CZ20003334A3 - Improved bolster land arrangement for a railcar truck - Google Patents

Abstract

A railway bogie assembly has an arrangement for constraining the free travel clearance between the mated bolster and side frame at the side frame window, and more particularly for reducing or eliminating the clearance or separation gap between the bolster lands and the side frame column wall at the outer edges of the bolster lands and the column wall for reduction of bogie warping during service. <IMAGE>

Description

Improved pViOOO-333k rail vehicle chassis support

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Technical field

The present invention relates to an improved device for rail vehicle chassis surfaces and is a continuation and integral part of U.S. Pat. No. 09/136, 911, mentioned below.

Furthermore, the invention relates to railway vehicle bogie assemblies, in particular to the areas between the side frames and the beam of the railway vehicle bogie assembly. Specifically, in each side frame crossing with a beam adjacent to the friction pad interface, the adjacent positions are mounted with a gap of less than 0.4 inches. The installation of the chassis with this limitation provides a reduction in the chassis deformation and the consequent improvement in swiveling and cornering during operation. However, it also causes frequent wear on the side frame post and the deer stop surface causing wear and tear.

In earlier railway vehicle chassis assemblies, wide laterally extending surfaces of the stopper or surfaces adjacent to the side frame friction plate have been incorporated to prevent beam rotation about its longitudinal axis, and the beam friction shoe pocket has been incorporated to prevent beam rotation about its longitudinal axis. . In rail vehicle assemblies, each side frame has a longitudinal axis parallel to the longitudinal axis of the bogie that intersects and is perpendicular to the longitudinal axis of the beam at the folded position. The rotation of the beam about its vertical axis causes the angular deflection of the longitudinal axes of the side frame and the beam from a perpendicular state in the collapsed state, and this activity is considered a bogie deformation. In the case of rail vehicle bogie deformation, a larger gap between the side frame and the beam at their crossings worsens the bogie deformation, causing the wheel profile to strike the rail at a relatively acute angle when cornering, thereby creating excessive lateral forces. Furthermore, if the gap between the side frame and the beam is too large, the bogie / chassis assembly may be increased.

The bogie of a railway vehicle bogie is a constant instability of a railway vehicle wheelset where the bogie abuts the rail in an oscillating manner, usually with the wheel profile impinging on the rail, causing wheel seizing and generating lateral forces on the rail. A similar condition called 'diamond' is where the side frames and the beam do not form a square and occur when the side frames remain operationally parallel, but one of the side frames moves slightly forward; such a condition is also called paralelograming or

deformation. The deformation results in wheel deflection with respect to the rails; this is more pronounced on a curving track and usually it provides the opportunity for the occurrence of a large angle of attack. The displacement or rotation of the beam about the vertical axis of the beam, which is accompanied by a deflection of its longitudinal axis relative to the side frame, is an indication of the deformation of the rail vehicle bogie. The concept of bogie oscillation, that is, the dynamic instability of the wheelset of a railway vehicle at high speed, is shown by parallelogram or "diamond" bogies. Furthermore, the bias of the bogies is also due to insufficient deformation stiffness.

Wide stop surfaces on the beam surfaces have been provided to prevent rotation of the beam in the side frames and to avoid problems with rotation of the beam about its longitudinal axis; for proper functioning of the surfaces after casting and to prevent wear or damage to the edges of the contact surfaces between the beam and the columns of the beam holes in the side frames.

Earlier practices of narrow-surface structures with wide gaps between beam and side frame surfaces, pillar surfaces are disclosed in U.S. Pat. No. 2,378,415 to Light. In this patent, the outer and inner guide rails on the beam are used to connect to the inner and inner surfaces of the adjacent post. The outer guides of this structure have a smaller depth than the widened portion of the beam opening. The same arrangement of guide rails is disclosed in U.S. Pat. No. 2,422,201 to Lehrman. These significant distances between the side frame column and the beam are clearly discernible in the drawings and figures of these patents.

A technical study on the number of derailments of railway vehicles between 1988 and 1992 was carried out by a team composed of representatives of five railways, three manufacturers of railway vehicles, three manufacturers of railway bogies, major carriers, major fleet owners as well as suppliers of other components and technical consultants. The team was to identify the cause of the derailment and recommend a long-term and short-term solution to prevent derailment. The results of this study are set out in the Final Test, Evaluation and Recommendations for Arc Passing from 125T DS Cars from Rail Sciences Inc. (RSI), Atlanta, Georgia, February 12, 1993. One of the parameters considered for the bogies was to reduce deformation and the research found that one of the five concurrent derailment factors was “side frame-beam deformation due to low reduction of bogie deformation '. One of the subsequent long-term proposals based on the test results was • · • ·

• Develop and use chassis firming techniques. The main discovery of the study was that frame reinforcement devices increase chassis deformation reduction and reduce lateral forces when cornering. Furthermore, it was deduced that the derailments studied were caused by strong lateral forces in the low rail or by an increase in the overall position that allowed the wheelset to engage. One of the reported causes of these large lateral forces was the deformation of the side-frame combination due to the low limitation of the chassis deformation caused by the presence of the triple washers of the bearing adapter and the absence of a wedge that prevents friction.

In this study, a number of other findings and results were noted in this report, yet the present invention addresses only the limitation of bogie deformation of railway vehicles.

U.S. Pat. U.S. Patent No. 4,274,340 to Neumann et. al. specifically, it refers to a friction device with internal and external guide rails that are concave to improve the prevention of displacement of the beam and maintain control of the beam. There is no other known concave structure element in the friction shoe pocket and beam end device.

A smaller gap between the contact surfaces results in greater friction and wear between the surfaces during operation of the bogie of the railway vehicle. The wear of the beam column stop surface is the result of this contact, as well as the ongoing effort to reduce the bogie swing and deformation of the railway vehicle. Restricting or detaining the rail vehicle chassis creates more contact and wear. Therefore, railway undercarriage suppliers are constantly looking for methods and components to reduce the wear of the undercarriages and undercarriage components to increase their service life with better operating performance.

SUMMARY OF THE INVENTION

The above drawbacks are largely overcome by the improved rail vehicle chassis surface arrangement of the present invention, which provides a beam surface structure for rail vehicle chassis assembly beams, the surface structure being flame cured to increase the surface hardness of the contact surface. Specifically, the surface is provided with a contact surface having a Brinell hardness of between about 375 BHN and 515 BHN with an effective hardness depth of about 0.12 inches, such hardness being significantly higher than the cast steel of 137 BPIN to 208 BHN steel specified by AAR • ·

M-210 B + quality. The resulting beam surface provides a significant increase in wear of the beam contact surface when contacting the side frame or friction plate contact surface usually mounted on the column surface. This wear reduction is further increased when the hardened friction plate is mounted on the column friction surface and meets with the contact surface of the beam. Although the increased hardness is directly reflected in the improved durability of the beam or contact surface space, another benefit or result of the improved durability is an improvement in wear of the friction shoe and an increase in the life of the friction shoe.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an oblique view of an exemplary three-piece rail vehicle chassis assembly; FIG. 2 is an enlarged oblique view of a partial cross-sectional view of a side frame and beam connection in FIG. and Figure 3 is a plan view of the side frame and beam joining in a basic position at normal storage; and Figure 3A is a plan view of the side frame and beam joining the column and beam wall contact surfaces, and finally Figure 4 shows a plan view of the side frame joining. 3 and wherein the beam and the side frame are axially deflected from the home position. Figure 5 is a partial cross-sectional plan view of a portion of the side frame and beam cross-over prior to wide fit. Figure 6 is a vertical projection of the side frame column as shown in Figure 5. Figure 7 is a side vertical projection of the interface between the friction plate on the side frame column of the friction shoe. Figure 8 is a side view of a portion of a beam with a concave central portion. Figure 9 is a front vertical projection of a trunk section of a three-piece railway chassis with flame hardened parts; and Figure 10 is a plan view of a three-piece railway vehicle chassis in a normal position at normal loading, showing different moments and forces acting on such a bogie assembly.

DETAILED DESCRIPTION OF THE INVENTION

The rail vehicle bogie assembly in Figure 1 is the basic three-piece bogie assembly for freight railway vehicles. The assembly has a first side frame 10, an expensive side frame 14, and a beam 16 extending between the center holes 18 and 20, these holes 18, and located between the front side frame column 17 and the rear side frame column 19 of the beer and expensive side frame respectively. 12 and 14. In Figure 1, the longitudinal axis 34 of the railway vehicle is horizontal with both the longitudinal axes 36 and 38 of the first and expensive side frames. The longitudinal axis of the beam 40 is generally perpendicular to the axis of the railway vehicle 34 and the longitudinal axes of the side frames 36 and 38 in the basic as-mounted position of the railway vehicle. The beer axle and wheelset 22 and the expensive axle and wheelset 24 are guided between the side frames 12 and 14 at opposite front ends 26 and rear ends 28, respectively, whose side frames 12 and 14 are generally parallel in the basic as assembled state. The beer end of the beam 30 is housed in the opening of the first side frame 18 and the expensive end of the beam 32 is housed in the opening of the expensive side frame 20.

The connection of the beam 16 in the holes 18 and 20 is configured equally for the side frames 12a

Therefore, the following description describes the connection of the beer end of the beam 30 and the opening of the beer side frame 18, but this description is also applicable to the connection of the expensive end of the beam 32 in the opening of the expensive side frame 20. The opening 18 and the beer end of the beam 30 are shown. 2, with partial cross-section, have the beams 42 and 44 revealed between the guide rails 50 and 52. The friction shoe pockets are located in the beam columns 42 and 44 with the friction shoes 46 and 48 at each end. and the rear side of the beam 16 longitudinally positioned the friction shoe and friction shoe pockets 46 and 48 as well as the beam columns 42 and 44 and the tulle beam columns also provide the space 96 shown in Fig. 3A. Since the beam columns 42, 44 and the friction shoe pockets 46, 48 are identical at each end of the beam, only one arrangement will be described, but this description will be applicable to different sets of friction shoe and friction shoe pockets and beam column 42, 46 and 44, 48 The guide rails or projections of beam 50 and 52 on pebbles 2 and 5 extend from the side wall of beam 54 and are arranged outside and inside respectively on both the front and rear pillars of beam 42 and 44, the guide rails 50 and 52 function to maintain position of the side frame between each side of the beam 16 and each side frame 20. Although the guide bars 50 and 52 are shown as relatively independent beers, these elements may be cast or formed as enlarged projections of the beam

16.

The general configuration of the friction shoe 48 in the friction shoe pocket in the beam column 44 is more clearly shown in the section in FIG. 7 with the wall of the beam 60 near the inclined surface of the friction shoe

• · ·· ····

62. The side frame pillar wall 66 has a friction plate 68 with the friction surface of the vertical wall 70 serving to contact the vertical surface 72, the vertical wall of the friction shoe 73.

3A and 5. In Figure 3A, the distance of the guide bars 86 is meant between the side frame column side 66 and the beam column wall 54, and in Figure 5, the distance 86 is thought between the space 96 on the beam column 54 and side surface area 92 of the side frame 94. Particular alignment may vary depending on the design of the beam post and side frame post assembly ⁷ . However, the spacing of the guide rails is generally about 3/8 inch to about 1 inch on the subject chassis assembly of the railway vehicle.

On a particular rail vehicle chassis assembly prior to assembly in Figure 5, the spacing of the guide rails 86 between the projections 94 and the sidewall of the beam 54. However, in the structure of Figure 5, the projections 94 have a longitudinal width much greater than the previous assemblies. as a large-scale assembly. This large-area structure was intended to reduce the rotation of the beam about the longitudinal axis of the beam 40 to the side frame and to reduce the wear of the side frame and beam surfaces that meet during operation. In this structure, the surfaces 92 of the surface 94 were to contact the surfaces 96 of the beam 16. The surfaces 94 were extended by projecting the side frame column 12 with the surfaces 92 closely adjacent or the surfaces 96, the column 54, the beam 16 with gap defining guides.

The axial deflection of the side frame 12 and the beam 16 is shown in Fig. 4. On one measured assembly, this axial deflection was recorded as 1.54α. During operation, the bogie of the railway vehicle 10 is deflected from its reference position with the longitudinal axes 38 of the side frame 12 perpendicular to the longitudinal axis 40 of the beam 16. The axial bias was termed the deformation of the bogie of the railway vehicle. The forces affecting or acting on the deformation properties are shown in FIG. 10 as various arrows, where the torque is recorded in the beam torso region, the lateral forces act at the end of the beam, and the longitudinal forces induce control moments.

On pebble 3, the interface between the contact surfaces of conventional or large-area constructions or rotary barriers is indicated when in contact with each other or at a negligible distance 86. Such proximity to the surfaces at beam interface 16 and side frame 12 or beam columns has been found to reduce or improve deformation of the assembly chassis

In this figure in Fig. 3, the distance 86 has been closed for direct contact of the friction plate 68 and the space 96 on the beam 16. The spaces 96 are formed on the surface adjacent to the pockets of the friction shoe. In this figure, the friction plate 68 extends across the wall width of the side frame post 66. However, it is noted that projections or spaces 94 are located on each side of the friction plate 68 in Figure 5 and the space or front 92 of these spaces may be parallel to the surface 70 friction plates 68.

Figure 3A shows a beam post wall or guide surface 96 as a continuation between guide rails 50 and 52. In the same way, the vertical walls 66 of the side frame post are all recorded as a single vertical wall. The use of friction shoes and friction pockets was omitted from this illustration. A further improvement of this illustration is that the vertical surfaces 66 and 96 may be hardened surfaces.

Although the surface of the friction plate 70 in Figures 5 and 7 is shown in contact with the surface 96 in Figure 3, tests have shown that the angle control between the beam 16 and the side frames 12 or 14 can be adjusted at guide rail distances of less than four tenths ( 0.40) inches closer to fifteen thousandths (0.015) inches. In a rail vehicle chassis experiment with the necessary reduction in guide bar distance 86, deformation or lateral stability of the chassis that met the stability criteria of AAR Chapter XI (0.26 effective G value at 70 miles per hour) for the Super Service Ridemaster® Double Chassis was maintained cylindrical side bearings, as well as another permanent contact chassis assembly (CCSB). Tilt control - deformation of the bogie assembly by increasing deformation stiffness improves lateral stability and reduces lateral cornering forces at the wheel / rail interface and thus improves the functional characteristics of bogie assemblies during pivot and cornering, especially for freight rail vehicles, flatbed trucks with front walls. Limiting the spacing of the guide rails minimizes or limits the allowable deformation angle to an axial deflection of between about 0.1 ° (1.7 millirads) and 2.0 ° (35 millirads). All of these attempts to control bogie deformation or oscillation have resulted in increased wear on the contact surfaces of the side frame posts and the contact surfaces of the beam.

· ~ 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 ~ ···

In Figure 8, the beam surface or contact surface 96 is shown in a side view with an upper edge 110, a lower gate 112, and an inner guide rail 50. Nevertheless, the contact surface 96 has an arcuate or concave shape. The projected planar surface is indicated by a dashed line 114, but as already indicated, the surface 96 comprises an upper conical surface 116, a lower conical surface 118, and a middle surface 120. The conical surfaces 116, 118 extend from the upper surface 110 and lower surface 112 respectively. the central surface 112. The conical surfaces 116 and 118 may be of the same length, but this is not necessary. Further, in Figure 8, the tapered surfaces 116, 118 are longer than the straight portion 120, as shown in the Figure. The specific inclination of the surfaces 116 and 118 allows limited movement between the side frame and the beam 16 in the pockets of the beam.

The structure of the poured beer ensures that the side frame moves towards the beam. Failure to provide at least a nominal degree of clearance for movements between the side frame and the beam would prevent the side frame from following the vertical movements of the wheelset while the railway vehicle is being driven. Under extreme conditions, the wheelset 22 or 24 could potentially literally fall out of the jaws of the pedestal at the front end 26 or the rear end 28. The relative degree of movement or movement between the beam and the side frame allows movement between the beam and the side frame. This concern was analyzed by an empirical test where the load was removed from one of the wheels of the chassis assembly 23 to analyze the effect on the remaining wheels of the chassis assembly 10.

The primary contact between the beam space 96 and the contact surface of the side frame post 92 or the friction plate 68 on the post surface 92 is supported by the central and straight segment 120. Although noted in a flat configuration, it has been found that segment 120 can be contoured or oval and therefore, equality 120 is not a limitation. In Figure 8, the concave central surface 120, which may also be flat as noted, was cured by a flame curing process to raise its temperature to a transformation temperature, and then the surface was quenched by quenching. The resulting surface hardness of the hardened area is between 375 BHN and 515 BHN of the Brinell hardness scale. This is significantly higher than in the cast region of the conical regions 116, 118, which are typically in the range of 137 BHN to 208 BHN for the steel specified by AAR M-210 B + grade. While it is preferred to cure only the local area 120, it is recognized that the entire length of the space 96 could be cured. It is further recognized that the area could be cured by alternative methods such as induction cure or hard layer acquisition by a process such as spraying. flame. The above condition shall include deviations for dimensional changes. It is further recognized that other base materials such as AAR, grades B and C, can be used in the manufacture of the beam or side frames and cured in the same manner.

In Figure 9, it is shown that the two concave sections 120 of each pocket of the cantilever cure are cured in the width of the contact surface 96. With this increased hardness, the wear rate of the concave section 120 is reduced when friction with the friction plate 68 or the contact surface of the post 66. The friction plates 68 have a Brinell hardness of approximately 400 BHN, therefore the wear rate of the plate 68 and the concave section 120 is now relatively equivalent and of higher hardness, instead of the high hardness plate 68 rubbing against the soft surface of the concave section 120 as cast.

Further, the increased life of the concave section 120 helps to reduce the overall load and consequent wear of the friction shoe, such as the shoe 46, in the beam pocket by maintaining a condition corresponding to the friction plate 68.

Figure 7 shows the oval or concave shape of the friction shoe and the pocket pocket. However, the concave region 120 of the vertical contact surface of the beam is more clearly shown in FIG. 8. In this figure, the beam space or contact surface 96 has a generally centrally located region 120 concave from the base surface 96 indicated by a partial dashed vertical line 114. an area 96 of less than one third of the total length of the beam space 96.

In Figure 9, the pockets of the beam with the friction shoe 46 and surfaces 96 are recorded in a front vertical projection with both the contact surfaces 96 and the friction shoe 46. It is noted that the front side of the friction shoe 72 meets the surface of the post 70 on the friction plate 68 as shown. Figure 5. In these figures, a given rail vehicle chassis structure structure is specified by the Association of American Railroads AAR as a steel alloy with AAR specification M-210, B + grade with Brinell hardness in cast state between 137 BHN and 208 BHN.

The flame curing process can utilize natural gas, acetylene or other high temperature generating gas. The area 120 of each beam pocket is heated to the transition

A temperature of about 1700 ° F and then quenched by quenching to maintain hardness and sub-mirror microstructure. Although the depiction of the hardness zone in Fig. 8 is made at a uniform depth, it is recognized that there is a transition between surface and subsurface hardness, which must be within said hardness range.

In the present case, the effective hardness was measured to a depth of at least 0.12 inches while providing at least 300 BHN at that depth. This is an increased hardness range to ensure that the surface hardness will better withstand frictional wear by contact with the contact surface of the post 66 or the friction plate 68, where the friction plate 68 is known to have a hardness of about 400 BHN. The area of the beam surface is an additional member of the cushioning structure of the friction cushion and preventing its premature wear by contact with a harder and therefore more aggressive surface increases the service life of the cushioning structure.

While only specific illustrations of the invention have been described and shown, it is understood that various modifications and modifications thereof may be made. Accordingly, it is intended that the appended application cover all such modifications and adaptations as may fall within the scope and spirit of the present invention.

Claims (10)

PATENT CLAIMS 1. An improvement / arrangement of a rail vehicle chassis surface comprising: a beam (16) of a first side frame (10), an expensive side frame (14) and a longitudinal axis (34) of a chassis and a beam pillar stop so wherein each of said first and expensive chassis side frames (10, 14) has an aperture (18) and (20) that are disposed between a front side frame post (17) and a rear side frame post (19), respectively. an expensive side frame (12,14) and each of said front posts having a front post surface and a post stop surface, and each of said rear posts having a rear post surface and a post stop surface, said beam (16) having a first end, an expensive end, a front side of the beam with a beam stop surface at each of said first and second ends, a rear side of the beam (16) with a beam stop surface at each of said first and expensive ends and a longitudinal axis of the beam, one of said beam ends, first or expensive connected to an opening (18, 20) in the beer or expensive side frame (17, 19) and expensive from the first or expensive end of the beam (16) to the opening (18, 20) in expensive expensive side frames (17, 19), beer and an expensive and said front side of the beam and a rear side of the beam near said ends of the beam, first and second, to the surface of the front post and the surface of the rear post in said or joined holes in the beer and expensive side frame (17, 19) and said side frame post stop surfaces (17, 19) at said front and rear pillar surfaces in proximity to said beam stop surfaces, wherein the beam stop surfaces (16) ) may contact or approach said surfaces of the side frame post stop to maintain control of the deformation angle between said end of the beam (16) and said side frame (17) during a bend of the rail vehicle chassis assembly for use of said rail vehicle chassis and a beer and expensive side frame (17, 19) to reduce the pivot assembly of said railway vehicle bogie, wherein said beam post stop surface is flame cured to increase the hardness of said beam post stop surface. 9 9 9 9 9 9 99 9 9 9 9 • · ··· 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 99,999 99,999 99,999 2. The improved rail vehicle chassis surface device of claim 1, wherein the beam column stop surface for the rail chassis assembly beam is hardened to a depth of between 375 BHN and 515 BHN in depth. about twelve thousandths of an inch below the abutment surface. 3. The improved beam surface device for a railway vehicle chassis assembly according to claim 1, wherein said stop beam for engaging a side frame post stop surface in operation is said casting beam stop surface having a surface hardness in a range of 137 BHN to 208 BHN, wherein the beam stop surface may be in contact with the beam stop surface, said beam stop surface being flame cured to increase surface hardness to a hardness in the range 375 BHN to 515 BHN to reduce wear on said beam stop surface in contact with the column stop surface to increase the life of the beam stop surface. 4. The improved beam surface apparatus for a railway vehicle chassis assembly according to claim 1, wherein the beam stop surface of the beam for the railway vehicle chassis assembly wherein said beam has a stop surface for engaging a side frame column stop surface, said stop surface. the beam is flame hardened to between 375 BHN and 515 BHN to reduce the wear index between said side frame column (17, 19) and beam stop surfaces and maintain smaller gaps between said stop surfaces to increase deformation stiffness and reduce instability of said chassis assembly at high speeds during the life cycle of said chassis assembly. An improved beam surface device for a railway vehicle chassis assembly according to claim 1, wherein the beam column stop surface for the railway vehicle chassis assembly with a beam, a beer side frame (17), a second side frame (19) and a longitudinal axis (34) of the chassis, further comprising a plurality of friction shoe pockets (42,44), friction shoes (46,48) secured to each of the abutted pillar stop surfaces, the beam stop surfaces operable to contact the at least one abrasive shoe; a side frame post stop surface during operation of said chassis assembly, and each said beam has an upper side and a bottom side, each stop surface of said ·· φφ 9 · 1 < · • * * φ * φ Φ · Φ · ΦΦ Φ ΦΦΦ 9 * · Φ • 9 9 Φ 9 · · 13 · Φ φφ ΦΦΦΦ - 13 the beam has a concave region generally centrally located on said beam stop surface between said upper side of the beam and said lower side of the beam, said concave region being cured to about 375 BHN to 515 BHN to increase the durability of said beam a concave region, said concave region operable to contact at least one of said side frame post stop (17) and friction shoes (46, 48) on said post stop surface. 6. An improved beam surface apparatus for a railway vehicle chassis assembly according to claim 1, wherein the beam post stop surface for the railway vehicle chassis assembly with the beam (16), the beer side frame (17), a second side frame (19) and a longitudinal axis (34) of the bogie, further comprising a plurality of friction shoes (46,48), a friction plate (42,44) secured to each of the column stop surfaces and the beam stop surfaces functioning to contact at least one of the pockets a friction shoe (46,48) and a side frame post stop surface during operation of said chassis assembly, each said beam post stop surface having a friction shoe pocket (46,48), an inner stop surface and an outer stop surface, each of said inner surfaces and the outer stop has a concave region generally centrally located on the stop surface of said beam, said concave region functions for contacting at least one of said side-frame post-stop surfaces (17,19) and friction shoes (46,48) on said post-side post-stop surface to prevent undercarriage swing and allow limited general vertical movement of said beam stop surfaces relative to said side frame stop surfaces ( 17 and 19). A beam post stop surface for a railway vehicle bogie assembly with a beam, a beer side frame (17), a second side frame (19) and a bogie longitudinal axis (34) according to claim 6, said beam stop surface functioning to contact at least one of said friction and the side frame post stop surface during operation of said chassis assembly. Said beam has an upper side and a lower side, and each of said concave regions is generally straight and approximately centrally located between said upper side of the beam (16) and the lower side of the beam (16), each said stop surface having an upper conical area extending from said beam. an upper side to said concave region and a lower conical region extending from said lower side to said convex region. A beam post stop surface for a rail vehicle chassis assembly with a beam (16), a beer side frame (17), a second side frame (19), and a chassis longitudinal axis (34) according to claim 7, wherein said generally flat region has a beer length; said upper conical region having a second length and said lower conical region having a third length and said beer length and said third length being nearly equal. A beam post stop surface for a railway vehicle chassis assembly with a beam (16), a beer side frame (17), a second side frame (19) and a bogie longitudinal axis (34) according to claim 7, wherein the generally flat beer region has a beer length. said upper conical region having a second length and said lower conical region having a third length and said beam defines a vertical length between said upper and lower sides, the first length being less than one third of the vertical length. A beam post stop surface for a railway vehicle chassis assembly with a beam, a beer side frame (17), an expensive side frame (19), and a chassis longitudinal axis (34) according to claim 9, said generally flat region having a first length, said upper conical region it has an expensive length and said lower conical region has a third length, the first length being less than any of said expensive length and said third length.