Assembly process of built-in axle box wheel set

Abstract

The invention discloses an assembling technology of a built-in axle box wheel set. The assembling technology comprises the steps that S1, an axle, a bearing and a rear gear are provided; s2, the axle and the rear gear are assembled; s3, the axle and the bearing are assembled; s4, the axle and the wheels are assembled; wherein in the step S3, a lengthened pressing cylinder needs to be arranged between a bearing pressing machine and a bearing; in the step S4, a lengthened shaft needs to be arranged at the axle end of the axle and used for pre-sleeving the wheel. According to the assembling process of the built-in axle box wheel set, the bearings are pressed firstly, the lengthened pressing cylinder is additionally arranged to solve the problem that the stroke of a bearing pressing machine is insufficient, after bearing pressing is completed, the wheel set pressing process is conducted for wheel pressing, the lengthened shaft is additionally arranged at the axle end of the axle to be used for pre-sleeving the wheel, and the wheel pressing effect is ensured; in the assembling process, a quantitative standard is given to each working procedure, a reasonable tool is designed, and finally the assembling quality and efficiency of the built-in axle box wheel set can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of wheelset assembly, and in particular relates to an assembly process of a built-in axle box wheelset. Background Art

[0002] Conventional wheelsets have axle boxes on the outside and wheels on the inside. The wheels are pressed in first and then the bearings. The equipment and processes currently used are basically designed for conventional wheelsets. Unlike conventional wheelsets, the process of built-in axle box wheelsets is reversed. The bearings are pressed in first and then the wheels. This results in a too long press stroke for the bearings. Existing equipment cannot meet this production requirement, and the wheels cannot be pre-assembled at the axle end. Therefore, for the assembly of wheelsets with built-in bearings, existing equipment and processes cannot meet production requirements.

[0003] The Chinese patent application number 202111152419.5 discloses an assembly method and assembly device for an axle box bearing of an axle box built-in bogie, comprising the following steps: press-fitting a sealing ring and an axle box rear cover to the rear end of the axle box body; press-fitting the bearing into the axle box body from front to back, and installing the axle box front cover to press the bearing, thereby forming an axle box bearing assembly; and press-fitting the axle box bearing assembly onto the axle. In an embodiment of the present invention, the axle box body and the bearing are assembled into an integral assembly, and then press-fitted onto the axle, thereby smoothly realizing the assembly of the bearing, axle box body and axle of the axle box built-in bogie.

[0004] The Chinese patent application number 201911033291.3 discloses a variable gauge wheelset axle box bearing assembly device and assembly method, comprising: a process shaft, which includes a process shaft body and shaft shoulders arranged at both ends of the process shaft body; inner sleeves, respectively sleeved on the process shaft body and respectively adapted to the shaft shoulders on the corresponding sides; bearing guide sleeves, respectively connected to the two ends of the process shaft body; bearing outer sleeve components, respectively sleeved on the bearing guide sleeves on the corresponding sides; and a press-fitting sleeve component, respectively arranged at both ends of the process shaft body, the end of the press-fitting sleeve component facing the bearing guide sleeve is laid on the bearing guide sleeve, wherein, by driving the press-fitting sleeve component to move in the direction of the shaft shoulder, the bearing outer sleeve component is pushed from the bearing guide sleeve to the inner sleeve and abuts against the shaft shoulder. The variable gauge wheelset axle box bearing assembly device has the advantage of being able to meet the requirements of press-fitting of the axle box bearing of the variable gauge wheelset.

[0005] The Chinese patent application number 202311564895.7 discloses an assembly process for a wheelset cylindrical roller bearing axle box assembly, which includes the following steps: S1. Clean the journal and dust seat, and then apply grease on the surface; S2. Heat the labyrinth ring, insert the dust seat after heating, and use the impact sleeve to hit the labyrinth ring to complete the installation; S3. After the labyrinth ring is installed, hot-install the inner ring of the bearing, heat the inner ring of the bearing, insert the journal after heating, and use the pressure cover to press for a period of time; S4. Remove the pressure cover and push it onto the inner ring of the bearing after the outer ring and the box are assembled; S5. Install the oil injection pressure cover on the shaft end, the outer cylindrical surface of the oil injection pressure cover is designed with evenly distributed notches, rotate the outer ring of the bearing to align the gap between the bearing rollers with the notches on the oil injection pressure cover, insert the oil injection nozzle, and perform the grease injection operation; S6. After the grease injection is completed, remove the oil injection pressure cover, install the end cover on the shaft end, and finally install the front cover, which is convenient for assembly line operation and greatly improves assembly efficiency and quality.

[0006] It is desirable to provide an improved assembly process for an inboard axle box wheelset, particularly with regard to improving the quality and efficiency of assembling the inboard axle box wheelset. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an assembly process of an internal axle box wheelset, the purpose of which is to improve the assembly quality and efficiency of the internal axle box wheelset.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: an assembly process of a built-in axle box wheelset, comprising the steps of:

[0009] S1, provide axles, bearings and rear gears;

[0010] S2, assemble the axle and rear gear;

[0011] S3, assemble the axle and bearing;

[0012] S4, assembling the axle and the wheel;

[0013] Wherein, in the step S3, an extended pressing cylinder needs to be arranged between the bearing press and the bearing;

[0014] In step S4, an extension shaft needs to be provided at the end of the axle for pre-installing the wheel.

[0015] In the step S1, the axle needs to be cleaned, and after cleaning, a lubricating medium is applied to the surface of the axle.

[0016] In the step S1, before cleaning the axle, the housing, bearings and rear stop are subjected to isothermal treatment, and the isothermal treatment time is ≥ 8 hours.

[0017] In the step S2, the rear gear is first heated, and after the heating is completed, the axle and the rear gear are assembled.

[0018] In the step S2, during the assembly of the axle and the rear gear, after the rear gear is mounted on the dustproof seat on the axle, the impact sleeve is used to impact the rear gear multiple times along the axial direction.

[0019] In the step S2, the rear gear is heated in an oven at a temperature of 150°C±3°C.

[0020] In step S3, first insert the nylon sleeve into the inner hole of the bearing, then put the nylon sleeve and the bearing together onto the wheel seat of the axle, then push the bearing toward the journal of the axle, then put the extended pressing cylinder onto the plunger of the bearing press, then start the bearing press, control the plunger to extend until it presses against the shaft end of the axle, then the pressure head of the bearing press pushes the extended pressing cylinder to move axially, and the extended pressing cylinder applies pressure to the bearing until the bearing is pressed onto the journal.

[0021] In the step S3, after the bearing is press-fitted onto the journal, a feeler gauge is used to check the clearance between the rear stop and the bearing.

[0022] In step S4, the extension shaft is installed at the end of the axle, a positioning boss is provided on the extension shaft to cooperate with the center hole of the axle for positioning, and then the wheel is sleeved on the extension shaft and then sent to a wheel press machine for press fitting.

[0023] The extended shaft is a hollow structure, and a vent hole and a secondary center hole are arranged on the extended shaft, and the vent hole and the secondary center hole are communicated.

[0024] The assembly process of the built-in axle box wheelset of the present invention is to press-fit the bearings first, and then add an extended pressing cylinder to compensate for the problem of insufficient stroke of the bearing press machine. After the bearings are pressed, the process turns to the wheelset pressing process to press the wheels. An extended shaft is added to the end of the axle to pre-fit the wheel to ensure the pressing effect of the wheel. During the assembly process, quantitative standards are given to each process and reasonable tooling is designed, which can ultimately improve the assembly quality and efficiency of the built-in axle box wheelset. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] This specification includes the following drawings, which show the following contents:

[0026] Figure 1 It is a flow chart of the assembly process of the built-in axle box wheelset of the present invention;

[0027] Figure 2 It is a schematic diagram of the structure of a built-in axle box wheelset;

[0028] Figure 3 yes Figure 2 The enlarged image at point I in the middle;

[0029] Figure 4 It is a schematic diagram of the partial structure of the axle;

[0030] Figure 5 This is a schematic diagram of the rear gear installation;

[0031] Figure 6 It is a schematic diagram of the bearing being pressed onto the wheel seat;

[0032] Figure 7 It is a schematic diagram of the bearing being pressed onto the journal;

[0033] Figure 8 This is a schematic diagram of wheelset press assembly;

[0034] Fig. 9 It is a schematic diagram of the extended shaft structure;

[0035] The markings in the figure are: 1. axle; 2. rear gear; 3. bearing; 4. box; 5. wheel; 6. dust seat; 7. journal; 8. wheel seat; 9. center hole; 10. impact sleeve; 11. nylon sleeve; 12. pressure head; 13. plunger; 14. extended pressure cylinder; 15. extended shaft; 16. positioning boss; 17. secondary center hole; 18. air vent. DETAILED DESCRIPTION

[0036] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0037] In the present invention, it is necessary to understand that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "planar direction", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and 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 a limitation on the present invention.

[0038] In the following embodiments, the “first” and “second” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequential order of execution, but are merely for the convenience of description.

[0039] like Figures 1 to 9 As shown, the present invention provides an assembly process of a built-in axle box wheelset, comprising the following steps:

[0040] S1, provide axle 1, bearing 3 and rear gear 2;

[0041] S2, assembling the axle 1 and the rear gear 2;

[0042] S3, assembling the axle 1 and the bearing 3;

[0043] S4, assembling the axle 1 and the wheel 5.

[0044] Specifically, the present invention provides a standardized built-in axle box wheelset assembly process and its matching equipment and tooling, provides quantitative standards for each process and designs reasonable tooling to greatly improve the quality and efficiency of assembly.

[0045] In the above step S1, the axle 1 needs to be cleaned. After the cleaning is completed, a lubricating medium is applied to the surface of the axle 1, and the lubricating medium is grease. Figures 2 to 4 As shown, a dust seat 6, a journal 7 and a wheel seat 8 are arranged on the axle 1, the journal 7 is located between the dust seat 6 and the wheel seat 8, and the outer diameter of the dust seat 6 is larger than the outer diameters of the journal 7 and the wheel seat 8. The axle 1 is cleaned, and the journal 7 and the dust seat 6 need to be cleaned until the cleanliness reaches the level of being wiped with dust-free paper without stains.

[0046] In the above step S1, before cleaning the axle 1, the box 4, the bearing 3 and the rear stop 2 need to be subjected to isothermal treatment. The isothermal treatment time is ≥ 8 hours, which can ensure the accuracy of the assembly dimensions and reduce the impact of thermal expansion and contraction on the assembly.

[0047] In the above step S2, the rear guard 2 is first heated, and after the heating is completed, the axle 1 and the rear guard 2 are assembled. Figure 5 As shown, during the assembly process of the axle 1 and the rear stop 2, after the rear stop 2 is put on the dust seat 6 on the axle 1, the impact sleeve 10 is put on the shaft neck 7. The rear stop 2 and the impact sleeve 10 are both circular ring structures. The impact sleeve 10 is coaxial with the axle 1 and the rear stop 2. The impact sleeve 10 is used to impact the rear stop 2 along the axial direction of the axle 1 for multiple times. Listen carefully to the sound during the impact. If a clear sound is heard, it means that the rear stop 2 and the dust seat 6 fit well.

[0048] Preferably, during the assembly of the axle 1 and the rear stop 2 , the impact sleeve 10 is used to impact the rear stop 2 three times along the axial direction of the axle 1 .

[0049] In the above step S2, the rear stop 2 is heated in an oven at a temperature of 150°C±3°C. This temperature setting can satisfy the purpose of heating to expand the size to achieve direct interference fit without causing the rear stop to change in performance due to high temperature.

[0050] In the above step S3, it is necessary to set an extended pressing cylinder 14 between the bearing 3 press machine and the bearing 3, such as Figure 7As shown, the extended pressing cylinder 14 is a circular ring structure, and the extended pressing cylinder 14 is sleeved on the plunger 13 of the bearing 3 press machine, and the plunger 13 passes through the pressure head 12 of the bearing 3 press machine.

[0051] like Figure 6 and Figure 7 As shown, in the above step S3, after the rear gear 2 is installed, the bearing 3 is cold pressed. First, the nylon sleeve 11 is inserted into the inner hole of the bearing 3, and the nylon sleeve 11 is against the spacer of the bearing 3. Then, the nylon sleeve 11 and the bearing 3 are put on the wheel seat 8 of the axle 1. Then, the bearing 3 is manually pushed toward the journal 7 of the axle 1 until it is close to the front end of the journal 7. Then, the extended pressing cylinder 14 is put on the plunger 13 of the bearing 3 pressing machine. Then, the bearing 3 pressing machine is started, and the plunger 13 is controlled to extend until the plunger 13 is tight against the shaft end of the axle 1. Then, the pressure head 12 of the bearing 3 pressing machine moves to push the extended pressing cylinder 14 to move axially. The extended pressing cylinder 14 applies axial pressure to the bearing 3 until the bearing 3 is pressed onto the journal 7.

[0052] In the above step S3, after the bearing 3 is pressed onto the journal 7, a feeler gauge is used to check the clearance between the rear stop 2 and the bearing 3. The thickness of the feeler gauge is 0.01 mm. The feeler gauge is used to check the clearance between the rear stop 2 and the bearing 3. After one circle is checked, it is ensured that the feeler gauge cannot be inserted into the gap between the rear stop 2 and the bearing 3. The press-fitting of the bearing 3 is completed.

[0053] like Figure 6 As shown, the length L1 of the bearing 3, the outer diameter φd1 of the journal 7 and the outer diameter φd2 of the wheel seat 8 should be fully considered when designing the nylon sleeve 11. In order to prevent the spacer on the bearing 3 from falling off and damaging the bearing 3 during press-fitting, the nylon sleeve 11 is located between the spacer and the axle 1. During the press-fitting process, the spacer of the bearing 3 does not contact the axle 1. The length L2 of the nylon sleeve 11 is ≥ 0.85L1, d3 = d2-0.6mm, and d3 = d1-0.4mm. At the same time, after the bearing 3 is press-fitted, in order to facilitate the removal of the nylon sleeve 11, the nylon sleeve 11 is a circular ring structure, and an exit hole is set on the outer circumferential surface of the nylon sleeve 11. Two exit holes are set, and the two exit holes are symmetrically set, and the diameter of the exit hole is 30mm. After the bearing 3 is press-fitted, if the nylon sleeve 11 cannot be removed directly, a tool can be inserted into the exit hole of the nylon sleeve 11, and a pulling force is applied to the nylon sleeve 11 to pull out the nylon sleeve 11, thereby facilitating the removal of the nylon sleeve 11.

[0054] The housing 4 and the bearing 3 are clearance-fitted. After the bearing 3 is installed, the housing 4 is directly mounted on the bearing 3 manually.

[0055] like Figure 7 As shown, the length of the extended pressing cylinder 14 is L3 = L1 + 15 mm. It is calculated that this length is convenient for operation and can also meet the pressing stroke.

[0056] like Figure 8 and Fig. 9 As shown, in the above step S4, an extension shaft 15 needs to be provided at the end of the axle 1 for pre-installing the wheel 5, so as to facilitate the assembly of the wheel 5 and the axle 1.

[0057] like Figure 8 and Fig. 9 As shown, in the above step S4, the bearing 3 is press-fitted, and the axle 1 is sent to the wheel 5 press-fitting machine. Since the wheel 5 is press-fitted on the wheel seat 8 at the end, it cannot be press-fitted directly on the wheel 5 press-fitting machine. An extension shaft 15 must be installed at the end of the axle 1. A positioning boss 16 is provided on the extension shaft 15 to cooperate with the center hole 9 of the axle 1 for positioning. The extension shaft 15 and the axle 1 are in a coaxial state. Then the wheel 5 is sleeved on the extension shaft 15, and then sent to the wheel 5 press-fitting machine for press-fitting, and the wheel 5 is press-fitted on the wheel seat 8. The press-fitting must be designed with a reasonable interference and press-fitting force to ensure that the wheel 5 can be close to the bearing 3 but cannot push the bearing 3. After the press-fitting is completed, the bearing 3 is clamped between the rear gear 2 and the wheel 5, and the rear gear 2 plays an axial limit role on the bearing 3.

[0058] When designing the extended shaft 15, the concentricity requirement with the axle 1 should be considered. A positioning boss 16 is provided at the end of the extended shaft 15 to cooperate with the center hole 9 of the axle 1 for positioning to ensure the assembly quality of the wheel 5. Therefore, the design of the center hole 9 of the axle 1 needs to be considered at the beginning of the design of the axle 1. A flat-bottomed hole with a depth of 4mm is designed for positioning. Therefore, there are certain requirements for the inner diameter processing size of the flat-bottomed hole. At the same time, in order to reduce the processing accuracy, the inner diameter tolerance of the flat-bottomed hole can be set to ±0.02mm after experiments. Similarly, the tolerance of the positioning boss 16 of the extended shaft 15 can be set to (-0.2, -0.3)mm.

[0059] Through finite element calculation, the extended shaft 15 is designed as a hollow structure to meet the strength requirements while reducing weight. Figure 8 and Fig. 9 As shown, the extended shaft 15 is a hollow structure, and the first and second weight-reducing holes are arranged inside the extended shaft 15. The first weight-reducing hole extends from the end face of the positioning boss 16 along the axial direction of the extended shaft 15 to the inside of the extended shaft 15, and the second weight-reducing hole is arranged to penetrate radially along the extended shaft 15. The first and second weight-reducing holes are arranged vertically and are connected. The diameter of the first and second weight-reducing holes is 30 mm. An air hole 18 and a secondary center hole 17 are arranged inside the extended shaft 15. The air hole 18 is connected with the secondary center hole 17 and the first weight-reducing hole. The air hole 18 is located at the secondary center hole 17 and the first weight-reducing hole and the three are coaxial. The secondary center hole 17 extends to the end face of the extended shaft 15 away from the positioning boss 16, and the diameter of the air hole 18 is smaller than the diameter of the first weight-reducing hole.

[0060] The secondary center hole 17 is used to position the top of the wheel 5 press machine when the wheel 5 is press-fitted. A vent hole 18 is designed downwardly of the secondary center hole 17 to exhaust the air inside the extension shaft 15 when positioning, so as to facilitate the removal of the extension shaft 15 after press-fitting.

[0061] To ensure that the wheel 5 can fit tightly against the bearing 3 without damaging it during press-fitting, the interference should be designed to be 0.092%*d2mm when designing the press-fitting process. When the wheel 5 fits tightly against the bearing 3 at the end of press-fitting, there will be a sudden rise in pressure, and the pressure rise should be controlled not to exceed 90% of the fitting force of the bearing 3.

[0062] The assembly process of the built-in axle box wheelset of the present invention is to press-fit the bearing 3 first, add a sleeve to compensate for the problem of insufficient stroke of the bearing 3 press-fitting machine, and design a nylon sleeve 11 to fix the bearing 3 spacer to prevent the spacer from falling off during the press-fitting process and causing the bearing 3 to be scrapped. After the bearing 3 is pressed, it is transferred to the wheelset pressing process to press the wheel 5. However, because the wheel 5 is pressed at the end of the shaft, an extension shaft 15 is added to the end of the shaft to pre-cover the wheel 5. The extension shaft 15 must be packaged concentrically with the wheel seat 8. Therefore, the center hole of the shaft end and the end of the extension shaft 15 need to be designed to meet the concentricity requirement. During the wheelset press-fitting process, the shell surface of the wheel 5 is required to fit tightly with the outer end surface of the bearing 3 after pressing, but the pressure cannot be too large to cause the bearing 3 to be scrapped. Therefore, it is also necessary to design a reasonable wheel 5 press-fitting interference and press-fitting force to meet the process requirements.

[0063] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. The assembly process of the built-in axle box wheelset is characterized by: Includes steps: S1, provide axles, bearings and rear gears; S2, assemble the axle and rear gear; S3, assemble the axle and bearing; S4, assembling the axle and the wheel; Wherein, in the step S3, an extended pressing cylinder needs to be arranged between the bearing press and the bearing; In step S4, an extension shaft needs to be provided at the end of the axle for pre-mounting the wheel.

2. The assembly process of the built-in axle box wheelset according to claim 1 is characterized in that: In the step S1, the axle needs to be cleaned, and after cleaning, a lubricating medium is applied to the surface of the axle.

3. The assembly process of the built-in axle box wheelset according to claim 2 is characterized in that: In the step S1, before cleaning the axle, the housing, bearings and rear stop are subjected to isothermal treatment, and the isothermal treatment time is ≥ 8 hours.

4. The assembly process of the built-in axle box wheelset according to any one of claims 1 to 3, characterized in that: In the step S2, the rear gear is first heated, and after the heating is completed, the axle and the rear gear are assembled.

5. The assembly process of the built-in axle box wheelset according to claim 4 is characterized in that: In the step S2, during the assembly of the axle and the rear gear, after the rear gear is mounted on the dustproof seat on the axle, the impact sleeve is used to impact the rear gear multiple times along the axial direction.

6. The assembly process of the built-in axle box wheelset according to claim 4 is characterized in that: In the step S2, the rear gear is heated in an oven at a temperature of 150°C±3°C.

7. The assembly process of the built-in axle box wheelset according to any one of claims 1 to 6, characterized in that: In step S3, first insert the nylon sleeve into the inner hole of the bearing, then put the nylon sleeve and the bearing together onto the wheel seat of the axle, then push the bearing toward the journal of the axle, then put the extended pressing cylinder onto the plunger of the bearing press, then start the bearing press, control the plunger to extend until it presses against the shaft end of the axle, then the pressure head of the bearing press pushes the extended pressing cylinder to move axially, and the extended pressing cylinder applies pressure to the bearing until the bearing is pressed onto the journal.

8. The assembly process of the built-in axle box wheelset according to claim 7 is characterized in that: In the step S3, after the bearing is press-fitted onto the journal, a feeler gauge is used to check the clearance between the rear stop and the bearing.

9. The assembly process of the built-in axle box wheelset according to any one of claims 1 to 8, characterized in that: In step S4, the extension shaft is installed at the end of the axle, a positioning boss is provided on the extension shaft to cooperate with the center hole of the axle for positioning, and then the wheel is sleeved on the extension shaft and then sent to a wheel press machine for press fitting.

10. The assembly process of the built-in axle box wheelset according to claim 9, characterized in that: The extended shaft is a hollow structure, and a vent hole and a secondary center hole are arranged on the extended shaft, and the vent hole and the secondary center hole are communicated.

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