Method for manufacturing railway vehicle wheel-mounted brake discs

Abstract

The purpose of the present invention is to provide a method for manufacturing railway vehicle wheel-mounted brake discs, in which a part coming into contact with a brake pad is made of forged steel, and a heat dissipation fin on a part coming into contact with a wheel is formed by a metal 3D-printing method, to thereby implement high heat disspation characteristics as well as high rigidity.

Description

Method for manufacturing wheel-mounted brake discs for railway vehicles

[0001] The present invention relates to a method for manufacturing a wheel-mounted brake disc for a railway vehicle, and more particularly, to a method for manufacturing a wheel-mounted brake disc for a railway vehicle applied to a high-speed train.

[0002] Ordinary railway vehicles, especially high-speed trains, use externally supplied power to drive a drive motor to move along the tracks, and are equipped with wheels that come into contact with the tracks. They are also equipped with a braking device for braking the vehicle, and are structured to control the vehicle's speed.

[0003] In particular, railway vehicles are composed of high weights and move along rails, so it goes without saying that the reliability of the braking system must be ensured. Railway vehicles are equipped with axles on a bogie, and wheels that drive along the rails are mounted on both sides of the axle. The axles are equipped with a braking system. Typically, brake discs are mounted on both sides of the axle, and the brake discs generate braking force through the compressive force of the brake pads.

[0004] The above brake discs are subject to very high pressure and friction simultaneously due to repeated contact with the pads, so they must satisfy strict mechanical characteristics before they can be used in railway vehicles.

[0005] Various brake discs have been proposed considering the characteristics of railway vehicles as described above. For example, Patent Publication No. 2014-0066590 discloses a configuration of a high-heat-resistant brake disc for railway vehicles, wherein the central portion is fitted to the axle of the railway vehicle, the outer periphery is coupled to the wheel and rotates coaxially with the wheel, and at least one patterned portion made of a high-heat-resistant nanomaterial is formed on one surface of the brake disc for railway vehicles.

[0006] In addition, Patent Publication No. 2012-0132036 discloses a brake disc configuration comprising a pair of brake discs fixed to both sides of a wheel of a railway vehicle by bolts and nuts, each of which is formed on a corresponding surface of the pair of brake discs, and a fastening portion installed on the wheel and coupled to the slide portion.

[0007] In addition, Patent Publication No. 2010-0076709 discloses a configuration of a brake disc using cast iron containing, by weight percent, carbon (C) 30 to 38, silicon (Si) 20 to 26, manganese (Mn) 03 to 10, phosphorus (P) 001 to 004, sulfur (S) 001 to 012, copper (Cu) 01 to 06, and iron (Fe) 920 to 940.

[0008] And, Patent Publication No. 2005-0006325 discloses a configuration of a disk assembly, and in particular, the configuration is characterized by including a disk body having an inner diameter having a constant radius and an outer diameter forming an outer periphery, and a plurality of fixing holes in which mounting holes are formed that are connected to the inner diameter and the outer diameter and are spaced at constant intervals; a plurality of split pins that are releasable and insertable into the respective mounting holes of the disk body and whose elasticity is adjustable; and a hub body having a bore formed in the center that is fixed to an axle and a mounting groove formed in the periphery into which a portion of the split pin inserted into each mounting hole of the disk body is inserted, and a mounting flange having a fixing hole formed between each of the mounting holes; and a hub cover having a plurality of mounting holes corresponding to each of the mounting grooves of the hub body and accommodating the remaining portions of the split pins, and a plurality of fixing holes that are connected to each of the mounting holes of the mounting flange and are fixed by bolts.

[0009] Meanwhile, the brake system of a high-speed train can be divided into a configuration in which the brake disc is attached to the axle and a configuration in which the brake disc is mounted on the wheel.

[0010] In this case, the brake disc that is connected to the shaft is mostly made in the shape of a disk and can be manufactured using forged steel, so it has the advantage of high rigidity.

[0011] Of course, in order to increase the heat dissipation properties, it is also manufactured using cast steel that forms cooling fins inside the plate.

[0012] The brake disc mounted on the wheel is attached to both sides of the wheel, and in some cases, a number of fins are formed on the part that comes into contact with the wheel to improve heat dissipation characteristics. In cases where cooling fins are formed as described above, they are mostly manufactured from cast steel in consideration of manufacturing cost, which has a somewhat disadvantageous disadvantage in terms of rigidity.

[0013] The present invention has been devised to overcome the shortcomings of the prior art as described above, and aims to provide a method for manufacturing a wheel-mounted brake disc for a railway vehicle, which can realize high rigidity and high heat dissipation characteristics by forming a portion in contact with a brake pad from forged steel and forming a heat dissipation fin in a portion in contact with a wheel using a metal 3D printing method.

[0014] In order to achieve the above object, the present invention provides a method for manufacturing a wheel-mounted brake disc for a railway vehicle, which is mounted on both sides of a wheel of a railway vehicle, comprising: a forging step of forming a base in the shape of a steel plate having a central hole formed in the center thereof by a ring rolling method using a ring rolling device; a first heat treatment step of normalizing the base manufactured through the forging step; a second heat treatment step of performing heat treatment on the base processed through the first heat treatment step through a quenching process and annealing process; a first processing step of performing mechanical processing on the outer surface of the base processed through the second heat treatment process; a first inspection step of performing non-destructive inspection on the internal state of the base manufactured through the first processing step; a cooling fin forming step of forming a plurality of cooling fins on one surface of the base, which is found to be satisfactory through the first inspection step, by a metal 3D printing method, to manufacture the disc; a second inspection step of performing non-destructive inspection on the internal state of the disc manufactured through the cooling fin forming step; And it is characterized by including a second processing step of mechanically processing a disk that has good inspection results through the second inspection step to manufacture it into a final product.

[0015] Preferably, the steel material in the forging step is characterized by including C 0.2 wt% to 0.3 wt%, Si 0.4 wt% to 0.7 wt%, Mn 0.35 wt% to 0.80 wt%, P 0 wt% to 0.03 wt%, S 0 wt% to 0.015 wt%, Ni 0 wt% to 0.5 wt%, Cr 1.0 wt% to 1.5 wt%, Mo 0.7 wt% to 1.3 wt%, Cu 0 wt% to 0.3 wt%, V 0.2 wt% to 0.3 wt%, and Fe 94.255 wt% to 97.15 wt%.

[0016] Preferably, the first heat treatment step is characterized by including a procedure of charging the base at a furnace temperature of 550°C or lower, heating it at a temperature of 200°C / hr or less, heating it at 970°C to 1000°C for 5 to 6 hours, and then cooling it by air cooling.

[0017] Preferably, the metal 3D printing in the cooling fin forming step is characterized by the WAAM method.

[0018] More preferably, the WAAM method is characterized in that multiple layers are laminated in a manner in which one layer is laminated and then ultrasonic peening is performed on the laminated surface.

[0019] Preferably, in the second heat treatment step, the quenching process is characterized by charging the base at a furnace temperature of 550°C or lower, then heating it at 200°C / hr, then heating it at 940°C to 960°C for 45 to 55 hours, and then rapidly cooling it with water, and the annealing process is characterized by charging the base at a furnace temperature of 550°C or lower, then heating it at 200°C / hr, then heating it at a temperature of 620°C to 660°C for 8 to 10 hours, and then cooling it with air.

[0020] Preferably, the secondary processing step is characterized by forming a joining hole in the cooling fin of the disk manufactured through the previous step and cutting both sides of the disk with a predetermined precision.

[0021] Preferably, the forging step is characterized in that, before applying the ring rolling method, the ingot-shaped material is heated to 1200°C to 1250°C, then formed into a billet in the shape of a circular rod, then cut into a plurality of pieces of a certain size, upset, and manufactured into a preset diameter, and then a hole is formed in the center through piercing, and then additionally formed through ring rolling.

[0022] More preferably, the ring rolling is characterized in that the cross-sectional length between the outer diameter and the central hole of the base is formed to be 105 to 120 when the ring rolling is completed, with respect to 100 before the ring rolling, and the thickness is formed to be 100 / 1.3 to 100 / 1.1 after the ring rolling with respect to 100 before the ring rolling.

[0023] The method for manufacturing a wheel-mounted brake disc for a railway vehicle according to the present invention comprises a forging step, a first heat treatment step, a second heat treatment step, a first processing step, a first inspection step, a cooling fin forming step, a second inspection step, and a second processing step, so that the manufactured disc can form a cooling fin of a complex shape by metal 3D printing on a base manufactured based on forging, thereby having the effect of simultaneously having excellent characteristics due to forging and high heat dissipation characteristics due to the cooling fin.

[0024] Figure 1 is a perspective view of a disc manufactured by a method for manufacturing a wheel-mounted brake disc for a railway vehicle according to the present invention.

[0025] Figure 2 is a front view of Figure 1,

[0026] Figure 3 is a process diagram of a method for manufacturing a wheel-mounted brake disc for a railway vehicle.

[0027] Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. When designating components in each drawing, it should be noted that, where possible, identical components will be given the same reference numerals, even if they appear in different drawings. Furthermore, when describing embodiments of the present invention, detailed descriptions of related known structures or functions will be omitted if they are deemed to hinder understanding of the embodiments of the present invention.

[0028] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of embodiments of the present invention. These terms are only intended to distinguish the components from other components, and the nature, order, or sequence of the components are not limited by the terms. When it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but another component may also be "connected," "coupled," or "connected" between each component.

[0029]

[0030] A method for manufacturing a wheel-mounted brake disc for a railway vehicle according to the present invention is for manufacturing a brake disc (100), as shown in FIGS. 1 and 2, wherein the brake disc (100) comprises a base (10) having a circular plate shape and a central hole (11) formed in the center, a plurality of cooling fins (20) formed on one surface of the base (10), and a plurality of coupling holes (21) formed in some of the cooling fins (20).

[0031] The above base (10) is manufactured using forged steel, and one side is made flat because the brake pad comes into contact with it.

[0032] The surface of the above base (10) is the part that comes into contact with the wheel and has multiple cooling fins (20) formed thereon for heat dissipation.

[0033] The above cooling fins (20) are arranged in the same shape in the circumferential direction, and a plurality of different shapes are arranged in the radial direction.

[0034] Some of the above cooling fins (20) have a connecting hole (21) formed into which a bolt for connecting the wheel and the disk (10) on the opposite side is inserted.

[0035]

[0036] The method for manufacturing a wheel-mounted brake disc for a railway vehicle according to the present invention for manufacturing a brake disc (100) as described above is configured to include a forging step (S1), a first heat treatment step (S2), a second heat treatment step (S3), a first processing step (S4), a first inspection step (S5), a cooling fin forming step (S6), a second inspection step (S7), and a second processing step (S8), as shown in FIG. 3.

[0037]

[0038] Each step is explained in detail below.

[0039]

[0040] Forging stage (S1)

[0041]

[0042] The above forging step (S1) is a step of forging a base (10) in the shape of a disc using a steel material prepared in advance.

[0043] The forging applied in the above forging step (S1) is performed by applying a ring rolling method using a ring rolling device. The method has high rigidity against rotation by aligning the crystals in the circumferential direction through a circular rolling method, and in particular, has the characteristics of increasing resistance to brake pads and preventing surface cracks occurring in the radial direction.

[0044] Here, the material of the base (10) is preferably SFCMV1, and the SFCMV1 is composed of C 0.2 wt% to 0.3 wt%, Si 0.4 wt% to 0.7 wt%, Mn 0.35 wt% to 0.80 wt%, P 0 wt% to 0.03 wt%, S 0 wt% to 0.015 wt%, Ni 0 wt% to 0.5 wt%, Cr 1.0 wt% to 1.5 wt%, Mo 0.7 wt% to 1.3 wt%, Cu 0 wt% to 0.3 wt%, V 0.2 wt% to 0.3 wt%, and Fe 94.255 wt% to 97.15 wt%.

[0045] Since the above initial material is in an ingot form, in order to process it using a ring rolling device, the material is first heated to 1200°C to 1250°C in an ingot state, then formed into a billet in the shape of a circular bar, then cut into multiple pieces of a certain size, upset, and manufactured into a preset diameter, and then a hole is formed through piercing in the center, and then the material is placed in a ring rolling device and formed.

[0046] Meanwhile, the forming ratio is set so that the length of the billet is 3.5 to 4.5 times longer than the ingot length when forming from an ingot to a billet, and then the billet is cut to a certain length, and the length of the upsetting is formed to be 100 / 3.6 to 100 / 3.2 for 100 sheared billets.

[0047] Finally, in ring rolling, the cross-sectional length between the outer diameter and the inner diameter is formed to 105 to 120 when ring rolling is completed, with respect to 100 before ring rolling, and the thickness is formed by setting the thickness to 100 / 1.3 to 100 / 1.1 after ring rolling with respect to 100 before ring rolling. In other words, the thickness is formed to be reduced.

[0048] The above molding ratio has the advantage of improving crystal characteristics while increasing the overall process speed, but the molding ratio can be implemented differently if necessary.

[0049] It is preferable that the base (10) manufactured by the above ring rolling device include a margin for subsequent mechanical processing.

[0050]

[0051] First heat treatment stage (S2)

[0052]

[0053] The above first heat treatment step (S2) is a step for performing heat treatment for mechanical processing of the base (10) manufactured through the above forging step (S1).

[0054] Here, the first heat treatment is normalizing, and the processed base (10) is loaded at a furnace temperature of 550°C or lower, heated at a rate of 200°C / hr or less, heated to 970°C to 1000°C for 5 to 6 hours, and then cooled by air cooling.

[0055] At this time, if the heating temperature is less than 960℃, the normalizing effect may not appear, and if it exceeds 1000℃, there is a risk of other transformations occurring, so it is inappropriate. Also, if the heating time is other than 5 to 6 hours, the normalizing effect may not appear.

[0056]

[0057] Second heat treatment stage (S3)

[0058]

[0059] The above second heat treatment process (S3) is a heat treatment process for improving the mechanical properties of the base (10) manufactured through the first heat treatment, and is performed through a quenching process and an annealing process.

[0060] In the quenching process here, the base (10) manufactured through the previous step is charged at a furnace temperature of 550°C or lower, then heated at 200°C / hr, heated to 940°C to 960°C for 45 to 55 hours, and then rapidly cooled with water.

[0061] The above temperature range and time are suitable for quenching steel.

[0062] And the annealing process is also carried out by charging at a furnace temperature of 550℃ or lower, then increasing the temperature at 200℃ / hr, heating at a temperature of 620℃ to 660℃ for 8 to 10 hours, and then cooling in air. Through the annealing process, internal stress, etc. generated by quenching are removed.

[0063] By the second heat treatment step (S3) described above, the internal structure of the base (10) has the advantage of having the specificity of the material crystallization by the forging step (S1) as well as the removal of internal stress, etc., and having appropriate surface hardness and overall strength.

[0064]

[0065] First processing stage (S4)

[0066]

[0067] The above first processing step (S3) is a step for processing the surface of the base (10) for inspection and additional processing, since the base (10) processed through the above second heat treatment process (S3) has completed all heat treatments.

[0068] The above processing is performed by conventional cutting processing, and it is preferable to remove a thickness of about 2 mm using a cutting device, etc., to remove unevenness, etc., of the surface of the base (10).

[0069]

[0070] First inspection stage (S5)

[0071]

[0072] The above first inspection step (S5) is a step for confirming the internal state of the manufactured base (10) through inspection. Here, the base (10) has an appropriate surface state through mechanical processing through the above first processing step (S4), so that non-destructive testing such as ultrasonic testing can be performed.

[0073] In the above first inspection step (S5), internal cracks, etc. of the base (10) are inspected to determine suitability.

[0074] In addition, the first inspection step (S5) is performed on all manufactured bases (10), and if an internal defect is found through the non-destructive inspection, the bases are disposed of.

[0075]

[0076] Cooling fin formation step (S6)

[0077]

[0078] The above cooling fin forming step (S6) is a step of forming a plurality of cooling fins (20) on one surface of the base (10) manufactured through the inspection step (S4) to manufacture a pre-processing disk (100) including a margin for mechanical processing.

[0079] It is preferable that the above cooling fin (20) be formed on one surface of the base (10) using a metal 3D printing method.

[0080] Although many methods have been proposed for the above metal 3D printing method, it is particularly desirable to implement it using the WAAM (Wire Arc Additive Manufacturing) method.

[0081] The above WAAM method uses an arc heat source to weld wire-shaped materials and perform additive manufacturing (AM), and has the characteristic of being able to create a precise, stereoscopic shape by layering the welds one by one in the desired shape.

[0082] Additionally, when laminating layers using the WAAM method, ultrasonic peening can be performed additionally after forming one layer to remove internal stress that may occur due to welding, etc.

[0083] That is, when lamination and ultrasonic peening are performed alternately, there is an advantage in that the internal stress formed in the WAAM can be removed, thereby forming a cooling fin (20) of uniform quality.

[0084] Meanwhile, if the material of the wire is selected to have excellent bonding strength with the base (10), there is an advantage in that a cooling fin (20) of a complex shape can be easily formed.

[0085] In addition, the cooling fin (20) does not require high surface precision except for the area in contact with the wheel due to the heat dissipation characteristics of the disk (100) and the configuration for contact with the wheel, and only a shear force in the lateral direction is applied during the pressing force and braking operation, so even if it is formed using the metal 3D printing method as described above, it has the characteristic of implementing sufficient strength.

[0086]

[0087] Second inspection stage (S7)

[0088]

[0089] The above second inspection step (S7) is a step for inspecting the quality of the disk (100) on which the cooling fins (20) are formed, and the inspection is performed using a non-destructive method.

[0090] In particular, the second inspection step (S7) focuses on inspecting the quality of the cooling fin (20) itself formed through the cooling fin forming step (S6) and the boundary between the cooling fin (20) and the base (10).

[0091] If necessary, the outer surface of the cooling fin (20) can be additionally processed for ultrasonic inspection of the cooling fin (20).

[0092] In addition, the second inspection step (S7) is also performed on all manufactured disks (100), and if an internal defect is found through the non-destructive inspection, the disks are discarded.

[0093]

[0094] Second processing stage (S8)

[0095]

[0096] The above second processing step (S8) is a step in which mechanical processing is performed for the last time on the pre-processing disk (100) manufactured through the previous step.

[0097] First, a plurality of joining holes (21) are formed in the pre-processing disk (100), and then the opposite surface of the pre-processing disk (100) where the cooling fins (20) are formed is precisely machined, and the outer surface of the cooling fins (20) is also precisely machined.

[0098] The above-mentioned joining hole (21) is formed by penetrating the cooling fin (20) and the base (10), and if necessary, an internal section with a relatively large diameter can be formed at both ends of the joining hole (21) so that a bolt head or the like can be installed therein.

[0099] It is preferable that the above precision machining be performed using cutting machining with a precision set in advance.

[0100]

[0101] The disk (100) manufactured through the above steps can form a complex-shaped cooling fin (20) by metal 3D printing on a base (10) manufactured based on forging, so it has the effect of simultaneously having excellent characteristics due to forging and high heat dissipation characteristics due to the cooling fin (20).

[0102]

[0103] Although the present invention has been illustrated and described above with respect to specific preferred embodiments, the present invention is not limited to these embodiments, and includes various forms of embodiments that can be implemented by a person having ordinary skill in the art to which the invention pertains without departing from the technical spirit of the present invention claimed in the patent claims.

Claims

1. A method for manufacturing a wheel-mounted brake disc for a railway vehicle mounted on a wheel of a railway vehicle, A cooling fin forming step for manufacturing a disk by forming a plurality of cooling fins on one side of a base manufactured through mechanical processing based on a base in the shape of a disk using a metal 3D printing method; and A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a post-inspection step of non-destructively inspecting the internal state of a disc manufactured through the above cooling fin forming step.

2. In paragraph 1, The above post-inspection steps are: A step of focusing on inspecting the quality of the cooling fin itself formed through the cooling fin forming step and the boundary between the cooling fin and the base; and A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of additionally processing the outer surface of the cooling fin for ultrasonic inspection of the cooling fin.

3. In paragraph 1, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, further comprising a post-processing step of mechanically processing a disc that has been inspected as having good results through the above post-inspection step to produce a final product.

4. In paragraph 3, The above post-processing steps are: A step of forming a joining hole in the cooling fin of the disk manufactured through the previous step; and A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of cutting both sides of the disc to a predetermined precision.

5. In paragraph 4, The step of forming the above-mentioned joining hole is: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of forming a joining hole that penetrates the cooling fin and the base and forms an internal section at both ends so that a bolt head or the like can be installed therein.

6. In paragraph 1, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, further comprising a forging step of forming the above-mentioned disc-shaped base by a ring rolling method using a ring rolling device.

7. In paragraph 6, The above forging step is, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of forming a base in the form of a disk with a central hole formed in the center thereof using a ring rolling device.

8. In paragraph 7, The above forging step is, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising the steps of heating an ingot-shaped material to 1200°C to 1250°C before applying a ring rolling method, forming it into a billet in the shape of a circular bar, cutting it into a plurality of pieces of a certain size, upsetting it to manufacture it into a preset diameter, forming a hole through piercing in the center, and then additionally forming it through ring rolling.

9. In paragraph 8, The above ring rolling is, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, characterized in that the cross-sectional length between the outer diameter and the central hole of the base is formed to be 105 to 120 when ring rolling is completed, with respect to 100 before ring rolling, and the thickness is formed to be 100 / 1.3 to 100 / 1.1 after ring rolling with respect to 100 before ring rolling.

10. In paragraph 8, The above forging step is, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising the steps of: when forming an ingot into a billet, setting the forming ratio so that the length of the billet is 3.5 to 4.5 times longer than the length of the ingot; and then cutting the billet to a predetermined length, and then forming the billet so that the length of the upsetting is 100 / 3.6 to 100 / 3.2 with respect to the sheared billet 100.

11. In paragraph 1, It further includes a pre-inspection step of non-destructively inspecting the internal condition of the base manufactured through mechanical processing based on a base in the shape of a disc. The above cooling fin forming step is: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of manufacturing a disc by forming a plurality of cooling fins on one surface of a base having a good inspection result through the above-mentioned pre-inspection step using a metal 3D printing method.

12. In paragraph 11, The above cooling fin forming step is: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of manufacturing the disc by forming a cooling fin, which is a component that contacts the wheel of the railway vehicle while performing heat dissipation of the disc, on one side of a base that has a good inspection result through the previous inspection step.

13. In paragraph 11, The above cooling fin forming step is: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of forming a plurality of cooling fins on one surface of a base having a good inspection result through the above-mentioned pre-inspection step using a WAAM-type metal 3D printing method.

14. In paragraph 13, The step of forming by the metal 3D printing method of the WAAM method is as follows: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of stacking a plurality of layers in a manner of stacking one layer and then performing ultrasonic peening on the stacked surface.

15. In paragraph 13, The step of forming by the metal 3D printing method of the WAAM method is as follows: A method for manufacturing a wheel-mounted brake disc for a railway vehicle, comprising a step of welding a wire-shaped material using an arc heat source and performing layer-by-layer welding to create a precise, concise shape.

16. In paragraph 6, A first heat treatment step of normalizing the base manufactured through the above forging step; and A method for manufacturing a wheel-mounted brake disc for a railway vehicle, further comprising a second heat treatment step of performing heat treatment on the base treated in the first heat treatment step through a quenching process and an annealing process.

17. In paragraph 16, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, further comprising a pre-processing step of performing mechanical processing on the outer surface of the base processed through the process of the second heat treatment step.

18. In paragraph 16, The above first heat treatment step is, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, characterized in that it includes a procedure of charging the base at a furnace temperature of 550°C or lower, heating it at a temperature of 200°C / hr or less, heating it to 970°C to 1000°C for 5 to 6 hours, and then cooling it by air cooling.

19. In paragraph 16, A method for manufacturing a wheel-mounted brake disc for a railway vehicle, characterized in that in the second heat treatment step, the quenching process comprises charging the base at a furnace temperature of 550°C or lower, heating it at 200°C / hr, heating it at 940°C to 960°C for 45 to 55 hours, and then rapidly cooling it with water, and the annealing process comprises charging the base at a furnace temperature of 550°C or lower, heating it at 200°C / hr, heating it at a temperature of 620°C to 660°C for 8 to 10 hours, and then air cooling it.

20. In paragraph 1, A forging step in which a base in the shape of a disc with a central hole formed in the center is formed by ring rolling using a ring rolling device; A first heat treatment step of normalizing the base manufactured through the above forging step; A second heat treatment step in which the base treated in the first heat treatment step is heat treated through a quenching process and annealing process; A pre-processing step of performing mechanical processing on the outer surface of the base processed through the process of the second heat treatment step; A pre-inspection step for non-destructively inspecting the internal state of the base manufactured through the above pre-processing steps; and A method for manufacturing a wheel-mounted brake disc for a railway vehicle, further comprising a post-processing step of mechanically processing a disc that has been inspected as having good results through the above post-inspection step to produce a final product.

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