Drawing device

Abstract

The utility model provides a drawing device, and belongs to the technical field of dismounting devices for parts on shafts. The device is used for separating a target shaft body from a target bushing, the target bushing is sleeved with the target shaft body, the drawing device comprises a pull rod, a lifting piece, a first fixing piece and a clamping ring, the pull rod comprises a first end, a second end and a rod body, and the first end is used for stretching into the target shaft body; the lifting piece is arranged on the rod body in a sleeving mode and rotationally connected with the rod body. The first fixing piece is arranged on the rod body in a sleeving mode, and the two opposite end faces of the first fixing piece can abut against the end face of the lifting piece and the end face of the target shaft body so as to limit movement of the lifting piece; the rod body is sleeved with the clamping ring, and the first end of the clamping ring can abut against the end face of the first end of the pull rod. And the pull rod can drive the clamping ring to extend into the target bushing, so that the clamping ring abuts against the end face of the target bushing, and the target bushing is driven to be separated from the target shaft body. According to the drawing device, the bush can be prevented from being damaged in the dismounting process, and the dismounted bush can be reused conveniently.

Description

Technical Field

[0001] The utility model relates to the technical field of disassembly devices for components on a shaft, and particularly relates to a pulling device. Background Art

[0002] A bushing is an isolation component between the valve stem shaft and the valve cover inside a valve, which can reduce the friction between the valve stem shaft and the valve cover. During the maintenance of valves in power plants, if it is found that the bushing is worn or damaged, it needs to be replaced. However, since the bushing on the equipment is usually in transitional fit or interference fit with the body component to prevent the bushing from coming out, the disassembly process of the bushing is relatively difficult. The related technology usually uses a long-handled tool to knock the bushing multiple times manually and push it out, which easily damages the integrity of the bushing end face and affects the reuse of the bushing.

[0003] Therefore, how to provide a pulling device that can avoid damage to the bushing during the disassembly process and facilitate the reuse of the disassembled bushing has become an urgent technical problem to be solved. Summary of the Utility Model

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a pulling device that can avoid damage to the bushing during the disassembly process and facilitate the reuse of the disassembled bushing.

[0005] To achieve the above object, on the one hand, an embodiment of the utility model provides a pulling device for separating a target shaft body and a target bushing, wherein the target shaft body is sleeved on the target bushing, and the pulling device includes:

[0006] A pull rod, including a first end, a second end opposite to the first end, and a rod body located between the first end and the second end, and the first end is used for extending into the target shaft body;

[0007] A lifting member, sleeved on the rod body and rotatably connected to the rod body;

[0008] A first fixing member, sleeved on the rod body, and two opposite end faces of the first fixing member can respectively abut against the end faces of the lifting member and the target shaft body to limit the movement of the lifting member;

[0009] A snap ring, sleeved on the rod body, and the first end of the snap ring can abut against the end face of the first end of the pull rod;

[0010] Wherein, the pull rod can drive the snap ring to extend into the target bushing, so that the snap ring abuts against the end face of the target bushing, and drive the target bushing to disengage from the target shaft body.

[0011] A drawing device proposed by the present utility model has at least the following beneficial effects: The drawing device includes a pull rod, a lifting member, a first fixing member, and a snap ring. Among them, the pull rod includes a first end, a second end opposite to the first end, and a rod body located between the first end and the second end. The first end is used to extend into the target shaft body; the lifting member is sleeved on the rod body and is rotatably connected to the rod body; the first fixing member is sleeved on the rod body, and two opposite end faces of the first fixing member can respectively abut against the end faces of the lifting member and the target shaft body to limit the movement of the lifting member; the snap ring is connected to the pull rod. When drawing the target bushing, the snap ring is sleeved on the rod body, and the first end of the snap ring can abut against the end face of the first end of the pull rod; the pull rod can drive the snap ring to extend into the target bushing so that the snap ring abuts against the end face of the target bushing and drive the target bushing to separate from the target shaft body. The device can make the lifting member move in the correct direction by abutting the first fixing member against the end face of the target shaft body. Further, the device can specifically apply a pulling force through the lifting member to make the snap ring move along the pull rod towards the outside of the target shaft body, thereby driving the target bushing to be pulled out of the target shaft body. Therefore, compared with the method of manually knocking the bushing multiple times with a long-handled tool and pushing it out in the related art, the present utility model can avoid damage to the bushing during disassembly and facilitate the reuse of the bushing after disassembly.

[0012] According to some embodiments of the present utility model, a first flange is provided on the first end of the pull rod, and a second flange is provided on the snap ring, and the first flange is used to abut against the second flange.

[0013] According to some embodiments of the present utility model, the outer diameter of the first flange is smaller than the inner diameter of the target bushing, and the inner diameter of the target bushing is smaller than the outer diameter of the second flange.

[0014] According to some embodiments of the present utility model, the snap ring includes a plurality of clamping portions, and the plurality of clamping portions are arranged at intervals and form an annular structure around the rod body.

[0015] According to some embodiments of the present utility model, the plurality of clamping portions are arranged at equal intervals.

[0016] According to some embodiments of the present utility model, an external thread is provided on the outer peripheral wall of the rod body, the lifting member is a lifting nut, and the lifting nut is provided with an internal thread threadedly connected to the external thread.

[0017] According to some embodiments of the present utility model, the first fixing member is a circular cylinder, and the circular cylinder has a first annular surface and a second annular surface arranged opposite to each other. The first annular surface is used to contact the lifting member, and the second annular surface is used to contact the end face of the target shaft body;

[0018] Among them, the outer diameter of the first annular surface is equal to the outer diameter of the second annular surface, and the inner diameter of the first annular surface is smaller than the inner diameter of the second annular surface.

[0019] According to some embodiments of the present utility model, the inner diameter of the first annular surface is smaller than the outer diameter of the lifting member;

[0020] The inner diameter of the second annular surface is smaller than the outer diameter of the target shaft body, and the inner diameter of the second annular surface is larger than the outer diameter of the target bushing.

[0021] According to some embodiments of the present utility model, a through hole for the rod body to pass through is provided on the first fixing member, and the aperture of the through hole gradually increases from the end close to the lifting member to the end far from the lifting member; or,

[0022] The aperture of the through hole gradually decreases from the end close to the lifting member to the end far from the lifting member.

[0023] According to some embodiments of the present utility model, the second end of the pull rod is a prismatic structure for cooperating with a wrench.

[0024] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present utility model. Description of the Drawings

[0025] Figure 1A is a schematic cross-sectional structure diagram of a valve provided by an embodiment of the present utility model;

[0026] Figure 1B is a schematic structure diagram of a bushing provided by an embodiment of the present utility model;

[0027] Figure 2 is a schematic structure diagram of a pulling device provided by an embodiment of the present utility model;

[0028] Figure 3 is an exploded structure diagram of a pulling device provided by an embodiment of the present utility model;

[0029] Figure 4 is a schematic structure diagram of a pull rod provided by an embodiment of the present utility model;

[0030] Figure 5 is a schematic structure diagram of a lifting member provided by an embodiment of the present utility model;

[0031] Figure 6 is a schematic structure diagram of a first fixing member provided by an embodiment of the present utility model;

[0032] Figure 7It is a schematic structural diagram of a snap ring provided by an embodiment of the present utility model;

[0033] Figure 8 It is a sectional view of a usage scenario structure of a drawing device provided by an embodiment of the present utility model.

[0034] Reference numerals: valve 100, valve cover 110, valve stem shaft 120, bushing 130, drawing device 200, pull rod 210, first end 211, second end 212, rod body 213, first flange 214, lifting member 220, first fixing member 230, first annular surface 231, second annular surface 232, through hole 233, snap ring 240, clamping portion 241, second flange 242, target shaft body 300, target bushing 310. Detailed implementation manners

[0035] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.

[0036] In the description of the present utility model, it should be understood that the orientation descriptions such as up, down, front, back, left, right, etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0037] In the description of the present utility model, the meaning of several is more than one, and the meaning of multiple is more than two. Understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0038] In the description of the present utility model, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.

[0039] In the description of the present utility model, the descriptions with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0040] Before further elaborating on the embodiments of the present utility model, the nouns and terms involved in the embodiments of the present utility model are described, and the nouns and terms involved in the embodiments of the present utility model are applicable to the following explanations:

[0041] Valve: It is a mechanical device used to control the flow of fluids. A valve can regulate, open, or close the flow of liquids, gases, or other fluids in a pipeline. Valves are widely used in various industrial fields, including but not limited to petroleum, chemical industry, power stations, water treatment, construction, ships, and food processing, etc.

[0042] Valve stem shaft: Usually simply referred to as the valve stem, it is a key component in a valve used to connect the valve operating mechanism and the internal moving parts (such as valve discs or valve plates) of the valve.

[0043] Valve bonnet: It is a part of the valve structure. The valve bonnet is located at the upper part of the valve, which serves to enclose the internal space of the valve, fix the valve stem, and protect the internal components of the valve.

[0044] Bushing: It is a mechanical component, usually designed in a sleeve shape, used to wrap or install on other components to provide support, reduce friction, absorb shock, or isolate components.

[0045] In a power station, valves are important component devices of the power station. Since the scale of a power station is usually large, each unit may have thousands of valves. Inside some valves, a bushing may be installed between the valve stem shaft and the valve bonnet, such as a guide bushing or an anti-torsion bushing. During the maintenance process of the valve, if it is found that the bushing is severely worn or the components on the bushing are damaged, a new bushing spare part needs to be replaced.

[0046] The bushing is an isolation component between the valve stem shaft and the valve cover inside the valve, which can reduce the friction between the valve stem shaft and the valve cover. During the maintenance of the valve in the power station, if the bushing is found to be worn or damaged, it needs to be replaced. However, in order to ensure the stability of the bushing during the normal operation of the valve, the bushing and the valve body components usually adopt transitional fit or interference fit. For example, the bushing is generally installed on the corresponding part of the valve body by heating or cooling, and riveting treatment is carried out at the end for the installation of the bushing. But this installation method makes it difficult to disassemble the bushing, and traditional tools such as internal bearing pullers cannot disassemble long bushings due to size limitations. Since the valve stem shaft generally has a small diameter, the clearance between the valve stem shaft and the bushing becomes very small, so it is impossible to use internal bearing disassembly tools to disassemble the bushing.

[0047] In the related art, there are mainly two ways to disassemble the bushing: one is to machine turn, drill or mill to thin the thickness of the bushing and then pry it out, but this method is a destructive removal, which may damage the inner wall of the valve cover, and the pried-out bushing cannot be reused; the other is to manually use a long-handled tool (such as an iron rod or a flat screwdriver) to knock the bushing and then push it out, but this method is difficult to take out the bushing in a tightly fitted situation, and may damage the integrity of the bushing end face, affecting the reuse of the bushing. Therefore, how to provide a pulling device that can avoid damage to the bushing during the disassembly process and facilitate the reuse of the disassembled bushing has become an urgent technical problem to be solved.

[0048] Based on this, the embodiment of the present invention provides a pulling device that can avoid damage to the bushing during the disassembly process and facilitate the reuse of the disassembled bushing.

[0049] Please refer to Figure 1A , Figure 1A which is a schematic cross-sectional structure diagram of a valve provided by the embodiment of the present invention. In some embodiments, as Figure 1A shown, the valve 100 includes a valve cover 110, a valve stem shaft 120, and a bushing 130 (other components such as screws are not shown). Among them, the bushing 130 is located between the valve cover 110 and the valve stem shaft 120, and is used to reduce the friction between the valve stem shaft 120 and the valve cover 110. And the bushing 130 and the valve cover 110 are usually in transitional fit. Since the valve stem shaft 120 and the valve body components (such as the valve cover) are not fixed, during the disassembly process of the bushing 130, the valve stem shaft 120 can be taken out first, and then the bushing 130 can be disassembled.

[0050] Please refer to Figure 1B , Figure 1B which is a schematic structure diagram of a bushing provided by the embodiment of the present invention. In some embodiments, as Figure 1BAs shown, the bushing 130 can be an annular cylinder. Specifically, the inner diameter of the bushing 130 is slightly larger than the outer diameter of the valve stem shaft 120. For example, the diameter difference between the two is 1 millimeter (mm), etc., which is not limited.

[0051] It should be noted that an annular cylinder refers to a spatial geometric body enclosed by two parallel and coaxial circles. Thus, the cross-section of the annular cylinder can be an annulus, also known as an annular surface.

[0052] Please refer to Figure 2 and Figure 3 , Figure 2 is a schematic structural diagram of a drawing device provided by an embodiment of the present invention. The drawing device 200 includes: a pull rod 210, a lifting member 220, a first fixing member 230, and a snap ring 240. Among them, the pull rod 210 includes a first end 211, a second end 212 opposite to the first end 211, and a rod body 213 located between the first end 211 and the second end 212. When pulling out the target bushing 310 disposed in the target shaft body 300, the first end 211 is used to extend into the target shaft body 300. The lifting member 220 is sleeved on the rod body 213 and is rotatably connected to the rod body 213; the first fixing member 230 is sleeved on the rod body 213, and the opposite two end faces of the first fixing member 230 can respectively abut against the end faces of the lifting member 220 and the target shaft body 300 to limit the movement of the lifting member 220; the snap ring 240 is sleeved on the rod body 213, and the first end of the snap ring 240 can abut against the end face of the first end 211 of the pull rod 210; among them, the pull rod 210 can drive the snap ring 240 to extend into the target bushing 310 so that the snap ring 240 abuts against the end face of the target bushing 310 and drives the target bushing 310 to disengage from the target shaft body 300. The working principle is as follows:

[0053] When pulling out the target bushing 310, when the lifting member 220 is rotated, a relative movement is generated between the pull rod 210 and the lifting member 220. Since the lifting member 220 abuts against the first fixing member 230, and the first fixing member 230 abuts against the target shaft body 300, and the target shaft body 300 is stationary, the first fixing member 230 restricts the downward movement of the lifting member 220, and the first fixing member 230 generates an upward reaction force on the pull rod 210, that is, the pull rod 210 can move upward in a direction away from the first fixing member 230. Since the first end 211 of the pull rod 210 abuts against the snap ring 240, when the pull rod 210 moves upward, it can drive the snap ring 240 to move in the direction of the target bushing 310 until one end of the snap ring 240 abuts against the end face of the target bushing 310, thereby driving the target bushing 310 to move, and further causing the target bushing 310 to disengage from the target shaft body 300.

[0054] It should be noted that the lifting member 220 of the drawing device 200 of the present utility model can contact the end face of the target shaft body 300 through the first fixing member 230 to ensure that the lifting member 220 moves in the correct direction. Further, the present utility model can specifically apply a pulling force to the pull rod 210 by rotating the lifting member 220, so that the snap ring 240 moves along the pull rod 210 to the outside of the target shaft body 300, thereby driving the target bushing 310 to be pulled out from the target shaft body 300. Therefore, compared with the method of manually knocking the bushing multiple times with a long-handled tool and pushing it out in the related art, the present utility model can avoid damage to the bushing during disassembly and facilitate the reuse of the bushing after disassembly.

[0055] It should be noted that the target shaft body 300 can be any device having a cylindrical inner cavity in which the target bushing 310 is accommodated. Among them, the target shaft body 300 and the target bushing 310 accommodated therein usually adopt an interference fit or an interference fit.

[0056] Please refer to Figure 3 , Figure 3 , which is an exploded view of the structure of a drawing device provided by an embodiment of the present utility model. The drawing device 200 can sequentially include a lifting member 220, a first fixing member 230, a snap ring 240, and a pull rod 210 from top to bottom. Specifically, when assembling the drawing device 200, the snap ring 240 can be first assembled on the pull rod 210, and the snap ring 240 can be assembled outside the first end 211 of the pull rod 210. Further, the first fixing member 230 can be placed outside the rod body 213 of the pull rod 210. Finally, the lifting member 220 can be placed outside the rod body 213 of the pull rod 210.

[0057] It should be noted that when the drawing device 200 is placed upright, the first fixing member 230 can be arranged above the snap ring 240, and the first fixing member 230 can be a cylindrical bracket. When disassembling the target bushing 310, the first fixing member 230 contacts the end face of the target shaft body 300, and at this time, the first fixing member 230 does not cover the snap ring 240. After the lifting member 220 applies a pulling force, the first fixing member 230 may partially cover the outer surface of the snap ring 240 during the process of removing the target bushing 310. Therefore, the inner diameter of the first fixing member 230 needs to be greater than the maximum outer diameter of the snap ring 240.

[0058] Please refer to Figure 4 , Figure 4This is a schematic structural diagram of a pull rod provided by an embodiment of the present utility model. Among them, the pull rod 210 successively includes a second end 212, a rod body 213, and a first end 211 from top to bottom. The pull rod 210 connects the first fixing member 230 and the snap ring 240, and can transmit the pulling force generated by the lifting member 220 to the snap ring 240, thereby driving the target bushing 310 to move outward from the target shaft body 300. Specifically, a first flange 214 is provided on the first end 211, and the upper surface of the first flange 214 contacts and fits with the lower surface of the second flange 242 of the snap ring 240. The first flange 214 is used to abut against the second flange 242. It can be understood that the upper surface of the first flange 214 is the side of the first flange 214 close to the rod body 213, and the lower surface of the second flange 242 is the side of the second flange 242 away from the rod body 213. The outer diameter of the first flange 214 can be smaller than the inner diameter of the target bushing 310, so that the first end 211 can directly extend into the target shaft body 300 and pass through the target bushing 310. The inner diameter of the target bushing 310 is smaller than the outer diameter of the second flange 242, so that one end of the snap ring 240 can abut against the end face of the target bushing 310.

[0059] It should be noted that external threads can be provided on the outer peripheral wall of the rod body 213, and the rod body 213 is respectively connected to the lifting member 220 and the first fixing member 230. The lifting member 220 can be a lifting nut, and the lifting nut is provided with internal threads that are threadedly connected to the external threads, so that when the lifting member 220 is rotated, relative movement occurs between the pull rod 210 and the lifting member 220.

[0060] It should be noted that the second end 212 of the pull rod 210 can be a prismatic structure for cooperating with a wrench. When the lifting member 220 is screwed downwards, if the friction force between the rod body 213 and the lifting member 220 is too large, the entire pulling device 200 may rotate. At this time, a wrench matching the prism shape can be used to clamp the second end 212 of the pull rod 210 to limit the overall rotation of the pulling device 200, so that relative movement occurs between the pull rod 210 and the lifting member 220, thereby driving the target bushing 310 to move upwards.

[0061] It should be noted that the diameter, length, and model of the external threads of the pull rod 210 can be comprehensively determined according to the size of the target bushing 310 and the space of the target shaft body 300, and no specific limitation is made here.

[0062] Please refer to Figure 5 , Figure 5It is a schematic structural diagram of a lifting member provided by an embodiment of the present utility model. Specifically, the lifting member 220 can be a lifting nut, and an internal thread matching the external thread can be provided inside the lifting nut. Therefore, the biting force generated by the screw thread engagement can be applied to disassemble the target bushing 310. Specifically, when the lifting member 220 is rotated downward to engage with the external thread provided on the rod body 213, since the lifting member 220 abuts against the first fixing member 230, the first fixing member 230 abuts against the target shaft body 300, and the first fixing member 230 abuts against the target shaft body 300, and the target shaft body 300 is immovable, the first fixing member 230 restricts the lifting member 220 from moving downward continuously. At this time, the first fixing member 230 generates an upward reaction force on the pull rod 210, that is, the pull rod 210 will move upward relative to the lifting member 220, and then the pull rod 210 drives the target bushing 310 to disengage from the target shaft body 300.

[0063] Please refer to Figure 6 , Figure 6 It is a schematic structural diagram of a first fixing member provided by an embodiment of the present utility model. The first fixing member 230 is connected to the lifting member 220. The first fixing member 230 is a circular cylindrical body, and the circular cylindrical body has a first annular surface 231 and a second annular surface 232 which are oppositely arranged. The first annular surface 231 is used to contact the lifting member 220, and the second annular surface 232 is used to contact the end surface of the target shaft body 300.

[0064] Specifically, the first annular surface 231 can be the upper surface of the first fixing member 230, and the second annular surface 232 can be the lower surface of the first fixing member 230. Among them, the outer diameter of the first annular surface 231 is equal to the outer diameter of the second annular surface 232, and the inner diameter of the first annular surface 231 is smaller than the inner diameter of the second annular surface 232. The inner diameter of the first annular surface 231 is smaller than the outer diameter of the lifting member 220 so that the lifting member 220 can abut against the end surface of the first fixing member 230. The inner diameter of the second annular surface 232 is smaller than the outer diameter of the target shaft body 300, and the inner diameter of the second annular surface 232 is larger than the outer diameter of the target bushing 310 so as not to affect the disassembly of the target bushing 310. The first fixing member 230 plays a role of a bracket in the pulling device 200, and the presence of this bracket does not affect the pulling process of the target bushing 310. If the first fixing member 230 is not used and only the lifting member 220 is used, the lifting member 220 will directly contact the target bushing 310 during the downward rotation process and cannot generate a lifting force on the pull rod 210.

[0065] It should be noted that a through hole 233 for the rod body 213 to pass through is formed in the first fixing member 230, and the aperture of the through hole 233 gradually increases from the end close to the lifting member 220 to the end far from the lifting member 220; or, the aperture of the through hole 233 gradually decreases from the end close to the lifting member 220 to the end far from the lifting member 220. When the aperture of the through hole 233 gradually increases from the end close to the lifting member 220 to the end far from the lifting member 220, the rod body 213 has more moving space in the through hole 233, which is convenient for the rod body 213 to adjust its position within a certain range and helps with the assembly of the snap ring 240. On the contrary, when the aperture of the through hole 233 gradually decreases from the end close to the lifting member 220 to the end far from the lifting member 220, this can increase the contact area between the rod body 213 and the first fixing member 230, and can increase the stability of the rod body 213 in the through hole 233, thereby providing a better fixing effect during the pulling process of the target bushing 310.

[0066] It should be noted that there is no thread inside the first fixing member 230. When pulling the target bushing 310, the first fixing member 230 is in contact with the end face of the target shaft body 300, and the first fixing member 230 can slide between the lifting member 220 and the target shaft body 300. When the lifting member 220 is screwed and moves downward, the lifting member 220 can press the first fixing member 230 against the target shaft body 300, and then by screwing the lifting member 220, a lifting force can be generated on the pull rod 210.

[0067] It should be noted that when the sizes of the target bushings 310 are different, the model of the first fixing member 230 can be adjusted so that the inner diameter of the lower surface of the first fixing member 230 is larger than the outer diameter of the target bushing 310, to prevent the first fixing member 230 from obstructing the removal of the target bushing 310 during the lifting process.

[0068] It should be noted that when pulling the target bushing 310, the first annular surface 231 is in contact with the lifting member 220. Therefore, the maximum outer diameter of the lifting member 220 needs to be larger than the inner diameter of the first annular surface 231, so as to facilitate the first fixing member 230 to support the lifting member 220 and limit the downward movement of the lifting member 220.

[0069] It should be noted that the second annular surface 232 is in contact with the end face of the target shaft body 300. Thus, the first fixing member 230 can serve as a bracket between the lifting member 220 and the target shaft body 300 to keep the distance between the lifting member 220 and the target shaft body 300 unchanged.

[0070] Specifically, when the lifting member 220 is turned to move downward, the internal thread of the lifting member 220 meshes with the external thread on the rod body 213. When the lifting member 220 contacts the first annular surface 231 of the first fixing member 230, the lifting member 220 cannot continue to move downward. At this time, the biting force generated by the screw engagement will cause the pull rod 210 to move upward, so as to move the snap ring 240 along the pull rod 210 to the outside of the target shaft body 300, thereby driving the target bushing 310 to be pulled out from the target shaft body 300.

[0071] Further, during the process of pulling out the target bushing 310 from the target shaft body 300, since the pull rod 210 moves upward, the first fixing member 230 may cover the target bushing 310. Therefore, the inner diameter of the second annular surface 232 needs to be greater than the outer diameter of the target bushing 310 to facilitate the removal of the target bushing 310.

[0072] Please refer to Figure 7 , Figure 7 FIG. is a schematic structural diagram of a snap ring provided by an embodiment of the present invention. Among them, the snap ring 240 connects the target bushing 310 and the pull rod 210, and can transfer the pulling force on the pull rod 210 to the target bushing 310, so as to pull out the target bushing 310. Specifically, the snap ring 240 may include at least two clamping portions 241. The plurality of clamping portions 241 are arranged at intervals and form an annular structure around the rod body 213 for easy assembly.

[0073] Further, the plurality of clamping portions 241 are arranged at equal intervals to keep the pulling force transmitted from the pull rod 210 to the target bushing 310 uniform. One end of each clamping portion 241 may include a second flange 242. When the target bushing 310 is pulled out, the upper surface of the second flange 242 may contact the bottom end face of the target bushing 310, and the lower surface of the second flange 242 may be superposed and connected to the upper surface of the first flange 214. Thus, the inner diameter of the ring corresponding to the second flange 242 may be equal to the inner diameter of the first flange 214, or the inner diameter of the ring corresponding to the second flange 242 may be slightly larger than the inner diameter of the first flange 214. Since the upper surface of the second flange 242 can abut against the end face of the target bushing 310 when the target bushing 310 is pulled out, the inner diameter of the ring corresponding to the second flange 242 may be smaller than the inner diameter of the target bushing 310, and the inner diameter of the target bushing 310 may be smaller than the outer diameter of the ring corresponding to the second flange 242.

[0074] It should be noted that when the sizes of the target bushings 310 are different, the outer diameter of the ring corresponding to the second flange 242 can be adjusted to increase the contact area between the target bushing 310 and the snap ring 240, thereby reducing the pressure per unit area and ensuring that the target bushing 310 is not damaged during the pulling process due to too small contact area.

[0075] In some embodiments, when the snap ring 240 is connected to the target bushing 310, the spacing between adjacent snap joints 241 can be equal to maintain a uniform distribution. In other embodiments, when the snap ring 240 is connected to the target bushing 310, the spacing of the snap ring 240 can be unequal, but the snap ring 240 remains centrosymmetric.

[0076] Please refer to Figure 8 , Figure 8 which is a sectional view of a usage scenario structure of a pulling device provided by an embodiment of the present utility model. Among them, a target bushing 310 is disposed inside a target shaft body 300. It should be noted that the device model of the target shaft body 300 and the type of the target bushing 310 are not specifically limited. For example, the target shaft body 300 can be a valve cover, and the target bushing 310 can be an anti-torsion bushing on the valve cover.

[0077] Specifically, when pulling the target bushing 310, the first end 211 of the pull rod 210 can be first inserted into the target shaft body 300 and passed through the target bushing 310.

[0078] Furthermore, the pull rod 210 can be placed close to any side of the target bushing 310 to facilitate reserving enough installation space for the snap ring 240. Subsequently, the snap joints 241 are installed one by one between the target bushing 310 and the pull rod 210, so that the second flanges 242 on each snap joint 241 are uniformly in contact with the target bushing 310. Then, the second annular surface 232 of the first fixing member 230 can be brought into contact with the end surface of the target shaft body 300. Finally, the lifting member 220 can be screwed onto the pull rod 210 so that the lower surface of the lifting member 220 is in contact with the first annular surface 231 of the first fixing member 230.

[0079] It should be noted that the number of installed snap joints 241 is jointly determined by the inner diameter of the target bushing 310 and the inner diameter of the first flange 214. After the snap ring 240 is installed, the pull rod 210 needs to be adjusted to the middle position of the target bushing 310 to facilitate the pulling of the target bushing 310.

[0080] Specifically, when pulling the target bushing 310, the lifting member 220 can be turned to move the lifting member 220 downward. Since the lower surface of the lifting member 220 is in contact with the first annular surface 231 of the first fixing member 230, the lifting member 220 cannot continue to move downward. At this time, when the lifting member 220 is continuously turned, the internal thread of the lifting member 220 is screwed with the external thread on the surface of the pull rod 210, generating a vertically upward force, thereby causing the pull rod 210 to move upward. After the pull rod 210 moves upward, it can drive the snap ring 240 to move outward from the target shaft body 300 along the direction of movement of the pull rod 210, thereby driving the target bushing 310 to be pulled out of the target shaft body 300.

[0081] It should be noted that when the dimensions of the target bushing 310 are different, the lengths of the first fixing member 230 and the pull rod 210 can be adjusted appropriately, and no specific limitation is made here. For example, when the target bushing 310 is a bushing with a longer dimension, the lengths of the first fixing member 230 and the pull rod 210 can be increased to facilitate the pulling out of the target bushing 310.

[0082] It can be understood that the pulling device 200 converts the force of screw rotation into a force in the vertical direction, and can generate a greater pulling force on the target bushing 310 with a smaller torque applied to the lifting member 220. Further, the pulling device 200 adopts a method of fixing the second flange 242 on each clamping portion 241 to the target bushing 310, which can increase the contact area with the target bushing 310 and is not easily damaged when a greater pulling force is applied, thereby protecting the integrity of the target bushing 310, and the removed bushing can be reused. The utility model can adjust the dimensions of the first fixing member 230 and the clamping portion 241 to adapt to the removal scenarios of bushings with different dimensions, and has a wide applicability.

[0083] The utility model significantly improves the work efficiency and the personnel protection level by designing a pulling device 200, and at the same time reduces the damage risk of equipment and bushing parts. The pulling device 200 is applicable to the removal of bushings at the guiding parts of the transmission shaft or valve stem shaft 120 in a power plant, and is also applicable to the anti-torsion bushings on the valve cover of the valve 100. Through tests, the pulling device 200 can quickly pull out the bushing in only 5 to 6 minutes on average. If the target bushing 310 is located in the control area, a shorter time for pulling out the bushing can greatly reduce the time for maintenance personnel to contact radioactive equipment. Moreover, after the bushing is pulled out, no obvious damage is found on the equipment, nor on the bushing. In addition, the device can also generate sufficient pulling force to quickly pull out the expanded and fastened bushing, reducing the probability of equipment damage. After using the device, the bushing can be reused after simple treatment without replacing with new bushing spare parts, effectively improving the production efficiency of the power plant.

[0084] The embodiments of the utility model have been described in detail above with reference to the drawings, but the utility model is not limited to the above embodiments. Various changes can be made without departing from the spirit of the utility model within the knowledge scope of those of ordinary skill in the art. In addition, the embodiments of the utility model and the features in the embodiments can be combined with each other without conflict.

Claims

1. A pulling device for separating a target shaft and a target bushing, wherein the target shaft is sleeved on the target bushing, characterized in that: The pulling device comprises: A pull rod, comprising a first end, a second end opposite to the first end, and a rod body located between the first end and the second end, wherein the first end is used to extend into the target shaft body; A lifting member, sleeved on the rod body and rotatably connected to the rod body; A first fixing member is sleeved on the rod body, and two opposite end surfaces of the first fixing member can respectively abut against the end surfaces of the lifting member and the target shaft body to limit the movement of the lifting member; A clamping ring, sleeved on the rod body, wherein the first end of the clamping ring can abut against the end surface of the first end of the pull rod; The pull rod can drive the clamping ring to extend into the target bushing, so that the clamping ring abuts against the end surface of the target bushing and drives the target bushing to separate from the target shaft body.

2. The pulling device according to claim 1, characterized in that: A first flange is arranged on the first end of the pull rod, and a second flange is arranged on the clamping ring. The first flange is used to abut against the second flange.

3. The pulling device according to claim 2, characterized in that: The outer diameter of the first flange is smaller than the inner diameter of the target bushing, and the inner diameter of the target bushing is smaller than the outer diameter of the second flange.

4. The pulling device according to any one of claims 1 to 3, characterized in that: The clamping ring comprises a plurality of clamping parts, which are arranged at intervals and form a ring structure around the rod body.

5. The pulling device according to claim 4, characterized in that: The plurality of clamping portions are arranged at equal intervals.

6. The pulling device according to any one of claims 1 to 3, characterized in that: An external thread is arranged on the outer peripheral wall of the rod body, the lifting member is a lifting nut, and the lifting nut is provided with an internal thread threadably connected to the external thread.

7. The pulling device according to any one of claims 1 to 3, characterized in that: The first fixing member is a circular cylinder having a first circular surface and a second circular surface arranged opposite to each other, the first circular surface being used for contacting the lifting member, and the second circular surface being used for contacting the end surface of the target shaft body; The outer diameter of the first annular surface is equal to the outer diameter of the second annular surface, and the inner diameter of the first annular surface is smaller than the inner diameter of the second annular surface.

8. The pulling device according to claim 7, characterized in that: The inner diameter of the first annular surface is smaller than the outer diameter of the lifting member; The inner diameter of the second annular surface is smaller than the outer diameter of the target shaft body, and the inner diameter of the second annular surface is larger than the outer diameter of the target bushing.

9. The pulling device according to any one of claims 1 to 3, characterized in that: The first fixing member is provided with a through hole for the rod to pass through, and the diameter of the through hole gradually increases from the end close to the lifting member to the end far away from the lifting member; or, The aperture of the through hole gradually decreases from an end close to the lifting member to an end far away from the lifting member.

10. The pulling device according to any one of claims 1 to 3, characterized in that: The second end of the pull rod is a prismatic structure, which is used to cooperate with a wrench.

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