RU2454339C2 - Quasicontinuous welded track of mainline sections - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to track structure. Proposed track has two twin rails inclined toward each other instead of single rails. Rail center is rigidly secured to sleepers. Ends of said twin rails are located opposite the centers of adjacent rail and vice versa. Rail heads of every twin rails form as if edges of flute. Rails are secured to sleepers by know techniques. Opposite rails in twins are bolted together with preset spacing. Bolt ends are secured to rail center height section. Bolts should be fitted at rail ends. Bolts proper ensure stable distance between twin tails without preventing lengthwise displacements caused by thermal strains.

EFFECT: reduced impact loads, longer life, easier servicing.

2 dwg

Description

A railway track is known with two single lashes of rails, the ends of which are joined together by means of overlays and between which there are gaps of several millimeters to compensate for their temperature deformations [See "The design of the railway track and its content." Authors: M.A. Frishman, N.A. Ponomarenko, S.I. Finitsky. Moscow: Transport, 1987, pp. 34-46, 48-61, 89-95, 98-103, 167-190, 195-204, 217, 218, 247-266].

Note. The term “Quasi-continuous railroad track ...” requires clarification. The prefix “Quasi-” means “as if”, i.e. in fact, there are gaps between the ends of the rails, moreover, they can be designed for large temperature differences than is commonly expected in known devices of railway gauge with bolted joints, for example, up to 150 ° C. But, despite the presence of even increased gaps at the joints of the rails, the device of the railway track proposed by the invention almost completely eliminates their negative manifestations. More detailed information about the device and the properties of the inventive railway track are given in the description below.

Carriages (locomotives, wagons, etc.) with wheels in the form of steel disks having a ridge located on the inside of the wheel and a ski track from the outside, whose wheels rest on the rails and roll along them, move along the rails. When the wheels roll along the rails, the ridge does not allow the wheel to slide off the rail in the transverse direction, and thus the stable movement of the crews along the railway track is ensured. However, the known device of the railway track has several disadvantages:

- each section of the rail experiences a pulsating load from each wheel rolling along it, mainly bending the rail in a vertical plane, and the ends of the rails at their joints, which are consoles according to the loading scheme, experience maximum bending. And although the ends of rails adjacent in length are connected by plates that are located on both sides of the rails and are pulled together by bolts, the total rigidity of the two plates (i.e. their ability to resist bending) is several times lower than that of a solid rail. For example, for a P50 rail, it (the total stiffness of two plates) is approximately three times less than the stiffness of the rail itself. Consequently, the pads relieve the ends of the rails to a relatively small degree from increased bending and earlier break compared with the middle part of the rail. Yes, in addition, the openings on the ends of the rails, which serve to fix the pads, are stress concentrators and

often from them cracks begin, incapacitating the rail. This disadvantage is exacerbated by virtually shock load on the joints of the rails from the wheels;

- shock loads on the wheels from the joints, as a reaction to the collision of the wheels with the joint, which are transmitted to all crew elements and put them out of order prematurely;

- the rigidity of the rails in the transverse direction is insufficient, as a result of which, with random transverse loads, as well as in turns, they become curved in plan, local gauge broadening, etc., which causes wagging and swaying of cars and locomotives and, again, contributes to accelerated wear of their elements.

As for passenger trains, wheel knocks, “wagging”, swinging, etc. they do not increase the comfort of passengers.

One way to reduce the negative impact of the above factors is to reduce the number of joints: using rails twice as long (25 instead of 12.5 m), although this does not solve the problem to a more or less serious degree; the use of sections of a welded joint with a length of 500-1500 m or more, which are obtained by welding along the ends of adjacent rails.

The jointless path much more radically solves the problem of smooth movement on the rails of crews, but its application creates new problems due to its inherent disadvantages:

- the operational state of the jointless path to a large extent depends on changes in ambient temperature, especially on sudden ones, as well as on the heating of the rails by the sun.

In the jointless way, the temperature extensions of rail lashes “suppress”, fixing them to sleepers much more strongly.

But this "suppression" is not given in vain - compressive stresses appear in the cross sections of the rails with increasing temperature, which tend to lengthen the rail. But, since it cannot move along, when these stresses exceed a certain critical value (or when the temperature of the rails exceeds a critical value), the rails together with the sleepers can sharply shift in the transverse direction - the so-called “outburst” occurs, i.e. the curvature in one direction of two rail lashes simultaneously with the sleepers to a distance of 10 cm or more, which almost always leads to the descent of the rolling stock from the rails.

All of the aforementioned forces us to keep undressed sections of the track under close attention, to contain an increased contingent of workers, and to carry out all maintenance work on undressed sections especially carefully and in concert. In addition, replacing defective sections of jointless lashes is much more difficult: if at the butt sections it is enough to remove the fastening of the rails to the sleepers and between each other and replace the defective rail with a new one, then at the jointless sections it is necessary to cut the defective part of the rail, taking measures against spontaneous shift of both rail lashes in the longitudinal or transverse directions, which is time-consuming in itself, and then weld a conditioned rail to the place of the cut out section, and the welding process itself is quite complicated and has ambient temperature restrictions his air during the meeting. So, at temperatures below minus 10 ° C, such welding is generally prohibited. Yes, and the weld metal is quite inferior in strength to the metal of the whole rail and is a place of increased risk.

Proposed by the present invention, the device of the railway track eliminates the above-mentioned disadvantages of the known device of this track.

Firstly, each wheel of the crews rolls almost all the time along two rails of the double lash and only at the moment when it passes over the junction of the rails, its main bearing falls on the middle of the rail located opposite the junction in the double lash and therefore the wheel does not hit the joint going on. And in general, it is almost impossible to notice the moment the wheel passes over the junction while in the carriage.

Secondly, the load on the rails is reduced, since the mass of crews is distributed evenly over 4 rails, and not 2, which helps to increase their service life.

Thirdly, there is no need to install linings at the joints of rails and fasteners (and this is about 8 tons per kilometer of the known device of the railway gauge).

Fourthly, the rigidity of rail lashes increases: in the vertical direction twice, in the horizontal - 10 times. And as a consequence of this, as well as the fact that the opposing rails in the double lash are interconnected by tie rods, the possibility of lashes diverging from each other will greatly decrease. Those. the crews will be able to move along the railway track several times more smoothly without “wagging” and swaying, which will contribute to a significant increase in their speed.

Fifth, the working conditions of the sleepers and the railway bed as a whole will improve due to a more uniform load on them (the area of bearing of the rails on the sleepers is twice as large, which means that the specific pressure on the sleepers and the canvas is half as much).

Sixthly, it does not require laborious and troublesome maintenance, which must be performed for the trouble-free maintenance of the known jointless track, while retaining all the advantages of the railway track with "gap" joints in terms of the convenience of replacing rails.

The quasi-continuous rail gauge device is shown in FIG. 1 and FIG. 2.

Figure 1 schematically shows a top view of a portion of this track.

Here: 1 - double rail lash; 2 - tie rods with elements of their fastening to rails; A is the gap between the ends of the rails.

Figure 2 shows a cross section BB of a double lash.

Here: 3 - rail, for example, P50 12.5 or 25 m long; 4 - coupling pin with a spherical girdle "G"; 5 - a threaded sleeve with a turnkey hexagon and a "B" tapered groove; 6 - oblique washer; 7 - a nut; 8 - spring washer; D - profile of the working surface of the wheel.

The profile of the working surface of the wheel proposed by the invention consists of two parts: the left (as shown in FIG. 2), which has a known profile, starting from the side surface of the wheel to the point E of its flange farthest from the wheel axis, and symmetrical to it with respect to the axis AND of the right side .

Each rail in its middle part is fixed to the sleepers so that the possibility of moving this middle part in the longitudinal direction is excluded, and all temperature elongations (or contractions) occur due to the movement of its halves in opposite directions. In other places, rails are fastened to sleepers by known methods.

Opposite rails in double lashes are inclined towards each other at equal angles with respect to the vertical, for example, those that are adopted for single lashes in known railway gauge devices (the so-called “cradle”), while there is some space between the rails in which placed the middle part of the wheel according to claim 2 of the formula with a ridge. The heads of the rails themselves form, as it were, the edges of the trench along which this wheel rolls.

The tie rods are arranged in increments of, for example, 2 m, while they must be sure to connect the ends of the rails at the joints with the midpoints of the rails opposite in the double lashes and serve to ensure a stable distance between the rails of the double lash, while they do not interfere with the longitudinal movement of the rails at their temperature deformations, since their ends are pivotally attached to opposing rails and have the ability to rotate at a certain angle, which is determined by the magnitude of the longitudinal movement of the opposing sections rails connected by a tie rod relative to each other.

Claims (1)

A railway track having instead of two single rails two rails in which the rails are tilted towards each other at certain angles, known as the “cradle”, the middle of the rails are fixed motionless to the sleepers, characterized in that the ends of the rails of each lash in the twin are opposite the middle of the rails of a nearby whip, and vice versa, so that the rail heads of each double whip form, as it were, the edges of the gutter, and the rails are fastened to the sleepers in all places except their middle by known methods, and the opposite rails in double lashes are interconnected by pins with a pitch of, for example, 2 m, the ends of which are attached to the rails in their mid-height part, the installation of pins on the ends of the rails is mandatory, and the pins themselves are designed to ensure stable adopted in the project, the distance between the rails of the double lash, without interfering with the longitudinal movement during their temperature deformations.

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