A method for expanding the tread profile of a rail wheel

Abstract

The present invention discloses a method for expanding the tread profile of a rail wheel, comprising the following steps: (1) the thin rim tread profile keeps the inner section of the rim and the outer section of the base point coincident with the initial tread profile; (2) the rim root section of the thin rim tread profile is an arc, and its radius R1 is equal to the initial tread profile; (3) the taper influence section of the thin rim tread profile extends toward the rim as the rim thickness decreases; (4) the transition section radius R2 of the thin rim tread profile is equal to the initial tread profile, and the center of the circle is closer to the rim than the transition section center of the initial tread profile; (5) the rim outer section of the thin rim tread profile is obtained by moving the rim outer section of the initial tread profile in a section plane parallel to the radial and axial directions. The present invention enables a wheel with a pseudo-thickening phenomenon of rim thickness to obtain a longer turning and repairing interval, and enables a wheel with a severely worn rim thickness to be restored to a reasonable thickness instead of necessarily the initial tread, thereby obtaining a longer wheel service life.

Description

Technical Field

[0001] The invention relates to a method for expanding the tread profile of a rail wheel, belonging to the technical field of rail wheels. Background Art

[0002] Equivalent taper is an important parameter in wheel-rail matching. When parameters such as track gauge and wheelset inner distance are determined, the equivalent taper mainly depends on the wheel tread shape and rail profile. The size of the equivalent taper is closely related to the dynamics of the railway vehicle. If the equivalent taper is too small, low-frequency shaking may occur during the operation of the railway vehicle, and if the equivalent taper is too large, the lateral vibration of the railway vehicle frame may be too large.

[0003] The new locomotive and vehicle have verified the matching of the initial tread shape with the rail through dynamic type tests. However, the wheel tread needs to be repaired due to wheel tread wear during use. When the wheel flange thickness increases or the wheel flange thickness wears more, the wheel should be repaired with a thin wheel flange tread shape to obtain a longer repair interval and a longer wheel service life. However, improper use of a thin wheel flange tread shape may lead to changes in the equivalent taper, thereby affecting the stability of the train operation. Summary of the invention

[0004] In order to avoid the shaking or vibration of the rail vehicle caused by the unreasonable thin wheel flange tread shape, which affects the dynamic performance of the rail vehicle, a method is needed to expand a series of thin wheel flange thickness tread shapes that are beneficial to maintaining the running stability of the vehicle based on the initial tread shape that has been verified to have good running stability of the vehicle. The present invention provides a method for expanding the tread shape of a rail wheel, and the specific technical solution is as follows.

[0005] A method for expanding the tread profile of a railway wheel, characterized in that the initial tread profile of the railway wheel comprises a rim inner section, a rim outer section, a rim root section, a transition section, a taper influence section, and a base point outer section connected in sequence, wherein the taper influence section and the base point outer section are separated by the base point, and the rim inner section and the rim outer section are separated by the rim vertex; the profile expansion method mainly comprises the following steps:

[0006] (1) The thin rim tread profile keeps the inner section of the rim and the outer section of the base point coincident with the initial tread profile;

[0007] (2) The flange root section of the thin flange tread profile is an arc, and its radius R1 is equal to the initial tread profile. The flange thickness measurement point is always on the flange root section; the flange thickness measurement point is the point where the flange root section deviates from the base point along the radial direction of the rail wheel by a distance h;

[0008] (3) The tapered influence section of the thin rim tread shape extends toward the rim as the rim thickness decreases, and its radius remains unchanged;

[0009] (4) The radius R2 of the transition section of the thin rim tread profile is equal to that of the initial tread profile, and the center of the circle is closer to the rim than the center of the transition section of the initial tread profile. The axial distance from the center of the transition section of the thin rim tread profile to the base point is L2', and the axial distance from the center of the transition section of the initial tread profile to the base point is L2. The difference ΔL2 between L2' and L2 is positively correlated with the difference ΔSd in rim thickness, ΔL2 = k*ΔSd. The rim thickness is the axial distance from the rim thickness measurement point to the inner end face of the rail wheel. The rim thickness of the initial tread profile is Sd, and the rim thickness of the thin rim tread profile is Sd'. The difference ΔSd in rim thickness is the difference between Sd and Sd'.

[0010] (5) The outer rim section of the thin rim tread shape is obtained by moving the outer rim section of the initial tread shape in a section plane parallel to the radial and axial directions. The rim vertex of the thin rim tread shape is the intersection of the inner rim section and the outer rim section, which is not a tangent point.

[0011] It should be noted that the thin-rim tread shape refers to the tread shape after the tread shape of the rail wheel is expanded, and the initial tread shape and the thin-rim tread shape refer to the shape of the rail wheel in a section plane parallel to the radial and axial directions.

[0012] Furthermore, the extension length of the taper influencing section from the base point to one side of the wheel rim is not less than 5 mm.

[0013] Furthermore, the radius R1 is 12 to 20 mm.

[0014] Furthermore, the h is 10 mm.

[0015] Furthermore, the rim root section, transition section and taper influencing section are tangentially connected in sequence.

[0016] Furthermore, the outer side of the base point outer segment also has a chamfer.

[0017] Furthermore, k takes a value of 1.3 to 1.8.

[0018] Further, the outer section of the wheel rim includes a straight section, and the straight section is tangentially connected to the root section of the wheel rim. Preferably, the slope and length of the straight section of the thin wheel rim tread profile are the same as those of the initial tread profile.

[0019] According to the shape expansion method provided in the present invention, a series of thin rim thickness tread shapes that are beneficial to maintaining the vehicle's running stability can be expanded based on the initial tread shape that has been verified to give the vehicle good running stability. By using these thin rim thickness tread shapes to repair wheels, wheels with false thickening of the rim thickness can have longer repair intervals, and wheels with severely worn rim thickness can be restored to a reasonable thickness rather than necessarily the initial tread, thereby obtaining a longer wheel service life without affecting the train's running stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of the initial tread profile of the present invention;

[0021] Figure 2 It is a schematic diagram of the tread shape before and after expansion.

[0022] In the figure: rim inner section 1, straight section 2, rim outer section 3, rim root section 4, transition section 5, taper influence section 6, base point outer section 7, chamfer 8, rim vertex C, base point O, rim thickness measurement point J. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0024] See also Figure 1-Figure 2 , ABCDEFGOHI is the initial tread profile α, and its rim thickness is Sd, wherein the initial tread profile α includes the rim inner section 1 (AC), the rim outer section 3 (CE), the rim root section 4 (EF), the transition section 5 (FG), the taper influence section 6 (GO), the base point outer section 7 (OH) and the chamfer 8 (HI) connected in sequence, the taper influence section 6 and the base point outer section 7 are separated by the base point O, and the rim inner section 1 and the rim outer section 3 are separated by the rim vertex C. In order to obtain a thin rim tread profile β with a rim thickness of Sd', the profile expansion method mainly includes the following steps:

[0025] (1) Keep the arc OH, chamfer HI and the inner section ABC of the rim unchanged;

[0026] (2) The radius R2 of the new transition arc F'G' is equal to that of the initial tread. The difference between the axial (x direction) distance L2' from the center O_R2' to the tread base point and the initial tread L2 is ΔL2=L2'-L2=k*ΔSd, where k is 1.3-1.8. According to the axial position of the center O_R2' and the radius R2, F'G' is made tangent to the taper influence section G'O. G'O is obtained from the taper influence section GO of the initial tread profile α toward the wheel rim. The extension length L1 of the taper influence section from the base point to the wheel rim side is not less than 5 mm.

[0027] (3) Through the new rim thickness measurement point of the rim, make a new rim root segment arc E'F' with a radius R1 equal to the initial tread profile, tangent to the arc F'G';

[0028] (4) The outer rim section CE includes a straight line segment DE, and a new straight line segment D'E' is made tangent to the arc E'F', and the slope and length are the same as the straight line segment DE of the initial tread profile;

[0029] (6) The arc DC of the outer segment of the wheel rim is translated from point D to point D', and intersects with segment BC at point C'. Point C' is the new vertex of the wheel rim.

[0030] (7) The rim vertex C' of the thin rim tread profile is the intersection of the rim inner section AC' and the rim outer section C'E', which is not a tangent point;

[0031] (8) AB-C'-D'-E'-F'-G'-OHI is the thin rim tread profile β with the expanded rim thickness Sd' ( Figure 2 2). By the same method, the thin rim tread profile γ(ABC”-D”-E”-F”-G”-OHI) with a rim thickness of Sd” can be obtained again.

[0032] The flange thickness measurement point J is a point at which the flange root section 4 deviates from the base point O by a distance h in the radial direction (y direction) of the rail wheel. The distance h is preferably 10 mm.

[0033] The embodiments of the present invention are described above in conjunction with the accompanying drawings. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention is not limited to the above-mentioned specific implementations, which are merely illustrative and not restrictive. Under the enlightenment of the present invention, those skilled in the art can also make many forms without departing from the scope of protection of the present invention and the claims, all of which belong to the protection scope of the present invention.

Claims

1. A method for expanding the tread profile of a railway wheel, characterized in that: The initial tread profile of a rail wheel comprises a rim inner section (1), a rim outer section (3), a rim root section (4), a transition section (5), a taper influence section (6), and a base point outer section (7) which are connected in sequence, wherein the taper influence section (6) and the base point outer section (7) are separated by a base point (O), and the rim inner section (1) and the rim outer section (3) are separated by a rim vertex (C). The profile expansion method mainly comprises the following steps: (1) the thin rim tread profile keeps the rim inner section (1) and the base point outer section (7) coincident with the initial tread profile; (2) the rim root section (4) of the thin rim tread profile is an arc, the radius R1 of which is equal to the initial tread profile, and the rim thickness measurement point (J) is always on the rim root section (4); the rim thickness measurement point (J) is a point of the rim root section (4) that deviates from the base point (O) along the radial direction of the rail wheel by a distance h; (3) The tapered section (6) of the thin rim tread shape extends toward the rim as the rim thickness decreases, and its radius remains unchanged; (4) The radius R2 of the transition section (5) of the thin tread profile is equal to that of the initial tread profile, and the center of the circle is closer to the rim than the center of the transition section (5) of the initial tread profile. The axial distance from the center of the transition section (5) of the thin tread profile to the base point (O) is L2', and the axial distance from the center of the transition section (5) of the initial tread profile to the base point (O) is L2. The difference ΔL2 between L2' and L2 is positively correlated with the difference ΔSd in rim thickness, ΔL2=k*ΔSd; the rim thickness is the axial distance from the rim thickness measurement point (J) to the inner end face of the rail wheel. The rim thickness of the initial tread profile is Sd, and the rim thickness of the thin tread profile is Sd'. The difference ΔSd in rim thickness is the difference between Sd and Sd'. (5) The outer rim section (3) of the thin rim tread profile is obtained by moving the outer rim section (3) of the initial tread profile in a section plane parallel to the radial and axial directions. The rim vertex (C) of the thin rim tread profile is the intersection of the inner rim section (1) and the outer rim section (3), which is not a tangent point.

2. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The extension length of the taper influencing section (6) from the base point (O) to one side of the wheel rim is not less than 5 mm.

3. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The radius R1 is 12 to 20 mm.

4. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The distance h is 10 mm.

5. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The rim root section (4), transition section (5) and taper influencing section (6) are tangentially connected in sequence.

6. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The outer side of the base point outer section (7) also has a chamfer (8).

7. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The value of k is 1.3 to 1.

8.

8. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The wheel rim outer section (3) comprises a straight line section, and the straight line section is tangentially connected to the wheel rim root section (4).

9. A method for expanding the tread profile of a railway wheel according to claim 1, characterized in that: The slope and length of the straight line segment of the thin flange tread profile are the same as those of the initial tread profile.

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