Apparatus for sealing drive shaft

Abstract

The present invention discloses a rotating shaft sealing device installed between a blower comprising a drive shaft rotated by a drive motor, an impeller connected to the drive shaft by an axial coupling and rotating, and a casing housing the impeller, the device comprising: a sleeve fixed to the outer surface of the drive shaft via a packing; a seal housing covering the outer surface of the sleeve and having a plurality of sealing grooves arranged along the longitudinal direction of the drive shaft on its inner surface; a plurality of seals arranged along the longitudinal direction of the drive shaft and an annular garter spring inserted into a spring groove on the outer surface of the seal to support the annular spacing between the segments of the seals and the plurality of seals arranged along the longitudinal direction of the drive shaft, the seal housing being divided into several segments to expand radially between the sleeve and the seal housing.

Description

Technology Field

[0001] The present invention relates to a sealing device for a drive shaft used for the purpose of transmitting power while the shaft rotates directly, and more specifically, to a rotating shaft sealing device for preventing leakage of process fluids such as air, steam, or gas, or powders. Background Technology

[0002] Generally, a Mechanical Vapor Recompression (MVR) system is a waste heat recovery process that utilizes external power to evaporate low-temperature, low-pressure waste steam discarded during production, compresses it into high-temperature, high-pressure steam, and reuses it as a heating source required for the production process.

[0003] This mechanical steam recompression system is equipped with conveying devices, such as blowers and pumps, that convey steam by the rotation of an electric motor.

[0004] In other words, the transfer device is fixed to the motor shaft of the electric motor and draws air or steam into the casing by means of an impeller that rotates and passes through the intake portion of the casing, and the steam compressed between the casing and the impeller is discharged to the outside of the casing through the discharge port.

[0005] However, conventionally, there was a problem in which process fluids such as steam and gas discharged from the transfer device leaked toward the MVR system, deforming the journals, thrust bearings, and drive shafts installed between them, and furthermore, the attachment or formation of foreign matter (scale) on the outer surface reduced the lifespan of precision parts.

[0006] To solve this problem, a so-called mechanical seal is installed between the drive shaft connecting the impeller and the motor and the fixed housing to prevent the process fluid from leaking out.

[0007] However, these mechanical seals for drive shafts have a problem in that their sealing performance is significantly reduced because, when rotating at high speeds, wear and damage occur due to friction with the drive shaft and heat generated, making it difficult to completely block leakage of process fluid.

[0008] In addition, mechanical seals have a limitation in that they cannot continuously maintain airtightness because the internal pressure increases when the contact surface between the rotor and the stator, i.e., the seal face, is continuously rotated while high-temperature and high-pressure process fluids and powders are introduced.

[0009] It is stated that the background technology or prior art described herein refers to information possessed by the inventor or acquired during the process of deriving and completing the present invention, and is specified merely to aid in understanding the technical significance of the present invention and to be useful for prior art search and examination, and does not mean technology that was generally known and widely used in the technical field to which the invention belongs prior to the filing of the present invention. Prior art literature

[0010] KR 10-2024-0141558 A 2024. 09. 27.KR 10-2029781 B1 2019. 10. 01.KR 10-2279237 B1 2021. 07. 13. The problem to be solved

[0011] Accordingly, the inventors of the present invention, while comprehensively considering the aforementioned matters and with the idea of ​​solving the technical limitations and problems of existing mechanical seals for drive shafts, conceived the present invention as a result of tireless research to develop a rotary shaft sealing device with a new structure capable of maintaining airtightness by preventing process fluids or powders from leaking along the drive shaft, by forming a thin hydrodynamic lubricating surface and an airtight barrier layer (airproof) by circulating a barrier fluid (compressed air, inert gas, nitrogen, etc.) in the gap between the drive shaft and the seal ring at a pressure higher than that of process fluids such as steam or gas while the sealing surface of the sealing maintains a loose contact state with the drive shaft, and also protecting against contamination by sucking in and removing process fluids or powders through negative pressure action when they enter between the drive shaft and the sealing.

[0012] Therefore, the technical problem and objective of the present invention is to provide a rotary shaft sealing device that prevents leakage of process fluid or powder by providing a physical barrier with a pressure higher than that of the process fluid between the drive shaft and the seal.

[0013] Another technical problem and objective of the present invention is to provide a rotary shaft sealing device capable of sucking in and removing process fluid or powder introduced between the drive shaft and the sealing through negative pressure action.

[0014] The technical problems and objectives that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems and objectives will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0015] A specific means according to an aspect of the present invention for effectively achieving a specific technical purpose while embodying a new concept for solving the technical problem of the present invention as described above is a rotating shaft sealing device installed between a conveying device comprising a drive shaft rotated by a drive motor, an impeller connected to the drive shaft by a coupling and rotating, and a casing housing the impeller, wherein the device comprises a sleeve fixed to the outer surface of the drive shaft via a packing, a seal housing covering the outer surface of the sleeve and having a plurality of sealing grooves arranged along the longitudinal direction of the drive shaft on its inner surface, a plurality of seal rings arranged along the longitudinal direction of the drive shaft and divided into several segments to be radially expandable between the sleeve and the seal housing and received in the sealing grooves of the seal housing, and a plurality of seal rings arranged along the longitudinal direction of the drive shaft, and an outer surface of the sealing ring to support the annular gap between the segments of the sealing ring. A rotary shaft sealing device is presented, characterized by including an annular garter spring inserted into a spring groove.

[0016] Thus, the present invention can minimize leakage of process fluid because the sealing surface of the seal maintains a loose contact state through direct contact with the drive shaft or through directional change.

[0017] In addition, a preferred aspect of the present invention comprises a chamber formed on the inner circumference of the seal housing between the seals, an inlet formed in the seal housing to communicate with the chamber for injecting a barrier fluid into the gap between the sleeve and the seal housing through the chamber, and an outlet formed in the seal housing to communicate with the chamber for discharging the barrier fluid injected through the inlet. By circulating a barrier fluid (compressed air, inert gas, nitrogen, etc.) for maintaining airtightness in the gap between the drive shaft and the seal ring at a pressure higher than that of a process fluid such as steam or gas, a thin hydrodynamic lubricating surface and an airtight barrier layer (airproof) can be formed, thereby reliably blocking the leakage of process fluid or powder along the drive shaft and maintaining airtightness performance.

[0018] In addition, a preferred aspect of the present invention is configured to further include an intake formed in the seal housing to communicate with the inner surface of the seal housing in order to suck in and remove process fluid or powder flowing into the gap between the sleeve and the seal housing by negative pressure action, so that even if process fluid or powder particles unexpectedly flow into the gap between the drive shaft and the sealing, they can be quickly sucked in and removed by negative pressure action.

[0019] In addition, a preferred aspect of the present invention is configured to further include a surge proof formed by protruding from the edge of one end of the sleeve and the outer surface of the sleeve corresponding to the location of the chamber, respectively, to buffer so as not to affect the flow of process fluid or powder exiting through the suction port even if the pressure or flow rate of the barrier fluid flowing through the gap between the sleeve and the seal housing changes rapidly, thereby allowing the process fluid or powder to exit smoothly through the suction port even if the pressure or flow rate of the barrier fluid changes rapidly.

[0020] In addition, a preferred aspect of the present invention is configured to further include a detent embedded in the sealing groove of the seal housing and resisting the force moving the seal to maintain a constant operating position and operating stroke of the seal, thereby allowing the sealing surface of the seal to maintain a loose contact state through direct contact or directional change with the sleeve, so as to minimize leakage of the process fluid. Effects of the invention

[0021] According to an embodiment that implements the technical concept on which a unique solution means is based to solve the technical problem of the present invention, a barrier fluid (compressed air, inert gas, nitrogen, etc.) for maintaining airtightness is circulated in the gap between the sleeve and the seal housing at a pressure higher than that of the process fluid, such as steam or gas, thereby forming a thin hydrodynamic lubricating surface and a physical barrier (airproof), which prevents the process fluid or powder from leaking along the drive shaft and thus maintains airtightness performance.

[0022] In addition, since the sealing surface maintains a loose contact state through direct contact or directional change with the sleeve depending on the flow of the barrier fluid, leakage of the process fluid can be minimized.

[0023] In addition, even if process fluid or powder particles enter the gap between the sleeve and the seal housing, they are sucked in and removed by negative pressure, protecting against contamination and significantly extending the service life.

[0024] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims. Brief explanation of the drawing

[0025] FIG. 1 is a drawing for easy understanding of a transfer device in which a rotating shaft sealing device according to an embodiment of the present invention is installed. FIG. 2 is a perspective view showing a rotary shaft sealing device according to an embodiment of the present invention. FIG. 3 is a perspective view showing a disassembled part of a rotary shaft sealing device according to an embodiment of the present invention. FIG. 4 is a perspective view showing the main components constituting a rotary shaft sealing device according to an embodiment of the present invention. FIG. 5 is a cross-sectional view showing a rotating shaft sealing device according to an embodiment of the present invention. FIG. 6 is a cross-sectional view to help understand the operating state of a rotary shaft sealing device according to an embodiment of the present invention. Specific details for implementing the invention

[0026] Hereinafter, embodiments according to the present invention will be described in more detail with reference to the attached drawings.

[0027] Prior to this, it is specified that the terms described below are defined in consideration of their functions in the present invention, and that they should be interpreted in accordance with the concept consistent with the technical spirit of the present invention and the meaning commonly accepted or recognized in the relevant technical field.

[0028] In addition, if it is determined that a detailed description of known functions or configurations related to the present invention could obscure the essence of the present invention, such detailed description is omitted.

[0029] It is stated that the attached drawings may be partially exaggerated or simplified for the purpose of explaining the configuration, operation, and operating principles of the technology, as well as for ease of understanding and clarity of the technology, and that each component in the drawings does not exactly correspond to the actual size and shape.

[0030] In addition, the term "and / or" in this specification means a combination of multiple related described items or includes any of the multiple related described items, and when a part is said to include a certain component, it means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0031] In other words, terms such as "include" and "have" as set forth in this specification mean that there is a feature, number, step, process, operation, component, part, or combination thereof, and should be understood as not excluding the existence or addition of one or more other features, numbers, steps, processes, operations, components, parts, or combinations thereof.

[0032] Furthermore, each process and step may occur differently from the specified order unless the context clearly indicates a specific sequence. That is, each process and step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

[0033] Meanwhile, the terms "part" and "unit" used in the present invention refer to a unit or module form that performs a role in processing at least one intended function or a certain operation in a device or system, and this can be implemented through means such as hardware, software, or a combination of hardware and software, or a device or assembly capable of performing independent operations.

[0034] In addition, the term "module" as used in the present invention may refer to a unit comprising one or more combinations of hardware and software, and may be interchangeably used with terms such as unit or component, and may be the smallest unit or part thereof of a component formed integrally, or may be the smallest unit or part thereof that performs one or more functions, and may be implemented mechanically or electronically.

[0035] Furthermore, terms such as top, bottom, upper surface, lower surface, or upper, lower, upper side, lower side, front / rear, left / right, etc. used in the present invention are used for convenience to distinguish relative positions or explain directions of movement for each component. For example, the upper part of a drawing may be named or referred to as the upper part and the lower part as the lower part, and the length direction may be named or referred to as the front / rear direction and the width direction as the left / right direction.

[0036] In addition, terms such as "first," "second," etc. used in the present invention may be used to describe various components. That is, terms such as "first," "second," etc. may be used solely for the purpose of distinguishing one component from another.

[0037] [Best mode for carrying out the invention]

[0038] A rotating shaft sealing device (100) according to an embodiment of the present invention is installed between a drive shaft (30) that is rotated by a drive motor (10) and a transfer device (20) as shown in FIG. 1.

[0039] Here, the transfer device (20) is configured to include an impeller (23) that rotates by being connected to a drive shaft (30) by an axial coupling, and a casing (25) that accommodates the impeller (23).

[0040] And the transfer device (20) includes a drive motor (10) and a bearing module (40).

[0041] The drive motor (10) is driven when power is applied to provide rotational power to the drive shaft (30).

[0042] The bearing module (40) fixes the drive shaft (30) in a fixed position and supports the load applied to the drive shaft (30), reducing frictional resistance so that it rotates smoothly by the drive motor (10).

[0043] That is, the conveying device (20) forcibly conveys process fluids such as steam, gas, or powders by generating suction force through the rotation of the impeller (23) connected to the drive shaft (30) by a shaft coupling, and the drive motor (10) rotates the drive shaft (30) by rotational driving force.

[0044] At this time, process fluids such as steam and gas, or powders, that flow into the casing (25) of the transfer device (20) are discharged through the discharge port (27).

[0045] The main elements constituting the rotating shaft sealing device (100) according to an embodiment of the present invention include a sleeve (110), a seal housing (120), a seal (130), a garter spring (140), and a detent (150), as shown in FIGS. 2 to 6.

[0046] Sleeve (110)It is formed in a cylindrical shape and is fixed to the outer surface of the drive shaft (30) via a plurality of ring-shaped packings (111).

[0047] That is, the packing (111) is mounted on the mutual contact surface to reliably seal the inner surface of the sleeve (110) and the outer surface of the drive shaft (30).

[0048] And a surgeproof (112) is formed protrudingly on the edge of one end of the sleeve (110) and on the outer surface of the sleeve (110) corresponding to the position of the chamber (122) on the inner surface of the seal housing (120).

[0049] That is, the surgeproof (112) acts as a buffer so that even if the pressure or flow rate of the barrier fluid flowing through the gap between the sleeve (110) and the seal housing (120) changes rapidly, it does not affect the flow of the process fluid or powder escaping through the suction port (125) of the seal housing (120).

[0050] And at one end edge of the sleeve (110), a flange (113) for flange coupling (flange union) is integrally formed to be joined to the impeller (23) of the transfer device (20) using bolts, etc.

[0051] Sil-housing (120) The outer surface of the sleeve (110) is formed in a cylindrical shape to cover the outer surface, and a plurality of sealing grooves (121) are formed at regular intervals in the axial direction of the drive shaft (30) on the inner surface.

[0052] That is, the inner surface of the seal housing (120) is positioned with a certain gap from the outer surface of the sleeve (110) so as not to cause contact interference when the drive shaft (30) rotates, and the sealing grooves (121) are arranged adjacent to each other along the axis of the drive shaft (30).

[0053] And a chamber (122) is formed in the center of the inner surface of the seal housing (120).

[0054] That is, the chamber (122) is formed between the seals (130) on the inner surface of the seal housing (120).

[0055] Additionally, the seal housing (120) has an injection port (123) formed therein to allow the chamber (122) to communicate with the outside.

[0056] That is, the injection port (123) is drilled in the seal housing (120) to inject barrier fluid into the gap between the sleeve (110) and the seal housing (120) through the chamber (122).

[0057] Here, the injection port (123) can be connected to a nozzle and nipple of a separate device such as a compressor (C).

[0058] Additionally, the seal housing (120) has an outlet (124) formed therein to allow the chamber (122) to communicate with the outside.

[0059] That is, the discharge port (124) is made in the seal housing (120) to discharge the barrier fluid injected through the injection port (123) through the chamber (122).

[0060] In addition, the seal housing (120) has an intake port (125) formed so that the inner surface communicates with the outside.

[0061] That is, the suction port (125) is drilled in the seal housing (120) to remove process fluid or powder flowing into the gap between the sleeve (110) and the seal housing (120) by suctioning it through negative pressure action.

[0062] Here, the suction port (125) can be connected to a nozzle and nipple of a separate device such as a suction device (S).

[0063] And at one end edge of the seal housing (120), a flange (126) for flange coupling (flange union) is integrally formed to be joined to the casing (25) of the transfer device (20) using bolts, etc.

[0064] Sealing (130) It is divided into several segments so as to be radially expanded between the sleeve (110) and the seal housing (120), and is received within the sealing groove (121) of the seal housing (120).

[0065] And the sealing (130) forms a boundary between the sleeve (110) and the leak path, completely or partially closing it.

[0066] That is, the sealing (130) is arranged at predetermined intervals in the axial direction of the drive shaft (30) so that the sliding surface of its inner circumference seals the gap between the sleeve (110) and the seal housing (120) through which the drive shaft (30) passes, in order to prevent process fluid from leaking between the sleeve (110) that rotates with the drive shaft (30) and the fixed seal housing (120) through which the drive shaft (30) passes.

[0067] And on the outer surface of the sealing (130), a spring groove (131) is formed for inserting and mounting a part of the garter spring (140).

[0068] Here, the sealing (130) is preferably formed from a carbon material for mechanical structures that is chemically stable, wear-resistant and self-lubricating, and has properties of being a good conductor of heat and resistant to thermal changes.

[0069] Garter spring (140) is formed in an annular shape and is mounted on the outer surface of the sealing (130) to support the annular spacing between the segments of the sealing (130).

[0070] That is, a portion of the garter spring (140) is inserted into the spring groove (131) formed on the outer surface of the seal (130).

[0071] Detent (150) It is embedded in the sealing groove (121) of the seal housing (120) while being joined to the outer surface of the sealing (130) by a garter spring (140).

[0072] That is, the detent (150) is fixed to one side of the outer surface of the sealing (130) and resists the force moving the sealing (130), thereby maintaining the operating position and operating stroke of the sealing (130) constant.

[0073] [Operating Principle and Function]

[0074] The main operation, operating principle, and function of the rotary shaft sealing device according to the embodiment of the present invention configured as described above are as follows.

[0075] First, as shown in FIG. 6, the inlet port (123) of the seal housing (120) is connected to the nozzle and nipple of a separate device such as a compressor (C), so that the barrier fluid supplied from the compressor (C) is injected along the inlet port (123), flows along the gap between the sleeve (110) and the seal housing (120), and then is discharged to the outside through the outlet port (124).

[0076] That is, by forcibly circulating a sealing barrier fluid, such as compressed air, inert gas, or nitrogen, at a pressure higher than that of the process fluid in the gap between the sleeve (110) and the seal housing (120) to form a thin hydrodynamic lubricating surface and a physical barrier (airproof), the process fluid or powder can be blocked from leaking along the longitudinal direction of the drive shaft (30), thereby maintaining sealing performance.

[0077] And the suction port (125) of the seal housing (120) is connected to a nozzle and nipple of a separate device such as a suction device (S), thereby allowing the process fluid or powder flowing into the gap between the sleeve (110) and the seal housing (120) to be sucked in and removed by negative pressure.

[0078] That is, even if process fluid or powder particles enter the gap between the sleeve (110) and the seal housing (120) due to prolonged use, they are forcibly sucked in and removed by the negative pressure action of the suction device (S), thereby protecting against contamination and significantly extending the service life.

[0079] Moreover, when the transfer device (20) starts, the sealing surface of the sealing (130) maintains a loose contact state with the sleeve (110) by means of the barrier fluid flowing through the gap between the sleeve (110) and the seal housing (120), so as not to hinder the rotation of the drive shaft (30), and when the transfer device (20) ends operation, the sealing surface of the sealing (130) comes into direct contact with the sleeve (110), thereby minimizing leakage of the process fluid.

[0080] Meanwhile, it is obvious to those skilled in the art that the present invention is not limited by the embodiments described above and the attached drawings, and that it can be modified and applied in various ways not exemplified within the scope of the technical concept of the present invention, as well as widely applied by substituting each component and changing to equivalent alternative embodiments.

[0081] Therefore, content related to modifying and applying the technical features of the present invention should be interpreted as being included within the technical concept and scope of the present invention. Explanation of the symbols

[0082] 10: Drive motor 20: Blower 30: Drive shaft 40: Bearing 100: Rotary shaft sealing device 110: Sleeve 111: Packing 112: Surgeproof 113: Flange 120: Seal housing 121: Sealing groove 122: Chamber 123: Inlet 124: Outlet 125: Inlet 126: Flange 130: Sealing 131: Spring Home 140: Garter spring 150: Detent

Claims

Claim 1 A rotating shaft sealing device installed between a conveying device comprising a drive shaft rotated by a drive motor, an impeller connected to the drive shaft by a coupling and rotating, and a casing housing the impeller, wherein the rotating shaft sealing device comprises: a sleeve fixed to the outer circumference of the drive shaft via a packing; a seal housing covering the outer circumference of the sleeve and having a plurality of sealing grooves formed on its inner circumference in the axial direction of the drive shaft; a plurality of seal rings divided into several segments to be radially expandable between the sleeve and the seal housing and each received in the sealing grooves of the seal housing; and an annular garter spring mounted on the outer circumference of the seal to support the annular spacing between the segments of the seal rings. A rotary shaft sealing device characterized by including: a detent embedded in the sealing groove of the seal housing and resisting a force that moves the seal to maintain a constant operating position and operating stroke of the seal. Claim 2 A rotary shaft sealing device according to claim 1, further comprising: a chamber formed in the center portion of the inner surface of the seal housing; an inlet formed in the seal housing so that the chamber communicates with the outside to inject a barrier fluid into the gap between the sleeve and the seal housing; and an outlet formed in the seal housing so that the chamber communicates with the outside to discharge the barrier fluid injected through the inlet. Claim 3 A rotating shaft sealing device installed between a conveying device comprising a drive shaft rotated by a drive motor, an impeller connected to the drive shaft by a coupling and rotating, and a casing housing the impeller, wherein the rotating shaft sealing device comprises: a sleeve fixed to the outer circumference of the drive shaft via a packing; a seal housing covering the outer circumference of the sleeve and having a plurality of sealing grooves formed on its inner circumference in the axial direction of the drive shaft; a plurality of seal rings divided into several segments to be radially expandable between the sleeve and the seal housing and each received in the sealing grooves of the seal housing; and an annular garter spring mounted on the outer circumference of the seal to support the annular spacing between the segments of the seal rings. A rotating shaft sealing device characterized by comprising: a chamber formed in the center of the inner surface of the seal housing; an inlet formed in the seal housing so that the chamber communicates with the outside to inject a barrier fluid into the gap between the sleeve and the seal housing; an outlet formed in the seal housing so that the chamber communicates with the outside to discharge the barrier fluid injected through the inlet; and an intake formed in the seal housing so that the inner surface of the seal housing communicates with the outside to suck in and remove process fluid or powder flowing into the gap between the sleeve and the seal housing by negative pressure action. Claim 4 A rotary shaft sealing device characterized by further including, in paragraph 3, a surge proof formed by protruding from the edge of one end of the sleeve and the outer surface of the sleeve corresponding to the position of the chamber, respectively, to buffer so as not to affect the flow of process fluid or powder escaping through the suction port even if the pressure or flow rate of the barrier fluid flowing through the gap between the sleeve and the seal housing changes abruptly. Claim 5 delete

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