SU1735473A1 - Method of reducing rated stressed of jointless rail track - Google Patents

Abstract

The invention relates to railway transport, and more specifically to the field of the current maintenance of a continuous rail track. The aim of the invention is to simplify the process of restoring the design tension of a rail rail of a continuous rail and improving the quality of work. After identifying the section of the rail lash of the continuous track with actual stress deviations from the calculated values, for example, between control sections 2-6, in this area the rail lash is released from communication with the base and, starting from control section 2, the rail lash is bent, for example, in a vertical plane, and then the resulting wave is moved to control section 6. In this area, the compressive stress in it is reduced. Up to control cross-section 4, the bending arrow is increased by an amount proportional to the actual deviation of the stretch from the calculated values. Beginning from control section 4 to section 6, the bending arrow is also reduced by an amount proportional to the actual deviation from the calculated values. 3 il. sl C

Description

The invention relates to railway transport, in particular to the operation of a railway track.

The purpose of the invention is to simplify the process of restoring the calculated stress state of the rail scourge of the continuous rail and improving the quality of work production.

FIG. Figure 1 shows the stress diagram in a rail whip arising from its operation; in fig. 2 is a diagram of the arrows of the bend of a rail scourge on its individual sections, where deviations of actual stresses from calculated values are detected; FIG. 3 is a plot of design stresses.

The method is carried out as follows.

The rails welded in the rod by the electrocontact method are fixed to a constant mode of operation, for example, at 20 ° C (Tccr 20 ° C). The whip is laid and operated in the forward area. During operation, the rail scourge of the continuous path monitors its tense state, for example, by moving the control sections 1-8 relative to fixed frames. The distance between the benchmarks can be selected with a certain step, for example, 25 m. When monitoring the stress condition of the rail scourge, section 3 was found to move towards section 2 by 2 mm, section 4 moved towards section 3 by 6 mm , section 5 has moved in the direction of the sevi co w eat vi

4 by 2 mm while maintaining the position of the remaining sections. The temperature of the rails at this time was, for example, 30 ° C (tp 30 ° C).

Consequently, in the section of the rail scourge of the continuous track between the control sections 2-6, the actual stresses differ from the calculated values, and the actual stresses between the control sections 2-4 are smaller than the calculated values, and between the control sections 4-6, more than the calculated values .

The calculated stress value is determined by the formula

, 5 Atx-25 MPa,

where At is the difference between the fastening temperature of the scourge and the actual temperature of the rails (At.zakr - Atp).

The change in the temperature of the fastening of the rail scourge in the areas between the control sections 2 and 3, Zi4. 4 and 5, 5 and 6 is determined by the formula l - ± D

DT.izm - -Ј-G {7,

where AI is the amount of movement of the control section in the direction of decreasing (-) or increasing (+) the distance between the sections, mm;

a is the linear expansion coefficient of rail steel, and 0.0000118 1 / degree;

L is the length of the section of the lash between the control sections, mm.

LChzm2 3 u. -7 ° C: Agism 3 4 -14 ° C; Logism is 14 ° C; Ahizm5 6 7 ° C.

The magnitude of the difference between the actual value of the stresses and its calculated values is determined by the formula

SG ,, 5-Lt.iz.

Cl | 2 3 -17.5 MPa; -35 MPa; 35 MPa; 17 MPa.

Thus, between the control sections 2 and 3, the average value of the actual stresses will be less than the calculated values and equal O2-3.4.5 MPa, in the area between the control sections 3 and 4, the average value of the actual voltages will be less than the calculated values and equal to MPa, in the area between the control sections 4 and 5, the average value of the actual stresses will be more than the calculated values and equal to 04-5 10 MPa, in the area between the control sections 5 and 6, the average value of the actual voltages will be more than the calculated values and equal to O5- 6-7.5 MPa.

After identifying the section of the rail scourge of the continuous track with actual deviations of stresses from the calculated values (in this case between control sections 2-6), this section frees the rail band from communications with the base and, starting from control section 2, the rail whip is bent, for example, in a vertical plane, and then the wave is transferred to the control section 6. As the curved portion of the rail band becomes slightly longer, the compressive stresses in it are reduced in this area. Depending on the length of the curved section and the bending boom, the compressive stresses in the rail are reduced to a calculated value. In the process of moving the formed wave to the control section 4, its bending boom is increased by an amount proportional to the actual deviation of the stresses from the calculated

0 values of individual sections of the rail. Starting from the control section 4 and to the control section 6 when the wave moves, its bending boom is reduced in the process of moving by an amount proportional to the actual deviation from the calculated values of individual rail sections. As the boom decreases, the curved portion becomes somewhat shorter and compressive stresses appear in this area.

0 In this example, depending on the length of the curved section and the magnitude of the decrease in the bending boom, the compressive stresses in the rail increase to the calculated values (Fig. 2). After restoring the calculated stress state of the rail scourge of the continuous joint, the freed part of it is fixed on the rail base (Fig. 3).

Claims (1)

Invention Formula 0 A method of restoring the calculated stress state of a rail scourge of a continuous joint, which consists in revealing a portion of the rail scourge with actual deviations of its stress state from the calculated values for a given rail temperature, stresses more and less than the calculated values, release the rails of this section from communication with the base, bend the detached rail lash, continuously move the bending boom, increase it during movement by an amount proportional to ionalnuyu actual deflection voltages 5 from the calculated values and individual sections of the rail with stresses less than the calculated values and fix the released section of the rail on the rail base, characterized in that, in order to simplify the process of restoring the calculated stress state of the rail runway of the continuous butt and improve the quality of work, reduce the bending arrow during its movement over the zone with actual stresses greater than the calculated values.