JP7186736B2 - Rail straightening jig and rail straightening method - Google Patents

Description

The present invention relates to a rail straightening jig and a rail straightening method.

In recent years, head repair welding using thermite welding method (hereinafter, sometimes referred to as "THR welding method") has been used as a method of repairing damage (such as shelling flaws) occurring in the rail head of rails used on railway tracks. ) are attracting attention.

The THR welding method mainly consists of (a) cutting the damaged portion of the rail head by gas cutting, (b) pouring thermite molten steel into the cut portion (thermite reaction), performed by Therefore, the rail can be repaired more easily and in a shorter time than the conventional repair method.

However, in this THR welding method, the rail is repaired by injecting molten steel into the cut portion. depression) may occur. When the top surface of the rail is deformed in this manner, noise and vibration are generated when the railcar travels through the repaired area, and smooth running of the railcar may be hindered.

Therefore, Patent Literature 1 discloses a rail straightening device that performs THR welding while suppressing the occurrence of depressions in the top surface of the rail. According to the rail straightening device disclosed in Patent Document 1, in a hot state immediately after thermite welding, a hydraulic cylinder presses the head of the rail at a position separated from the repaired portion by a predetermined distance. Corrective work is performed by pulling upwards. According to the straightening work, it is possible to apply reverse strain in advance to the repaired portion of the rail head and perform vertical straightening, thereby suppressing the occurrence of depression in the repaired portion.

JP 2019-163599 A

However, according to the rail correction device disclosed in Patent Document 1, there is provided a hydraulic control device for appropriately controlling the amount of pressure (displacement amount of the rail) due to the pressure of the hydraulic cylinder, and a hydraulic control apparatus for measuring the displacement amount of the rail. displacement sensor must be provided.

When a hydraulic control device and a displacement sensor are newly provided in this way, the introduction cost of the rail straightening device increases. In addition, since the rail straightening work is generally performed outdoors, the hydraulic control device and the displacement sensor are likely to malfunction due to weather and human factors, and there are problems in the workability and reliability of the straightening work. That is, there is room for improvement in the conventional rail correction device.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a rail straightening jig and a rail straightening method that can more easily perform rail straightening work using a rail straightening device and appropriately secure the flatness of the top surface of the rail. intended to provide

To achieve the above object, the present invention provides a rail correction jig used for correcting deformation of a rail head, wherein the rail is deformed so as to curve upward when the deformation is corrected, The rail correction jig is installed in the longitudinal direction of the rail and has a body portion for supporting the rail. A sloped contact surface with the rail is formed, the slope angle of the downward slope is determined by the amount of curvature of the rail, and the longitudinal length of the body portion is determined by the curvature of the rail. It is characterized by being determined by the maximum load applied to the part.

According to the present invention, the shape of the rail correction jig, more specifically, the inclination angle determined by the amount of curvature of the rail, and the length of the main body determined by the maximum load applied to the main body, The amount of rail correction can be controlled. That is, since there is no need to provide a hydraulic control device or a displacement sensor for controlling the correction amount of the rail as in the conventional art, the introduction cost is reduced and the workability of the correction work is improved.

It should be noted that the ``curve amount of the rail'' for determining the slope angle does not refer to the ``maximum bending displacement'' of the rail when the deformation is corrected, but rather the ``to obtain the desired correction amount of the rail.'' It refers to the "necessary amount of bending".

The slope angle may be defined by the following formula (1), and the length of the main body may be defined by the following formula (2).
θ=aδ−b (1)
L=cF−d (2)
is the slope angle, .delta. is the amount of rail curvature, L is the length of the main body, F is the maximum load, and a, b, c, and d are constants.

The main body portion is arranged such that the contact surface contacts the lower surface of the rail head, and a non-contact portion is formed in the central portion in the longitudinal direction of the main body portion with which the lower surface of the rail head does not contact. , The contact surfaces may be formed on both end side portions of the non-contact portion in the longitudinal direction of the main body portion.

According to another aspect of the present invention, there is provided a rail straightening method using any one of the above rail straightening jigs, comprising the step of installing the rail straightening jig so that the contact surface is in contact with the lower surface of the rail. and a step of bending the rail upward, wherein the entire contact surface is in surface contact with the lower surface of the rail at least when the maximum load is applied to the main body.

Alternatively, in the rail correction method using the above rail correction jig, the non-contact portion corresponds to the deformed portion generated in the rail head in the longitudinal direction of the rail, and the contact surface is the rail head. installing the rail correction jig so as to be in contact with the lower surface; The entire surface is in surface contact with the lower surface of the rail head.

According to the present invention, the correction amount in the rail correction work can be controlled only by bending the rail upward after installing the main body portion of the rail correction jig on the rail. Specifically, by determining the shape (slope angle and length) of the main body according to the amount of rail curvature required for straightening and the maximum load to be applied, there is no need for a hydraulic control device or displacement sensor. A simpler rail correction work can be performed.

The method further includes a step of removing the deformed portion generated in the rail head by gas cutting, a step of supplementing the removed portion with thermite welding, and a step of hot punching and shearing the surplus thickness due to thermite welding. good.

Advantageous Effects of Invention According to the present invention, it is possible to provide a rail correction jig and a rail correction method that can more easily perform rail correction work using a rail correction device and appropriately ensure the flatness of the top surface of the rail.

It is a side view which shows the outline of a structure of a rail correction apparatus. It is an explanatory view showing the structure of a rail. It is an explanatory view showing an outline of composition of a correction jig concerning this embodiment. It is explanatory drawing which shows the example of attachment of the correction jig with respect to a rail. It is explanatory drawing which shows the mode of correction|amendment of the rail by a rail correction|amendment apparatus. It is a graph which shows the relationship between a load and bending amount. It is explanatory drawing which shows the mode of correction|amendment of the rail by a rail correction|amendment apparatus. FIG. 10 is an explanatory diagram showing another example of mounting the correcting jig to the rail; It is a graph which shows the relationship between the amount of curvatures, and an inclination angle. It is a graph which shows the relationship between the maximum load and the length of a correction jig.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification, elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

First, the configuration of a rail correction device 1 having a rail correction jig according to an embodiment of the present invention will be described. FIG. 1 is a side view showing the outline of the configuration of the rail correction device 1. FIG.

As shown in FIG. 2, the rail straightening device 1 performs the straightening operation of the rail R so that the repair portion H formed by the THR welding method on the rail head Rh is not depressed. Specifically, the repaired portion H of the rail R is preliminarily provided with reverse strain before cooling. The repaired portion H refers to a portion in which a damaged portion (for example, a shelling flaw) generated in the rail head Rh is excised by gas cutting in the THR welding method, and molten steel is injected into the excised portion. .

As shown in FIG. 1, the rail straightening device 1 includes a drive mechanism 10 for driving the rail R to bend upward when straightening the rail R, and a drive mechanism 10 for supporting the rail R while straightening the rail R and relatively upward. A correcting jig 20 that acts to lift up and a connecting member 30 that connects the driving mechanism 10 and the correcting jig 20 are provided.

The drive mechanism 10 bends the rail R upward, for example, so that the repaired portion H of the rail R is the apex. The configuration and arrangement of the drive mechanism 10 are not particularly limited. For example, the rail R may be curved by pulling it up from above, or may be curved by pushing it up from below. Further, for example, as in the rail correction device described in Patent Document 1, by pressing a predetermined position of the rail head Rh from above, the rail may be curved by the reaction of the pressing.

The drive mechanism 10 may be, for example, a cylinder or the like to mechanically bend the rail R, or may be a jack or the like to bend the rail R manually.

As shown in FIGS. 3 and 4, the correction jig 20 as a rail correction jig is formed in a substantially rectangular parallelepiped shape (for example, about L mm long and about 100 mm high) whose long side is the longitudinal direction of the rail R. It is When the rail R is corrected, the correction jig 20 has a longitudinal central portion located below the repaired portion H of the rail R, and a contact surface 21 formed on the upper surface of the rail head Rh. is placed in contact with the underside (under the chin) of the

As described above, the correction jig 20 acts to support and lift the lower surface of the rail head Rh by the contact surfaces 21, 21 when the rail R is curved by the drive mechanism 10. FIG. In other words, the correction jig 20 acts to relatively push up and bend the rail head Rh during operation of the drive mechanism 10 .

A hole portion 20a is formed in the correcting jig 20 so as to penetrate the correcting jig 20 in the thickness direction. A connection bolt 32 of a connection member 30, which will be described later, is inserted through the hole 20a.

The upper surface of the correction jig 20 is formed with the contact surface 21 with the rail R as described above. As shown in FIGS. 3(b) and 4, the contact surface 21 is formed to have a curved surface that matches the shape of the rail head Rh under the chin when the correction jig 20 is attached to the rail R. there is

On the upper surface of the correction jig 20, a notch portion 22 is formed as a non-contact portion that does not come into contact with the rail head Rh during correction of the rail R, substantially at the center of the correction jig 20 in the longitudinal direction. there is The notch portion 22 is arranged below the repair portion H of the rail R when the rail R is corrected. The notch 22 is formed with a length of about 100 mm in the longitudinal direction of the correction jig 20, for example. The correction jig 20 is arranged so that the repair portion H and the notch portion 22 are aligned in the longitudinal direction of the rail R when the rail R is corrected. Note that the cross-sectional shape of the notch portion 22 is not particularly limited as long as it is a shape that does not come into contact with the rail head Rh during correction.

Further, as shown in FIG. 3, the contact surface 21 extends from the longitudinal end of the contact surface 21 on the notch 22 side (hereinafter referred to as the "inner end 21a") toward the outer end 21b. It is formed to have a downward slope of slope angle θ.

Since the contact surface 21 is formed with a downward slope in this way, only the inner end portion 21a of the contact surface 21 can be tilted as shown in FIG. makes point contact with the lower surface of the rail head Rh. In this state, when the output of the driving mechanism 10, in other words, the load f applied to the correction jig 20 and acting relatively to bend the rail R is increased, the load f reaches a predetermined value. When it reaches, the deflection angle of the rail R coincides with the inclination angle θ of the contact surface 21, and the entire surface of the contact surface 21 comes into surface contact with the lower surface of the rail head Rh as shown in FIG. 5(b). Since the contact surface 21 and the lower surface of the rail head Rh come into surface contact with each other, the load f applied to the correction jig 20 is dispersed on the contact surface 21, and as shown in section A in FIG. The bending amount δ (see FIG. 5B) of the rail R with respect to the load f can be kept substantially constant. That is, by forming a downward slope on the contact surface 21 of the correction jig 20, it is possible to prevent the correction amount (bending amount δ) of the rail R from exceeding the required correction amount.

From the relationship between the formation of the downward slope and the amount of curvature .delta. It has been found that the amount can be better controlled. The present inventors have found that the shape (gradient angle θ and length L) of the correction jig 20 is determined by the amount of curvature δ of the rail R required to obtain the desired amount of correction of the rail R, Using the maximum output of the drive mechanism 10 for straightening, in other words, the maximum load F applied to the straightening jig 20 for straightening the rail R, it was found that the following equations (1) and (2) can be used to determine .
θ=aδ−b (1)
L=cF−d (2)
Note that a, b, c, and d in equations (1) and (2) represent constants determined by the member temperature of the rail R and material characteristic values, respectively.

It should be noted that the above formulas (1) and (2) are the gradient angle θ with respect to the amount of curvature δ of the rail obtained by the steady-state heat conduction-structural analysis model using the finite element method, and the length L with respect to the maximum load F is determined by the respective transitions of

According to the above formula (1), by increasing the inclination angle θ of the contact surface 21, the bending amount δ of the rail R can be increased. Further, according to the above formula (2), the maximum load F that can be applied to the correction jig 20 can be increased by increasing the length L of the correction jig 20 .

In the rail straightening device 1 according to the present embodiment, the straightening operation of the rail R is performed using the straightening jig 20 having the inclination angle θ and the length L determined from the above equations (1) and (2). . More specifically, when the maximum load F of the drive mechanism 10 is applied to the correction jig 20, at least the lower surface of the rail head Rh and the entire contact surface 21 are in surface contact, and the desired bending is achieved. A straightening jig 20 having an inclination angle θ and a length L that can obtain the amount δ is used to straighten the rail R.

The connecting member 30 connects the drive mechanism 10 and the correction jig 20 . The connecting member 30 has, as shown in FIG. 1, an arm 31 that connects the drive mechanism 10 and the correction jig 20, and a connection bolt 32 that is inserted through the hole 20a of the correction jig 20. .

The rail correction device 1 according to this embodiment is configured as described above.

According to the rail straightening device 1 according to the present embodiment, from the above equations (1) and (2), the maximum load F by the drive mechanism 10 used for straightening the rail R and the required bending amount δ of the rail R are Accordingly, the shape of the correction jig 20 can be calculated. By correcting the rail R using the correction jig 20 having the calculated shape, it is appropriately suppressed that the rail R is curved (corrected) in excess of the required amount of correction. In other words, since the correction amount of the rail R can be controlled only by the shape of the correction jig 20, there is no need to provide the rail correction device 1 with a displacement sensor or a hydraulic control device unlike the conventional rail correction device 1, and the rail correction device 1 can be introduced. The cost can be appropriately reduced, and the workability of correction work can be appropriately improved.

Next, a method of repairing the rail R using the THR welding method and a method of correcting the rail using the rail correction device 1 configured as described above will be described.

First, the damaged portion of the rail head Rh is repaired by the THR welding method. In the THR welding method, the damaged portion of the rail head Rh is excised by gas cutting, the cut surface is ground by a grinder, and then a penetrant inspection is performed to check for residual deformation (cracks, etc.).

Next, a mold is placed at the cut portion, and after preheating with an oxygen/propane flame, thermite molten steel is poured into the mold, and after the molten steel has solidified, the excess metal is punched out. The portion of the rail head Rh that has been cut and injected with molten steel is the repair portion H in this embodiment.

After the molten thermite steel is punched out and sheared, the rail R is straightened by the rail straightening device 1 while the temperature of the repaired portion H is high due to the injection of the molten thermite steel.

In the correction work of the rail R, first, the correction jig 20 is installed on the rail R. As shown in FIG. When installing the correction jig 20, the correction jig 20 is placed on the web of the rail R so that the longitudinal central portion of the correction jig 20, that is, the notch portion 22 is positioned below the repair portion H in a side view. Arrange along the part. At this time, since the contact surface 21 of the correction jig 20 has a downward slope, as shown in FIG. Only the ends 21a are in contact.

After the correcting jig 20 is installed, the driving mechanism 10 bends the rail R into an arcuate shape with the repaired portion H at the apex. At this time, the correcting jig 20 functions as an action point that lifts the lower surface of the rail head Rh upward and gives a reverse strain to the periphery of the repaired portion H. As shown in FIG.

Here, when the output of the driving mechanism 10 is increased when the rail R is curved, when the load f applied to the correction jig 20 reaches a predetermined value, the deflection angle of the rail R and the inclination angle θ of the contact surface 21 are coincide with each other, and the lower surface of the rail head Rh and the contact surface 21 come into surface contact as shown in FIG. 5(b). In the straightening operation of the rail R, it is necessary to straighten the rail R by a predetermined bending amount δ. As shown in section A of , the amount of curvature σ can be kept substantially constant. That is, the bending amount δ of the rail R can be appropriately controlled, and the correction work of the rail R can be performed more appropriately.

Further, here, when the output of the drive mechanism 10 further increases and the load f applied to the correction jig 20 exceeds a predetermined value, the bending amount .delta. There is a risk that the ability to maintain the constant will be impaired. This is because the surface contact between the lower surface of the rail head Rh and the contact surface 21 is released due to the increase in the load f, and as shown in FIG. It is thought that it is caused by coming into contact with each other.

However, according to the method for correcting the rail R according to the present embodiment, when correcting the rail R, the amount of bending δ of the rail R required for correction and the maximum load F by the driving mechanism 10 used for correcting the rail R , is used. That is, when the maximum load F is applied by the driving mechanism 10, the entire contact surface 21 is in surface contact with the lower surface of the rail head Rh. 6 and FIG. 7, the excess bending amount δ of the rail R is appropriately suppressed.

In this way, the rail R is corrected with an appropriate amount of curvature δ, and thus the reverse strain can be appropriately applied to the periphery of the repaired portion H, so that the rail R after repair is appropriately prevented from being depressed. Suppressed.

Further, in this embodiment, the correction jig 20 is installed on the rail R so that the notch 22 formed in the central portion in the longitudinal direction is positioned corresponding to the repaired portion H. As shown in FIG.

As described above, the temperature around the repaired portion H after the hot punching shearing is performed is higher than the transformation point (for example, about 700° C.) of the rail R, so that the peripheral portion of the repaired portion H is It is easily deformed. Therefore, when the lower surface of the rail head Rh and the correction jig 20 come into contact with each other in the vicinity of the repaired portion H, the contact portion is locally deformed. There is a risk that it will become and remain.

On the other hand, according to the present embodiment, since the notch 22 corresponds to the repaired portion H as described above, the lower surface of the rail head Rh is supported while avoiding the vicinity of the repaired portion H, which has become hot. can be done. As a result, local deformation at the contact portion between the rail head Rh and the correction jig 20 is appropriately suppressed.

When the correction work of the rail R is completed, next, forced air cooling for adjusting the hardness of the top surface of the rail R is performed. This cooling may be natural cooling, but in order to appropriately increase the height of the top surface of the rail R, it is desirable to use forced air cooling by injection of compressed air or the like. After the rail R is air-cooled, the shape of the rail R to be repaired is prepared by a grinder, and the repair of the rail head Rh by the THR welding method and the correction of the rail R by the correction jig 20 are completed. After completion of the THR welding method, the presence or absence of repair welding defects may be confirmed by ultrasonic inspection, for example.

According to the rail straightening method according to the present embodiment, the shape (gradient angle θ, By using the correction jig 20 having the length L), the correction work of the rail R can be performed appropriately. Specifically, since it is suppressed that the rail R is bent in excess of the required amount of correction, it is possible to appropriately apply a reverse strain to the repaired portion H of the rail R, so that the repaired portion H can be corrected. It is possible to appropriately suppress the occurrence of sagging in the rail R.

Further, according to the rail straightening method according to the present embodiment, by arranging the notch 22 below the repaired portion H, local deformation does not occur at the contact portion between the straightening jig 20 and the rail head Rh. can be appropriately suppressed.

In the above embodiment, the correcting jig 20 is arranged along the web portion of the rail R to support the rail head Rh from below. is not limited to this.

For example, as shown in FIG. 8, the correction jig 20 may be arranged on the lower surface of the rail bottom portion Rb. In such a case, the correcting jig 20 may be used, for example, after excavating and removing the installation surface of the rail R (for example, ballast or sleeper), and then inserting the correcting jig 20 into the excavated or removed portion, for example, through the hole 20a. It can be installed by extending the connecting bolt 32 under the R.

When the correction jig 20 is arranged on the lower surface of the rail bottom Rb in this way, the rail bottom Rb is less affected by the ambient temperature of the repaired portion H. Since it is lower than the point, local deformation does not occur at the contact point with the correction jig 20 . That is, when the correction jig 20 is arranged on the lower surface of the rail bottom portion Rb, the notch portion 22 may not be formed on the upper surface of the correction jig 20 as shown in FIG.

Although the preferred embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to such examples. It is obvious that a person skilled in the art can conceive various modifications or modifications within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. accepted as a thing.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.

In this embodiment, a correction jig 20 having a predetermined shape is installed on the rail R having the repaired portion H on the rail head Rh, and a hydraulic cylinder is used as the drive mechanism 10 to apply a predetermined hydraulic pressure to the rail R. After performing the straightening work, the finishing work (finish grinding with a grinder) is performed, and the amount of displacement of the cylinder shaft (mm), the finished shape of the top surface of the rail R after the finishing work (mm), the amount of curvature of the rail R δ ( mm) was measured.

Then, using the obtained measurement results, a relational expression between the amount of curvature δ and the slope angle θ of the rail R, and a relational expression between the maximum load F and the length L of the hydraulic cylinder were calculated using the finite element method. It was obtained by a conduction-structure analysis model.

9 and 10 show the relationship between the amount of curvature δ and the slope angle θ and the relationship between the maximum load F and the length L, respectively, obtained under the above conditions.

As shown in FIG. 9, the above analysis revealed that the amount of curvature δ and the slope angle θ have a linear relationship represented by the above equation (1). Here, when the rail R having the repair portion H on the rail head Rh is targeted as in this embodiment, the constants a and b shown in the above formula (1) are a=0.1242 and b=0, respectively. .1087.

As shown in FIG. 10, the above analysis revealed that the maximum load F and the length L have a linear relationship represented by the above equation (2). Here, when the rail R having the repair portion H on the rail head Rh is targeted as in this embodiment, the constants c and d shown in the above formula (2) are c=1.6417 and d=358, respectively. 0.49.

As can be seen from the above results, for example, when obtaining a bending amount δ of 10 mm using a hydraulic cylinder with a maximum load F of 450 kN, θ = 1.13° from the above equations (1) and (2). , L=380 mm. In other words, using the straightening jig 20 having a shape of θ=1.13° and L=380 mm, the rail R is straightened with the maximum load F (450 kN) of the hydraulic cylinder. 10 mm, which is the required amount of curvature δ of the rail R, can be obtained.

INDUSTRIAL APPLICABILITY The present invention is useful when correcting a rail after repair by the THR welding method.

Reference Signs List 1 rail straightening device 10 drive mechanism 20 straightening jig 20a hole 21 contact surface 22 notch 30 connecting member f load F maximum load H repair part L length (of straightening jig) R rail Rh rail head Rb rail bottom δ Amount of curvature

Claims (6)

A rail correction jig used to correct deformation occurring in a rail head,
the rail is deformed so as to curve upward when correcting the deformation;
The rail correction jig is
Having a body portion installed in the longitudinal direction of the rail and supporting the rail,
A contact surface with the rail is formed on the upper surface of the main body portion, and has a downward slope from the central portion toward the end portions in the longitudinal direction of the main body portion,
The slope angle of the downward slope is determined by the amount of curvature of the rail,
A jig for correcting a rail, wherein a longitudinal length of the main body is determined by a maximum load applied to the main body by bending of the rail. The slope angle is defined by the following formula (1),
The rail correction jig according to claim 1, wherein the length of the main body is defined by the following formula (2).
θ=aδ−b (1)
L=cF−d (2)
here,
θ: Gradient angle δ: Rail curvature amount L: Body length F: Maximum load a, b, c, d: Constant The main body portion is arranged such that the contact surface is in contact with the lower surface of the rail head,
A non-contact portion that does not come into contact with the lower surface of the rail head is formed in the central portion in the longitudinal direction of the main body,
3. The rail correction jig according to claim 1, wherein the contact surfaces are formed on both end side portions of the non-contact portion in the longitudinal direction of the body portion. A rail correction method using the rail correction jig according to any one of claims 1 to 3,
installing the rail correction jig so that the contact surface is in contact with the lower surface of the rail;
bending the rails upward;
A rail straightening method, wherein the entire contact surface is in surface contact with the lower surface of the rail at least when the maximum load is applied to the main body. A rail correction method using the rail correction jig according to claim 3,
installing the rail correction jig so that the non-contact portion corresponds to the deformed portion of the rail head in the longitudinal direction of the rail, and the contact surface is in contact with the lower surface of the rail head;
bending the rails upward;
The rail straightening method, wherein the entire contact surface is in surface contact with the lower surface of the rail head at least when the maximum load is applied to the main body. a step of removing the deformed portion generated in the rail head by gas cutting;
a step of supplementing the excised portion with thermite welding;
6. The rail straightening method according to claim 4 or 5, further comprising the step of hot-punching and shearing excess thickness from thermite welding.

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