetic powder filled in the sealed gap.

[0076] Compared with the injection method in the related art, the embodiment of the present invention disperses the sealed magnetic powder with poor fluidity and difficult to distribute stably into the volatile material to form a magnetic powder dispersion with good fluidity, and injects it into the pole teeth of the pole shoe 4, so that the magnetic powder can be evenly distributed along the circumference of the rotating shaft 1, and further heats the inner cavity of the shell 2 through the heat transfer groove 41 of the pole shoe 4. At the same time, the rotating shaft 1 keeps rotating, and the volatile material in the magnetic powder dispersion will continue to evaporate, and the evenly distributed magnetic powder dispersion O-ring will eventually be converted into an evenly distributed magnetic powder O-ring. The embodiment of the present invention also introduces safety gas to bring the volatile material out of the sealed inner cavity, thereby ensuring the safety and reliability of the magnetic powder seal. Furthermore, by increasing the pressure of the safety gas, the magnetic powder in the sealing gap can be compacted, and the air between the magnetic powder particles can be squeezed out, thereby improving the density of the sealed magnetic powder, effectively reducing the sealing leakage rate, and ensuring the reliability of the magnetic powder seal.

[0077] The embodiment of the present invention avoids the problem of uneven magnetic powder distribution and large porosity caused by direct injection of magnetic powder, effectively improves the pressure resistance of the magnetic powder seal, and reduces the leakage rate of the magnetic powder seal.

[0078] The following describes a magnetic powder liquid injection system according to an embodiment of the present invention, which is used to inject magnetic powder into the sealing gap between the pole teeth of the pole shoe 4 and the rotating shaft 1 in the magnetic powder sealing device. The magnetic powder liquid injection system includes a first end cover 31, a second end cover 32, an injection assembly, a heating assembly and an air supply assembly.

[0079] The first end cover 31 and the second end cover 32 are used to connect with the shell 2 in the magnetic powder sealing device, and the first end cover 31 and the second end cover 32 are respectively connected to the two ends of the shell 2 in the axial direction of the rotating shaft 1 to fix the magnetic powder sealing assembly in the magnetic powder sealing device; the first end cover and the second end cover both have threaded sections, and the first end cover 31 and the second end cover 32 are both threadedly connected with the shell 2 through the threaded sections, and sealing rings are provided on the end surfaces abutting against the shell and the end surfaces abutting against the shell, and sealing rings are provided on the wall surfaces corresponding to the first end cover and the rotating shaft and the wall surfaces corresponding to the second end cover and the rotating shaft. In other words, a sealing ring 7 is provided between the first end cover 31 and the shell 2 and between the second end cover 32 and the shell 2, and a sealing ring 7 is provided between the first end cover 31 and the second end cover 32 and the rotating shaft 1, so that the inner cavity of the shell 2 can be sealed, so that the magnetic powder sealing assembly is in the sealed inner cavity.

[0080] The injection assembly is used to mix magnetic powder and volatile material, and inject the liquid magnetic powder dispersion formed after the mixture into the sealing gap between the pole teeth of the pole shoe 4 and the rotating shaft 1 in the magnetic powder sealing device.

[0081] The heating component is used to heat the liquid magnetic powder dispersion injected into the pole teeth of the pole shoe 4 in the magnetic powder sealing device and the rotating shaft 1. A heat transfer groove 41 is opened on the circumferential side wall of the pole shoe 4 in the magnetic powder sealing device, and a heat transfer cavity is formed between the heat transfer groove 41 and the shell 2. The heating component is connected to the heat transfer cavity to pass a high-temperature medium into the heat transfer cavity, thereby increasing the temperature in the inner cavity of the shell 2.

[0082] The first end cover 31 and the second end cover 32 are provided with air vents 33, and the air supply assembly is used to be connected to at least part of the air vents 33 to introduce safety gas into the inner cavity of the shell 2. The safety gas can carry volatile materials in gaseous state and can also improve the density of magnetic powder by adjusting the air pressure in the inner cavity.

[0083] The magnetic powder liquid injection system in the embodiment of the present invention can be used to implement the magnetic powder liquid injection method of the magnetic powder sealing device in the above embodiment, and the beneficial effects that can be achieved by the magnetic powder liquid injection system in the embodiment of the present invention are the same as the beneficial effects achieved by the magnetic powder liquid injection method of the magnetic powder sealing device in the above embodiment, so they are not repeated here.

[0084] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0085] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0086] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0087] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0088] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0089] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for injecting liquid magnetic powder into a magnetic powder sealing device, characterized in that: The magnetic powder sealing device comprises a rotating shaft, a shell and a magnetic powder sealing assembly, wherein the shell and the magnetic powder sealing assembly are sleeved on the rotating shaft and are rotatable relative to the rotating shaft, and the magnetic powder sealing assembly comprises a pole shoe and a magnetic source, wherein the magnetic source is connected to the pole shoe, and an annular sealing gap is provided between the pole shoe and the rotating shaft for filling magnetic powder; The magnetic powder liquid injection method comprises: S1, sleeve the housing on the rotating shaft, and adjust the relative position of the housing and the rotating shaft; S2, sleeve the magnetic powder sealing assembly on the rotating shaft, and assemble the magnetic powder sealing assembly into the housing; S3, mixing the magnetic powder and the volatile material to form a liquid magnetic powder dispersion, and injecting the magnetic powder dispersion into the sealing gap; S4, heating the magnetic powder dispersion, and driving the magnetic powder sealing assembly and the rotating shaft to rotate relative to each other until the volatile material in the magnetic powder dispersion evaporates.

2. The method for injecting liquid magnetic powder into a magnetic powder sealing device according to claim 1, characterized in that: The step of assembling the magnetic powder seal assembly into the housing comprises: A first end cover is connected to one end of the shell, the magnetic powder sealing assembly is introduced into the inner cavity of the shell from the end of the shell away from the first end cover, and the magnetic powder sealing assembly is abutted against the first end cover, and a second end cover is connected to the end of the shell away from the first end cover to fix the shell and the magnetic powder sealing assembly.

3. The method for injecting liquid magnetic powder into a magnetic powder sealing device according to claim 2, characterized in that: A sealing component is disposed between the first end cover and the second end cover and the rotating shaft to seal the inner cavity of the housing, and a vent is disposed on the first end cover and the second end cover; When the magnetic powder dispersion is heated in the step, safety gas is introduced into the inner cavity of the shell through some of the vents, and the safety gas carries the volatilized volatile materials and is discharged through other vents until the volatile materials are completely volatilized and there is no volatile material in the discharged safety gas.

4. The method for injecting liquid magnetic powder into a magnetic powder sealing device according to claim 3, characterized in that: The magnetic powder liquid injection method also includes: S5. Introduce safety gas into the inner cavity of the shell through at least some of the vents, close the other vents, and make the air pressure in the inner cavity of the shell reach a preset pressure threshold to compact the magnetic powder filled in the sealing gap.

5. The method for injecting liquid magnetic powder into a magnetic powder sealing device according to claim 3, characterized in that: The safety gas is nitrogen.

6. The method for injecting liquid magnetic powder into a magnetic powder sealing device according to any one of claims 1 to 5, characterized in that: A heat transfer groove is arranged on the circumferential outer side of the pole shoe, and a medium inlet and a medium outlet corresponding to the heat transfer groove are arranged on the shell; The step of heating the magnetic powder dispersion comprises: A high-temperature medium is introduced into the heat transfer groove from the medium inlet, and the medium in the heat transfer groove is discharged from the medium outlet; driving the rotating shaft to rotate; The temperature in the inner cavity of the shell is obtained, the temperature is maintained to be not less than a preset temperature threshold, and the high temperature medium is stopped from being introduced into the heat transfer groove after the duration reaches a preset time threshold.

7. A magnetic powder liquid injection system, characterized in that: Used to inject magnetic powder into the sealing gap between the pole shoe and the rotating shaft in the magnetic powder sealing device, the magnetic powder liquid injection system comprises: A first end cover and a second end cover, wherein the first end cover and the second end cover are used to be connected to a housing in the magnetic powder sealing device, and the first end cover and the second end cover are respectively connected to the housing at two ends of the axial direction of the rotating shaft to fix the magnetic powder sealing assembly in the magnetic powder sealing device; An injection assembly, the injection assembly is used to mix magnetic powder and volatile material, and inject the liquid magnetic powder dispersion formed after the mixture into the sealing gap between the pole shoe and the rotating shaft in the magnetic powder sealing device; A heating component is used to heat the liquid magnetic powder dispersion injected into the magnetic powder sealing device between the pole piece and the rotating shaft.

8. The magnetic powder liquid injection system according to claim 7, characterized in that: The first end cover and the second end cover both have threaded sections, and the first end cover and the second end cover are connected to the shell through the threaded sections. Sealing rings are provided on the end surfaces where the first end cover abuts against the shell and the end surfaces where the second end cover abuts against the shell.

9. The magnetic powder liquid injection system according to claim 8, characterized in that: A sealing ring is provided on the wall surface of the first end cover corresponding to the rotating shaft and on the wall surface of the second end cover corresponding to the rotating shaft, and a vent is provided on the first end cover and the second end cover; The magnetic powder liquid injection system further comprises a gas supply assembly, and the gas supply assembly is used to be connected with at least a part of the vents to introduce safety gas into the inner cavity of the shell.

10. The magnetic powder liquid injection system according to claim 7, characterized in that: It also includes a heat transfer groove, which is opened on the circumferential side wall of the pole shoe in the magnetic powder sealing device, a heat transfer cavity is formed between the heat transfer groove and the shell, and the heating component is connected to the heat transfer cavity to pass a high-temperature medium into the heat transfer cavity.

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