JP4914531B2 - Rail tension gas pressure welding method - Google Patents

Description

  The present invention relates to a method of cutting a defective rail generated in a non-moving section of a long rail and replacing it with a new rail. More specifically, a part of a long rail laid at a medium temperature is cut in winter and a new rail The present invention relates to a method for joining a cut portion of a long rail and a replacement rail when it is necessary to replace the rail.

When laying long rails, the axial force, which is the internal pressure of the rails, is minimized by laying the rails at the intermediate temperature, which is a climate between summer and winter, taking into account the expansion and contraction of the rails accompanying changes in temperature. I have to.
The long rail has a movable section on both sides that expands and contracts, and a fixed section that does not expand and contract because the resistance force of the fastening device such as a concrete sleeper is higher than the force that the rails extend or contract. In this immovable section, an internal pressure that tends to shrink in winter and a rail axial force that tends to increase in summer are generated.
When a crack or the like occurs in the immovable section of a long rail laid at a medium temperature, if this defective portion is cut in winter, the axial force of the rail becomes zero and the rail cutting portion opens greatly. Therefore, when connecting a new rail, it was necessary to apply pressure to the new rail so that the original rail axial force was applied.

Conventionally, when exchanging rails in winter, as shown in FIGS. 11A and 11B, the rail 2 including the defective portion 1 is cut and removed at the central positions A and B between sleepers.
Next, a predetermined pressure is applied to the rails R1 and R2 outside the cut portion by a rail tensioner which is a machine for pulling the rails, and then a rail 3 slightly shorter than the rail 2 is inserted into the place where the rail 2 is located. Conventionally, there is a joining method in which the metal 4 is melted and connected to the gap between the cutting positions A and B and the rails R1 and R2.

Further, as shown in Patent Document 1, one end of a rail 3 having the same length as the rail 2 is joined to one of the cut portions of the long rail, and the other end of the rail 3 is connected to a predetermined rail axial force (planned axial force). After the other end of the rail 3 comes into contact with the other of the cut portions of the long rail, a pressure obtained by adding a rail pressure is added to the pressure to be tensioned. And heating the cut part of the long rail to perform rail pressure welding. When the tension reaches the rail axial force (planned axial force), the connection part is stopped and the rail pressure welding is performed. A method of fastening the rail is proposed.
JP 36-36355

  However, in the former former method, the weld metal different from the rail is melted and joined between the rails so that different metals are in contact with each other, the weldability is poor, and the fatigue strength of the joint portion is low. There was a problem.

In addition, the method described in Patent Document 1 is a method in which heating of the connecting portion is stopped and the rail is pressed when the tension reaches the rail axial force. In order to remove the pressure contact, the axial force of the rail 3 in the tensioner becomes 0 tonf.
Therefore, when the tensioner is disassembled and removed from the rail, the axial force 0 tonf of the rail 3 and the axial forces of the rails R1 and R2 tensioned outside the tensioner cancel each other, and the axial force near the rail 3 is Phenomenon that it becomes lower than the planned axial force set in.

A specific example will be described using the axial force distribution diagram of the long rail in FIG.
In FIG. 12, the vertical axis represents the axial force, the horizontal axis represents the length, the underline represents the axial force of 0 tonf, and the axial force area represents the axial force × length. Note that the rails on both sides in the figure are not connected. When the axial force 150 and the movable section 151 are set, the movable section 151 is a section in which the rail is movable, and is a value obtained by dividing the axial force 150 by the resistance force γ (also referred to as a roadbed longitudinal resistance force). The immovable section 152 is a section in which the rail does not move at all (FIG. 12A).

  Here, when a rail flaw A occurs in an intermediate portion of the immovable section 152 and the rail including the rail flaw A is replaced with the rail 156, first, when the vicinity of the rail flaw A is cut, an axial force 150 is applied to the immovable section 152. Therefore, a rail corresponding to the size is opened, and a movable section 151 is formed on both sides of the cut end face (FIG. 12B).

Next, the rail including the rail flaw A is removed, and a new rail 156 is inserted. At this time, since the gas pressure welding is performed at the joint 159, the rail fastening in the range of the rail 158 is disassembled so that the gas pressure welding machine can be attached, and the rail in the range of the rail 157 is attached at the joint 162 to attach the tensioner. Dismantle the conclusion. As a result, the axial force in the section of the rails 157 to 158 becomes 0 tonf.
And it joins by performing normal gas pressure welding in the junction part 159 (FIG.12 (c)).

Next, a tensioner is attached to the existing rail position 160 and the position 161 of the new rail 156, and a pressure welding machine is attached to the inside thereof. Then, gradually increase the axial force with the tensioner, and when the rail end on the existing rail position 160 side and the new rail end 156 come into contact with each other, press contact pressure (γ + β) is added to the axial force with a gas pressure welding machine. The joint 162 is heated, and the joint 162 is subjected to gas pressure welding. When the axial force of the tensioner reaches a value obtained by adding a predetermined planned axial force 150 + pressure welding pressure calculated from the outside air temperature, the heating is stopped and the joint 162 is stopped. The gas pressure welding is finished, the pressure pressure (γ + β) is removed from the axial force of the tensioner, and only the planned axial force 150 is left. At this time, the axial force of the rail 163 inside the tensioner becomes 0 tonf (FIG. 12E).
After that, the rail fastening in the outer sections B to D and E to G of the tensioner whose axial force has changed during gas pressure welding is once disassembled, and the axial force between them is equalized by hitting the rail with a wooden hammer or the like. The fastening axial force equalization process is performed. Then, after the gas pressure contact part 162 falls to 300 ° C., the tensioner is disassembled.

When the tensioner is disassembled, the rails in the sections C to D and E to F corresponding to the stationary section length 151 from the end of the tensioner are affected by the tensioner inner rail 163 having no axial force.
That is, the planned axial force 150 between the sections C to D and E to F and the 0 tonf axial force between the sections D to E are averaged between the sections C to F. As a result, the axial force between the sections C to F is averaged. There was a problem that the shortage 168 remained.
Insufficient axial force may cause rail overhang when the rail temperature rises in summer, which is not preferable for long rail maintenance.
Note that the sections B to C and F to G are not affected by the movement section length 151 because they are farther than the movable section length 151.

In order to eliminate this axial force deficiency 168, the rail end surface 153 at the time of rail cutting shown in FIG. 12B is used instead of the predetermined planned axial force 150 calculated from the outside air temperature in the tensioner after the end of gas pressure welding. Currently, there is a method of calculating an axial force generated when 154 and 154 coincide with each other and using it as a holding axial force. This will be specifically described from the axial force distribution diagram of the long rail of FIG.
FIG. 13A shows a state where the gas pressure welding of the joint 162 has been completed. Since the axial force generated when the rail end faces 153 and 154 coincide with each other at the time of rail cutting is held in the tensioner, the axial force area 164 for setting the rail 163 inside the tensioner to the axial force 150 is from section B to It corresponds to the axial force areas 168, 169, 170, and 171 of D and E to G.
The magnitude of the axial force 172 of the axial force areas 168, 169, 170, 171 is obtained by dividing the value obtained by multiplying the length 163 in the tensioner by the axial force 150 by the total length of the sections BD and EG. Is calculated. That is, the axial force 173 of the tensioner after completion of the gas pressure welding is larger than the axial force 150 by the axial force 172 (FIG. 13A).

Further, the rail movable section 175 generated when the tensioner is disassembled is a value obtained by dividing the axial force 173 by the resistance force γ (also referred to as a roadbed longitudinal resistance force), and thus is longer than the movable section 151 ((( b)).
When the tensioner is disassembled, the rail axial forces in the sections C ″ to D and E to F ″ corresponding to the fixed section length 175 from the end of the tensioner and the axial force 0 tonf between the sections D to E are averaged. However, since the sections B to C ′ and F ′ to G are far from the immovable section length 175, they are not affected, so the axial force 173 remains.
That is, there is a problem that the axial force area 181 is insufficient in the sections D to E, and the axial force 173 higher than the predetermined axial force 150 remains in the sections B to C ′ and F ′ to G (FIG. 13C). . Insufficient axial force for only a part of the long rail may cause rail overhang when the rail temperature rises in summer, which is not preferable for maintenance of the long rail. Further, if the axial force increases only in a part of the long rail, the rail opening amount when the rail of that part breaks becomes larger than the maintenance reference value, which is also not preferable for the maintenance of the long rail.
For this reason, after the tension gas pressure welding, the rail outside the tensioner is subjected to axial force equalization processing for a predetermined length, and then the tensioner is disassembled and then the long rail that has been tensioned is disassembled. There has been a demand for a method that minimizes the increase in axial force even when there is no shortage of axial force and there is a section in which the axial force increases.

  Moreover, in the construction method described in Patent Document 1, in order to give a predetermined axial force and a planned axial force by the tensioner, the tensioner pressure when the other end of the replacement rail comes into contact with the other of the cut portions of the long rail. When the contact pressure is applied to the burner and the abutment is heated while increasing the pressure of the tensioner, the rail contact is higher than the predetermined pressure when the temperature does not rise sufficiently due to the pressure increase. In some cases, pressure was applied. If it becomes like this, since the contact part will be crushed when the temperature of the rail abutting surface of an contact part does not reach sufficient joining possible temperature, it was easy to produce the joining defect.

  In addition, in the conventional method and the method of Patent Document 1, in anticipation of the axial force of the rail in the tensioner becoming 0 tonf after the rail pressure welding, the corresponding pressure is applied to the rails before and after the tensioner with the tensioner. Because a force larger than the original axial force acts on the rail before and after the tensioner, it is necessary to disassemble the sleeper that fastens the rail long before the tensioner is attached so that it is not pulled by the tensioner. It was.

Further, after the end of the pressure welding, a rail fastening device corresponding to the length obtained by dividing the set axial force by the roadbed vertical resistance value (generally 0.6 to 1.0 tonf depending on the track structure) from both ends of the rail fastening and dismantling location. Once disassembled, an axial force equalization process is performed in which the rail axial force outside the tensioner is evenly distributed and re-fastened over the entire length of the rail.
The rail length for this axial force equalization process increases in proportion to the magnitude of the axial force set by the tensioner. Therefore, in anticipation of the axial force of the rail in the tensioner becoming 0 tonf, When this pressure is applied to the rails R1 and R2 before and after the tensioner, there is a problem that the work time and work amount of the axial force equalization process increase.

  The present invention has been made in view of the above circumstances, and when exchanging a rail where a defective portion has occurred at a medium temperature or lower, a predetermined axial force is uniformly applied to the rail to be replaced and the rails before and after the rail. To provide a rail tension gas pressure welding method that simplifies the work time and the amount of work, eliminates the need to change the rail setting even in the summer when the rail expands, and increases the reliability of the joint. With the goal.

In order to achieve the above object, the rail tension gas pressure welding method according to claim 1 is characterized by including the following steps in a method of cutting a defective rail generated in a long rail immovable section and replacing it with a new rail. Yes.
First, the axial force generated when the rail end surfaces of the cut rails are matched with each other is calculated as a holding axial force.
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails The first step of applying the tension to perform (a portion of FIG. 1).
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a constant pressure (γ) is applied to the rail located inside the rail tensioner by the gas pressure welding machine and tension is applied. For rails located outside the vessel, the rail pressure (β) is obtained by subtracting the pressure (γ) already applied to the rail located on the inside from the gas pressure, in addition to the tension at the time of contact. The second step (b) in FIG. 1 is performed by heating the contact portion between the rails and applying the rail pressure welding while applying a certain pressure tension between the rails.
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. (Part C in FIG. 1).
When the pressing tension force reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a rail pressing force (β), heating of the contact portion is stopped to complete the rail pressing, and the pressing tension The pressure (β) applied at the time of contact is removed from the force, and only the pressure obtained by adding the desired pressure to the holding axial force is applied to the rail located outside the tensioner, and the rail located inside the rail tensioner In contrast, the pressure (γ) is continuously applied to the rail of a predetermined length outside the tensioner by continuously applying the pressure (γ) by a gas pressure welding machine (part 2 in FIG. 1).
A fifth step of disassembling the tensioner and the gas pressure welding machine between the rails after the gas pressure welding portion by the rail pressure welding has become 300 ° C. or less so that the holding axial force is generated in the rail;

The rail tension gas pressure welding method according to claim 2 is characterized in that it includes the following steps in a method of cutting a defective rail generated in the long rail immovable section and replacing it with a new rail.
First, the axial force generated when the rail end surfaces of the cut rails are matched with each other is calculated as a holding axial force.
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails The first step of applying tension to perform (a portion of FIG. 6).
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a certain pressure (γ) is added to the rail located outside the tensioner in addition to the tension force at the time of contact. A second step of performing rail pressure welding by heating the contact portion between the rails while applying the gas pressure welding pressure (β + γ) as a constant pressure tension between the rails.
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. (Part C in FIG. 6).
When the pressing tension reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a gas pressure (β + γ), heating of the contact portion is stopped to complete rail pressure welding, and the pressure tension The pressure (β + γ) applied at the time of contact is removed from the force, and only the pressure obtained by adding the desired pressure to the holding axial force is applied to the rail located outside the tensioner, and the rail located inside the rail tensioner A fourth step of performing axial force equalization processing on the rail of a predetermined length outside the tensioner by applying a pressure equal to the pressure (γ) to the pressure (γ).
A fifth step of disassembling the tensioner and the gas pressure welding machine between the rails after the gas pressure welding part by the rail pressure welding has become 300 ° C. or less so that the holding axial force is generated in the rail.

The rail tension gas pressure welding method according to claim 3 is characterized by including the following steps in a method of cutting a defective rail generated in the long rail immovable section and replacing it with a new rail.
First, while calculating the axial force generated when the rail end surfaces of the cut rails are matched with each other as a holding axial force,
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails The first step of applying tension to perform (a portion of FIG. 7).
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a certain pressure (γ) is added to the rail located outside the tensioner in addition to the tension force at the time of contact. A second step of performing rail pressure welding by heating the contact portion between the rails while applying the gas pressure pressure (β + γ) as a constant pressure tension between the rails (FIG. 7B).
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. (Part C in FIG. 7).
When the pressing tension reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a gas pressure (β + γ), heating of the contact portion is stopped to complete rail pressure welding, and the pressure tension The pressure (β + γ) applied at the time of contact is removed from the force, and a pressure obtained by adding the balanced axial force α to the pressure obtained by adding the desired pressure to the holding axial force to the rail located outside the tensioner is applied. Then, the 4th process (D part of FIG. 7) which performs an axial force equalization process to the rail of predetermined length outside a tensioner.
After the gas pressure contact portion due to the rail pressure contact becomes 300 ° C. or less, the application of the balanced axial force α by the tensioner is stopped, the construction of the tensioner and the gas pressure welder between the rails is disassembled, and the holding axial force is 5th process made to occur in.

  According to a fourth aspect of the present invention, in the rail tension gas pressure welding method according to the first to third aspects, when the rail contact portion is heated to perform the rail pressure contact in the third step, a constant pressure contact pressure is always applied to the contact portion. The press tension force is controlled so as to occur.

A fifth aspect of the present invention is the rail tension gas pressure welding method according to the first to third aspects, wherein the holding axial force is determined when the rail end surfaces of the cut rails are matched with each other in consideration of rail laying conditions. It is characterized by being calculated as a value different from the axial force.
This value has both a case where the value is larger than the axial force generated when the rail end faces are matched and a case where the value is small.

According to the construction method of claim 1, when gas pressure welding is performed by a gas pressure welding machine after the rails come into contact with each other, a constant pressure (γ) is applied to the rail located inside the rail tensioner. The pressure applied to the rail already located on the inner side from the gas pressure contact pressure by adding to the tension force at the time of contact with the rail located outside the tensioner while being given by the gas pressure welding machine (γ) The rail contact surface between the rails is heated by applying a constant pressure tension force between the rails while applying a certain pressure contact tension (β) minus the rail. The contact portion can be crushed at a time when the temperature reaches a sufficient bondable temperature, and the bonding quality can be improved.
Moreover, while giving only the pressure which added desired pressure to holding axial force (axial force produced when the rail end surfaces of the cut | disconnected rails are matched) with respect to the tensioner outer rail after completion | finish of gas pressure welding, By continuously applying the pressure (γ) to the rail located inside the rail tensioner by the gas pressure welding machine, the axial force equalization process is performed on the rail of a predetermined length outside the tensioner, thereby allowing the gas pressure welding. Even when the tensioner and the gas pressure welding machine are disassembled after the temperature of the section becomes 300 ° C. or less, even if the long rail including the gas pressure welding part does not have insufficient axial force and a section where the axial force is partially increased occurs. The axial force can be increased by 10% or less.
Therefore, a force larger than the planned axial force does not act on the rails before and after the tensioner, and it is possible to prevent the sleeper that fastens the rail from being unnecessarily lengthened before attaching the tensioner. .

According to the construction method of the second aspect, the pressure (γ) and the rail pressure contact force (β) are added to the tension force of the tensioner and pressed, thereby heating the contact portion between the rails and performing the rail pressure contact. The contact portion can be crushed at the time when the temperature of the rail abutting surface of the contact portion has reached a sufficient bondable temperature, and the joining quality can be improved.
And, at the end of the pressure welding, by applying a pressure equal to the pressure (γ) to the rail located inside the rail tensioner by the pressure applying means, the gas pressure welding portion is made similar to the construction method of claim 1. Insufficient axial force does not occur in the long rails included.

According to the method of claim 3, as in the method of claim 2, the pressure (γ) and the rail pressure contact force (β) are applied in addition to the tension force of the tensioner, so that the contact portion between the rails Since the rail is welded by heating the contact portion, the contact portion can be crushed when the temperature of the rail abutting surface of the contact portion reaches a sufficient bondable temperature, and the joining quality can be improved.
Then, at the end of the press contact, the rail located outside the tensioner is given a pressure obtained by newly adding the balanced axial force α to the pressure obtained by adding a desired pressure to the holding axial force. Similar to method 2 above, there is no shortage of axial force in the long rail including the gas pressure contact portion.

  According to the method of claim 4, when the rail contact portion is heated to perform the rail pressure contact (third step), the contact portion is always joined with a constant pressure contact pressure, so the quality of the pressure contact portion is increased. Improvements can be made.

  According to the construction method of claim 5, when the axial force calculated from the opening when the rail is cut is lower or higher than the maintenance management axial force, the calculated holding axial force is increased or decreased to generate tension gas. After pressure welding, axial force equalization processing and tensioner disassembly can be used as maintenance axial force for maintenance.

A rail tension gas pressure welding method as a first example (corresponding to claim 1) of an embodiment of the present invention will be described with reference to the drawings.
First, as shown in FIG. 10, the rail R3 including the defective portion 1 is cut at the cut portions A and B. When the rail is cut, the axial pressure becomes 0 tonf, so the rail shrinks. When the amount of reduction at this time is less than the compression amount necessary for pressure welding described later, the fastening devices before and after the rails R1 and R2 are loosened, the rail is contracted, and the compression amount necessary for pressure welding is ensured.

  The cutting rail is removed, the replacement rail R4 that is longer than the cutting portion (between AB) is installed in the cutting portion, and one end is joined to the cutting portion B. The cut portion B is joined by a normal gas pressure welding. A pressure welding method using a gas pressure welding machine will be described later.

Next, the other end of the exchange rail R4 to which the cutting point B is joined is placed along the laying rail R1 and cut so that there is a gap between the cutting point A in anticipation of expansion in the summer.
After the replacement rail R4 is cut, end face processing is performed so that the cut point A and the end of the replacement rail R4 face each other, and the rail tensioner C is attached between the rail R1 and the replacement rail R4 as shown in FIG. To do.

That is, one side of the rail R1 is fixed with the first fixture 11 as shown in FIG. The fixture 11 is semicircular, and a close contact portion 12 to the rail R1 provided with a tooth-shaped groove is formed in the diameter portion thereof, thereby securing the rail R1. An L-shaped first arm portion 14 is pivotally attached to the curved surface 13 of the first fixture 11 so as to be rotatable. The pivot attachment of the first fixture 11 and the first arm portion 14 forms a curved groove 15 having the same radius of curvature as the curved surface 13 at the tip of the first arm portion 14 and makes surface contact with the curved groove 15. Thus, the first fixture 11 is provided.
Further, a guide groove 16 having the same center as the radius is formed on the upper surface of the first fixture 11, and a screw 17 is screwed to the first arm portion 14 so that the lower end is inserted into the guide groove 16. The

Similarly, the replacement rail R4 has the second fixing member 18 and the second arm portion 19 on one side of the abdomen, the third fixing member 20 and the third arm portion 21 on the other side of the rail R1, and the replacement rail R4. A fourth fixture 22 and a fourth arm 23 are disposed on the other side abdomen.
The first arm portion 14 and the second arm portion 19 are connected by a hydraulic cylinder 24. Similarly, the third arm portion 21 and the fourth arm portion 23 are connected by a hydraulic cylinder 25.

The hydraulic cylinders 24 and 25 are divided into two chambers by a piston that is fixed to one end of piston rods 26 and 27 protruding from the ends of the hydraulic cylinders 24 and 25 and slides in the cylinder, and pressure oil is supplied to each chamber. A motor pump 30 is connected to one end of the hydraulic hose 28 via a switching lever 29.
The protruding portions of the L-shaped first arm portion 14 and the L-shaped third arm portion 21 are connected by a first connecting plate 31.

The first connecting plate 31 is provided so as to be rotatable with respect to the first arm portion 14 and the third arm portion 21 via a connecting pin 32, and both the upper surface and the lower surface of the first collar portion 14 and the third arm portion 21. Provided.
Similarly, the second arm portion 19 and the fourth arm portion 23 are connected by a second connecting plate 33.
With the hydraulic cylinders 24 and 25 extended, the close contact portions 12 of the first fixing tool 11 and the third fixing tool 20 are applied to both sides of the rail R1, while the second fixing tool 18 and the fourth fixing tool 22 are applied to the replacement rail R4. Similarly, set it in contact.

  Next, when the hydraulic cylinders 24 and 25 are contracted, the connecting pins 32 serve as fulcrums, and the arm portions 14, 19, 21, and 23 rotate, and the fixing members 11, 18, 20, and 22 follow this. The curved surface 13 and the curved grooves 15 of the arm portions 14, 19, 21, 23 are advanced in the direction of the rails R1 and R4 in a state where they are in contact with each other, and are firmly fixed to the rails R1 and R4 by pressing each other.

Next, the pressure welding machine D is mounted inside the tensioner C. The pressure welding machine D includes a left clamp support block 51 for clamping one of the two rails R1 and R4 to be connected, a right clamp support block 52 for clamping the other, and a heating burner support block 53. The cylinder support block 54 is supported, and each block is supported by four guide shafts 55 at the upper, lower, left and right corners.
The support block 51 of the left clamp is fixed on the guide shaft 55, but the support block 52 of the right clamp is opposed to the support block 51 and supported so as to be movable on the guide shaft 55, and the support block 53 of the burner is It is located between the support block 51 and the support block 52 and is movably supported by the guide shaft 55.

Two pressure welding cylinders 56 are attached to the support block 54 of the pressure welding cylinder 56 in parallel to the guide shaft 55 at symmetrical positions, and each ram 57 is connected to the support block 52 of the moving clamp. As the ram 57 moves forward and backward, the movable clamp support block 52 is moved along the guide shaft 55 toward the support block 51 of the stationary clamp provided on the guide shaft 55, and the rails R1, C1 clamped on the support blocks 51 and 52 of the respective clamps. R4 is abutted against each other and pressed.
As shown in FIG. 5, each support block 51, 52, 53, 54 is formed with clamp openings 58, 59, burner outlets 60 and rail fitting openings 61 opened downward at the same position. 58, 59, 60, 61 have a size and a shape that allow fitting from the direction of the head R1 of the rail, and the support blocks 51, 52, 53, 54 are connected to the rail R1, R4 from above. The rails R1 and R4 are fitted into the openings 58, 59, 60, and 61 in such a state that they are placed, and the press contact machine D is installed on the rails R1 and R4.

FIG. 5 shows the structure of the stationary clamp support block 51 and the moving clamp support block 52 in detail.
Both support blocks 51 and 52 have the same structure. As shown in the figure, fixed clamp claws 64 and 65 are provided on the inner surfaces of the neck portions 62 and 63 of the support blocks 51 and 52 constituting the clamp openings 58 and 59, respectively. Moving clamp claws 68 and 69 are provided on the inner surfaces of the neck portions 66 and 67 facing the fixed clamp claws 64 and 65, respectively, and the neck portions 66 and 67 provided with the moving clamp claws 68 and 69 are the same. A mounting hole is provided in the position from the side, and the cylinders 70 and 71 are detachably attached thereto, and the moving clamp claws 68 and 69 are attached to the rams 72 and 73 of the cylinders 70 and 71, respectively. The rams 72 and 73 are moved forward and backward by the operation of the cylinders 70 and 71, and accordingly, the moving clamp claws 68 and 69 are moved toward the fixed clamp claws 64 and 65, and the rails R1 and R4 are moved. It is configured to clamp the parts.

  Further, a hot punching blade 76 is attached to the front surface of the support block 52 of the moving clamp, and after the press-contact is completed, the replacement rail R4 of the cylinder 71 is unfixed while the rail R1 is fixed by the cylinder 70. Then, the support block 52 is moved forward by the pressure welding cylinder 56 so that the excess thickness of the entire circumference of the contact portion formed by pressure welding is removed by hot shearing.

When the cylinders 70 and 71 for the clamp claws 68 and 69 are moved by a hydraulic pump or the like, the movable clamp claws 68 and 69 are brought into contact with the abdominal portions of the rails R1 and R4.
Further, when the cylinders 70 and 71 are operated, the machine body is moved in the direction in which the fixed clamp claws 64 and 65 come into contact with the abdomen of the rails R1 and R4 on the other side by the reaction. Clamp in the state of being pinched.
As a result, the street side neck of the rail wheel flange is automatically restricted by the gripping surfaces of the fixed clamp claws 64 and 65, and the street side neck of the wheel flange is regulated by the inner back surfaces of the clamp openings 58 and 59, and the rails R1, R4. Are in a state of being abutted with each other on the street side, and the rail is gripped with high accuracy in a preferable state for passing the wheel.
The pressure welding machine D is not limited to the above-described structure, but may be configured to grip the rails R1 and R4 with another structure.

After attaching the tensioner C and the pressure welding machine D to the rails R1 and R4 as described above, the pressure oil is supplied to the switching lever 29 leading to the motor pump 30 of the tensioner C in the direction in which the piston rods 26 and 27 extend. As shown in FIG. 1, the rails R1 and R4 are extended by gradually applying a tensile force so as to give the planned rail axial pressure calculated from the amount of reduction of the rail when the rail is cut or the rail temperature during work. ). The tensile force is increased to an average by moving the pressure adjustment knob while monitoring a pressure gauge provided in the control box 34.
Then, in a state where the gap between the rails R1 and R4 is eliminated and contacted (T1 in FIG. 1), the contact surface is heated by a burner (not shown) provided on the burner support block 53 (the portion in FIG. ). The burner support block 53 has a burner outlet opening toward the entire outer peripheral surface of the abutting portions of the rails R1 and R4 clamped by the left and right clamping claws, and heats the burner flame intensively toward the entire rail abutting portion. And the joint surface of a rail is joined.

When the burner outlet is not correctly positioned at the center of the contact portion of the rails R1 and R4, the burner support block 53 is moved along the guide shaft 55 to adjust the position so that the correct heating position is obtained.
The gas sent to the burner is adjusted as a mixed gas pressure obtained by mixing oxygen and acetylene through the balancer 74 and is supplied from a supply port 75 provided in the burner support block 53. When heating with a burner, pressure is required.
This pressure contact pressure is dealt with by increasing the pressure of the pressure welding cylinder 56 of the pressure welding machine D and the pressure of the cylinders 24 and 25 of the tensioner C.

That is, in the pressure welding machine D, a constant pressure (pressure γ in FIG. 1) is applied to the rail between the first fixture 11 and the second fixture 18 of the tensioner C. The pressure adjustment of the pressure contact cylinder 56 is performed by a hydraulic operation panel 77.
Further, the tensioner C is given a pressure (pressure β in FIG. 1) obtained by subtracting the pressure γ already applied by the pressure welding machine D from the pressure contact pressure (which is generally 16 to 20 tons depending on the size of the rail). This pressure β is added to the tension pressure by a person who monitors the pressures of the hydraulic cylinders 24 and 25 in the control box 34 after confirming that the rails R1 and R4 are in contact (T _{1 in} FIG. ₁ ).

  After the contact, the contact pressure of the rails R1 and R4 by the tensioner C (pressure β) is added to the contact pressure (pressure γ) of the pressure welding machine D to the center of the contact portion of the rails R1 and R4. (2) in FIG. 1).

  When the burner heating is continued, when the temperature of the contact portion rises and the contact portion reaches a high temperature that cannot support the pressure, the contact surface is crushed and the hydraulic cylinders 24 and 25 of the tensioner C operate. At this time, the pressure drop in the hydraulic cylinders 24 and 25 temporarily occurs. This pressure drop is detected by a pressure switch in the motor pump 30, and the motor pump 30 is automatically driven to supply hydraulic oil into the hydraulic cylinders 24 and 25 (T2 portion in FIG. 1).

By driving the motor pump 30, a sequencer 35 for controlling the control box 34 is operated. The sequencer 35 is controlled by a program so as to increase the pressure of the hydraulic cylinders 24 and 25 of the tensioner C every certain time.
For example, from the start of driving the motor pump 30 to 1 minute, every 6 seconds, from 1 minute to 2 minutes, every 3 seconds, from 2 minutes to 3 minutes, every 2 seconds, after every 3 minutes, 1 second The pressure is increased by 0.5 tons at intervals (C in FIG. 1).

  As the pressure to be increased, a value obtained by dividing a value obtained by subtracting the pressure axial force at the time of contact from the planned axial force calculated from the reduction amount of the rail when the rail is cut or the rail temperature at the time of work is divided by 60 to 120. It is done.

When performing normal gas pressure welding, the contact portion is heated with a burner while pressing the contact surface with a constant pressure. After the burner is heated, the temperature of the contact surface rises to support the pressure pressure. When it disappears, the contact surface is crushed and the pressure is reduced.
In the construction method of this example, the hydraulic control box 77 for controlling the pressure contact pressure is provided with a pressure switch. When a pressure drop of about 10% occurs, the hydraulic pump is activated to supply oil to the pressure contact cylinder 56. A constant pressure contact pressure is maintained on the contact surface.
Thereafter, the operating frequency of the hydraulic pump increases as the temperature of the contact surface increases due to burner heating, and the speed at which the contact portion collapses increases. When the predetermined compression amount is reached, the press contact is finished.

  The frequency of operation of this hydraulic pump is usually 30 to 60 times, although it varies depending on the amount of compression (compression amount is 24 to 30 mm depending on the rail steel type) and the size of the rail (40 to 60 kgf per meter). . As the operation frequency increases, pressurization is performed at a constant pressure, and the quality of the pressure contact portion is improved.

Even in the case of the rail tension gas pressure welding method of the present invention, it is important to always apply a constant pressure pressure to the abutting portion during the heating of the burner.
For this reason, a high-precision pressure switch is installed in the motor pump 30 of the tensioner C, and when the motor pump 30 is activated after a slight pressure drop (T2 in FIG. 1), The number of operations is controlled by the sequencer 35, and the quality of the press contact portion is improved by setting the number of operations to about twice that of the normal press contact.

  In this way, the abutting part is pressurized with a constant pressure β + γ until the temperature of the abutting part is low at the beginning of the burner heating, and when the temperature of the abutting part becomes too high to support the pressure pressure β + γ. In order to maintain the pressure contact pressure β + γ, gradually increase the pressure of the tensioner C over a relatively long time interval, and when the temperature of the contact portion is sufficiently increased, increase the pressure of the tensioner C over a relatively fast time interval. By increasing the pressure, a constant pressure β + γ can be maintained and a good joint can be obtained.

The sequencer 35 further applies a rail pressure contact force β to a pressure obtained by adding a desired pressure to the holding axial force (the axial force of the planned rail in FIG. 1) (the holding axial force of the tensioner outer rail in FIG. 1) in advance. It is programmed so that the buzzer 36 will sound when the pressure becomes high, and at that time the pressure increase of the tensioner C is stopped and held (T3 in FIG. 1). The holding axial force is an axial force generated when the rail end surfaces of the cut rails are matched with each other, and is a value calculated in advance.
When the buzzer rang, the person operating the burner extinguishes the burner, and immediately, the hot punching shearing machine 76 of the pressure welding machine D removes the remaining portion of the pressure welding area by hot shearing, and again the rails R1, R4. And pressure γ is applied. A specific method for calculating the value of the pressure γ will be described later. In addition, you may make it alert | report the time when it became set pressure not only in the structure where the above-mentioned buzzer sounds but in another structure.

After the hot shearing and re-holding of the pressure welding machine D is completed, the program of the sequencer 35 is solved, the control box 34 is operated, the pressure β applied to the tensioner C is released, and the holding shaft pressure is fixed (described later) Only the pressure applied with excessive axial force x) is applied to the outer rail of the tensioner C.
As a result, the pressure in the hydraulic cylinders 24 and 25 of the tensioner C gradually decreases, and the rail axial force necessary for the rail outside the tensioner C is continuously applied (part 2 in FIG. 1).
In addition, a constant pressure γ is continuously applied to the rail inside the tensioner C by the pressure welding machine D (part 2 in FIG. 1).

And after holding this pressure until it cools to the temperature (300 degreeC) which may apply the rail axial pressure of the outer side of the tensioner C to a rail press-contact part, the tensioner C is removed.
By holding this pressure until the pressure γ given by the pressure contactor D is cooled to a good temperature (300 ° C.) by applying an axial force (axial force equalization process) and then removing it, only the holding axial force is applied to the rail. It comes to occur.

The axial force equalization process requires a minimum work time and work amount because the tensioner C does not apply an unnecessarily large axial pressure to the outer rail.
Moreover, since the axial pressure more than necessary is not applied to the rail, it is not necessary to lengthen the rail fastening dismantling performed before attaching the tensioner C.

  The above is the pressure welding method for the cutting point A, but the cutting point B is joined only by the pressure welding machine D without using the tensioner C as described above. Therefore, the pressure contact pressure is given by the operation of the pressure contact cylinder 56 provided in the pressure welding machine D.

FIG. 6 shows a second example of the rail tension gas pressure welding method (corresponding to claim 2). In this example, the pressure γ of the pressure welding machine D is the time when the rails R1 and R4 are in contact (see FIG. 6). Without giving to T1), it is given after the end of burner heating (T3 in FIG. 6). In this case, after the rails R1 and R4 are brought into contact with each other, the tensioning device C is given a pressure pressure (β + γ) obtained by adding the pressure β to the pressure γ as the pressure pressure, and after the burner heating is finished (see FIG. 6). The pressure contact pressure (β + γ) is removed from T3).
Further, the pressure γ is not limited to the pressure welding machine, but may be a compression device such as another hydraulic pump.

  That is, when gas pressure welding is performed by a gas pressure welding machine after the rails come into contact with each other, the gas pressure welding pressure (β + γ) obtained by adding the pressure (γ) to the tension force at the time of contact is added by the tensioner C. While applying a constant pressure contact tension between the rails, the contact portion between the rails is heated to perform the rail pressure contact (the portion shown in FIG. 6B).

  Then, after the contact surfaces of the rails are crushed by the rail pressure contact, the contact portion is heated with the pressure contact tension force that gradually increases the tension force from the tension force at the time of contact, thereby performing the rail pressure contact (FIG. 6). Part of

  When the pressure contact tension reaches a pressure obtained by adding the rail pressure contact force to a predetermined rail axial pressure, heating of the contact portion is stopped to complete the rail pressure contact, and the pressure applied from the pressure contact tension force at the time of contact (β + γ ) And applying a planned axial force to the rail located outside the tensioner, and applying a constant pressure (γ) to the rail inside the tensioner with a gas pressure welder, the tensioner outside and inside An axial force is applied to each of the rails positioned at (2 in FIG. 6).

FIG. 7 shows a third example (corresponding to claim 3) of the rail tension gas pressure welding method. In this example, the pressure γ of the pressure welding machine D is the rails R1, R4 as in the example of FIG. It is made to give after burner heating completion (T3 of FIG. 7), without giving at the time of contact | abutting (T1 of FIG. 7).
The difference from the example of FIG. 6 is that when the pressure tension reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a gas pressure (β + γ), heating of the contact portion is stopped. The rail pressure welding is completed, the pressure (β + γ) applied at the time of contact is removed from the pressure tension force, and a new balanced shaft is added to the pressure obtained by adding the desired pressure to the holding axial force on the rail located outside the tensioner. This is the part that performs the axial force equalization process on the rail of a predetermined length outside the tensioner by applying the pressure to which the force α is applied (part 2 in FIG. 7). And after the gas pressure welding part by said rail pressure welding becomes 300 degrees C or less, provision of the balance axial force (alpha) by a tensioner is stopped, construction of the tensioner and gas pressure welding machine between rails is disassembled, and holding axial force To occur on the rail. A specific method for calculating the value of the balanced axial force α will be described later.

Next, the relationship between the rail axial pressure and the pressure contact pressure in the rail gas pressure welding method shown in FIG. 1 will be described with specific numerical values.
A case where a part of a long rail laid at an air temperature of 30 ° C. (medium temperature) is cut to 0 ° C. (winter) and replaced with a new rail will be described as an example.
When the middle part of a JIS 60kg rail of a long rail (generally 200 m or more) laid at an air temperature of 30 ° C reaches 0 ° C, an axial force of 55.6 tons is generated according to the following formula 1.

(Formula 1)
Axial force P1 = Young's modulus, 60 kg rail cross-sectional area, temperature difference, linear expansion coefficient

^{= 2.1 × 10 3 × 77.4 ×} 30 × 1.14 × 10- 5 ≒ 55.6

Accordingly, when the middle portion of the rail is cut, the force of 55.6 tons is released. Here, if the resistance value r (road bed longitudinal resistance value) is 0.9 ton / m, the rails corresponding to 55.6 / 0.9≈61.8 m are contracted on both rails.
This phenomenon will be described with reference to FIG.
FIG. 8 is a distribution diagram of the axial force in the rail, where the vertical axis indicates the axial force, the horizontal axis indicates the length, the underline indicates the axial force 0 tonf, and the axial force area indicates the axial force × length. Note that the rails on both sides in the figure are not connected. 150 is an axial force of 55.6 tons. 151 is a movable section and is 61.8 m. Reference numeral 155 denotes an opening amount, which is 21 mm according to the following formula 2.

(Formula 2)
Aperture K = Young's modulus, 60 kg rail cross-sectional area, temperature difference, linear expansion coefficient, (temperature difference, linear expansion coefficient) / r
= P1 × (30 × 1.14 × 10- 5) / 0.9 ≒ 21

The end surface 153 and the end surface 154 are the cut rail surfaces.
Here, as shown in FIG. 8 (b), the rail with the scratch A is removed, the 10m rail 156 is inserted, and the fastening devices for the rails on both sides of the rail 156 are loosened 10m at a time to attach the tensioner and the pressure welding machine. A section with an axial force of 0 tonf of about 30 m occurs. Since the movable section 151 corresponds to the axial force 150, it is generated from the end where the fastening device is loosened. That is, in FIG. 8B, the rail of a total of 153.6 m causes a reduction in the axial force, which is twice as long as the section 30 m where the fastening device is loosened and the movable section 151.
Axial force drop section length = 30 + 61.8 x 2 ≒ 153.6

In this state, as shown in FIG. 8C, normal gas pressure welding is performed at the location 159.
Next, a tensioner is set at a position 160 of the rail 157 and a position 161 of the rail 156, a gas pressure welding machine is set at the position 162, and predetermined tension gas pressure welding is performed.

FIG. 8D is an axial force distribution diagram when the tension gas pressure welding is finished.
Here, the total value of the axial force areas 182 and 183 is the same as the total value of the axial force areas 177, 178, 179, and 180.
Also, assuming that the rail length inside the tensioner is 4 m (usually 4 m because one rod 37 and one hydraulic cylinder 24, 25 are connected), the axial forces 172 and 173 are as follows: Become.

Axial force 172 = (Axial force 150 × rail length inside tensioner) / (Axial force drop section length−rail length inside tensioner)
= (55.6 × 4) / (153.6-4)
= 1.49 ≒ 1.5 tonf
This axial force 172 is defined as an excessive axial force x generated on the outside of the tensioner (an axial force corresponding to the desired pressure of claim 1).
Axial force 173 = Axial force 150 + Axial force 172
＝ 55.6 ＋ 1.5 ≒ 57.1 tonf
Further, since the movable section 175 corresponding to the axial force 173 is an axial force / bed bed resistance value, the movable section 175 corresponding to the axial force 173 is 57.1 / 0.9 = 63.4 m.

  In other words, when the tensioner is released, the rail outside the tensioner undergoes a change in axial force by 63.4m from the end of the tensioner. However, the outer axial force areas 177 and 180 are not affected. When the tensioner is released as it is, a decrease in the axial force corresponding to the axial force areas 177 and 180 occurs in the vicinity of the tension gas pressure contact portion.

Total value of the axial force areas 177 and 180 = (Axial force drop section length−rail length inside the tensioner−twice the movable section 175 length corresponding to the axial force 173) · axial force 172
= (153.6-4-63.4 × 2) × 1.5 = 34.2m ・ tonf

Considering only the rail length of 4m where the axial force drop is in the tensioner, the axial force drop value is a large value of 8.6tonf (34.2m · tonf / 4m). Also, dividing by the total value of the movable section length (63.4 × 2m) and the rail length 4m in the tensioner 153.6m, it becomes 0.26tonf.
In any case, when the tensioner is released, the axial force of the movable section decreases as described above.

  For this reason, an axial force area 182 corresponding to the total value of the axial force areas 177 and 180 may be loaded in advance on the rail in the tensioner. Specifically, a total value of 34.2 m · tonf of the axial force areas 177 and 180 may be added to the rail in the tensioner with a gas pressure welding machine. That is, the axial force of 34.2 m · tonf / rail length in the tensioner 4 m≈8.6 tonf may be γ.

  Thus, after gas pressure welding, if the tensioner gives 57.1tonf of axial force to the outer rail of the tensioner and the rail inside the tensioner gives 8.6tonf of axial force by the gas pressure welding machine, then gas pressure welding After that, when axial force equalization processing is performed and the gas pressure welding part becomes 300 ° C. and the tensioner and the gas pressure welding machine are disassembled, the axial force distribution shown in FIG. Does not occur. In addition, although the portion where the axial force is higher by 1.5 tons remains in the sections 174 and 176, since it is very small at 2.7% with respect to 55.6 tons of the axial force 150, there is no problem in maintenance of the long rail. .

The length of the section 174 or 176.
The total length is twice the length of the movable section 175 corresponding to the axial force reduction section length−the rail length inside the tensioner−the axial force 173, so 153.6−4−63.4 × 2 = 22.8 m. The length of the section 174 is (22.8−10) /2=6.4 m because the section 176 becomes longer by the insertion of the 10 m rail. The section 176 is 10 m + 6.4 m = 16.4 m.

Next, the relationship between the rail axial pressure and the pressure contact pressure in the rail gas pressure welding method (corresponding to claim 3) shown in FIG. 7 will be described with reference to specific numerical values.
The description will be made under the same conditions as above. FIG. 9A is an axial force distribution diagram when the gas pressure welding is finished.

The axial force 196 is in a state where the gas pressure welding is finished, (β + γ) is taken from the tension force, and the balanced axial force α is newly added to the holding axial force to be tensioned.
Here, the total value of the axial force areas 183 is the same as the total value of the axial force areas 187, 188, 189, 190, 191, 192, 193, 194.
The axial force 172 is calculated as follows in the same manner as described above.

Axial force 172 = (Axial force 150 × rail length inside tensioner) / (Axial force drop section length−rail length inside tensioner)
= (55.6 x 4) / (153.6-4)
= 1.49 ≒ 1.5 tonf
The axial force 196 is as follows.
Axial force 196 = Axial force 150 + Axial force 172 + Axial force 195
= 55.6 + 1.5 + α ≒ 57.1 + α
Here, when the balanced axial force α is 0.26 tons, the axial force is 196≈57.36 tons.

The balanced axial force α is obtained by the following formula.
Axial force area in the tension device (4m x axial force)
＝ {(Excessive axial force x + α) ・ Double of movable section length to (Axial force + excessive axial force x + α)} ＝ {(Excessive axial force x + α) ・ (Axial force + excessive axial force x + α) / Road bed longitudinal resistance force}・ 2
If you turn this into a formula,
4 × P1 = {(x + α) × (P1 + x + α) / r} × 2
It becomes.
Of these, 188, 192, 189, and 193 are expressed by the following equations as the axial force area.
{(P1 + x + α) / r} × (x + α) × 2 (1)
Further, the axial force area of 183 is expressed by the following equation.
P1 × 4 (2)
If (1) and (2) are balanced, the axial force does not decrease.
here,
P1 = Young's modulus, 60 kg rail cross section, temperature difference, linear expansion coefficient (tonf)
x = 4 · P1 / {(2 · P1 / r) + (Q−4)} (tonf)
Q = Length of the section where the axial force becomes 0 tonf at the time of dismantling before fastening (m)
Since the values of P1, x, and Q are calculated as described above, the value of the balanced axial force α can be obtained by substituting each value.

4 × 55.6 = {(1.49 + α) (55.6 + 1.49 + α) /
0.9} × 2
= {(1.49 + α) (57.09 + α) /
0.9} × 2
100.08 = {(1.49 + α) (57.09 + α)
0 ≒ α ² + 58.58α-15.02
≒ (α + 58.32) (α−0.26)
Therefore, the value of α is −58.32 or +0.26. Since the value of − is not appropriate, the balanced axial force α≈0.26.

The movable section 185 corresponding to the axial force 196 is 57.36 / 0.9 = 63.7 m because of the axial force / bed bed resistance value.
In other words, when the tensioner is released, the rail outside the tensioner undergoes a change in axial force by 63.7 meters.
From this, the total value of the axial force areas 188, 192, 189, and 193 is (axial force decreasing section length · 2) · (axial force 172 + axial force 195), so (63.7 × 2) × (1.5 + 0.26) ≒ 224.2m ・ tonf.
Since this value is substantially equal to the rail axial force area 4m × 55.6 = 222.4 in the tensioner, when the tensioner is disassembled, the axial force of the rail in the tensioner is compensated.

  By this, after gas pressure welding, if the axial force of holding axial force + excess axial force x + uniform axial force α is given to the rail outside the tensioner with a tensioner, axial force equalization processing is performed after gas pressure welding. When the gas pressure welding part is 300 ° C. and the tensioner and the gas pressure welding machine are disassembled, the axial force distribution shown in FIG. 9B is obtained, and the axial force drop in the middle part of the long rail does not occur. In addition, portions where the axial force is higher by 1.76 tons remain in the sections 184 and 186. Although this value is larger than the above-described method (corresponding to claim 1), it is very small as about 3% with respect to 55.6 tonf of the axial force 150, so there is no problem in maintenance of the long rail.

The length of the section 184 or 186.
The total length is twice the movable section 185 corresponding to the axial force drop section length−the rail length inside the tensioner−the axial force 196, so 153.6−4−63.6 × 2 = 22.4 m.
Since the section 186 becomes longer by the insertion of the 10 m rail, (22.4−10) /2=6.2 m is the length of the section 184. The section 186 is 10 m + 6.2 m = 16.2 m.

In the above-mentioned rail tension gas pressure welding method, the holding axial force is calculated as “axial force generated when the rail end faces of the cut rails are matched”, but depending on the usage situation after rail laying, the axial force A phenomenon occurs in which changes partially.
This is because the long rail immovable section is laid so that the same axial force is applied to any part, but after use, this axial force will cause the roadbed to deteriorate, the fastening device to deteriorate, the rail to advance by passing through the train, and direct sunlight. This is because it may change depending on causes such as a location that hits and a location that does not hit.
In such a case, in the above-described rail tension gas pressure welding method, in consideration of the laying state of the rail, it is calculated as a value different from the axial force generated when the rail end surfaces of the cut rail are matched. Also good.

That is, when the axial force calculated from the opening amount when the rail is cut is, for example, 10 tons lower than the management axial force for maintenance, the value obtained by adding 10 tons to the axial force calculated from the opening amount is used as the holding axial force. It is only necessary to perform tension gas pressure welding by each of the methods, and perform axial force equalization processing and tension device dismantling.
Conversely, if the axial force calculated from the opening amount when the rail is cut is 10 tons higher than the management axial force for maintenance, for example, the holding axial force is obtained by subtracting 10 tons from the axial force calculated from the opening amount. As described above, the tension gas pressure welding is performed by the above-described methods, and the axial force equalization process and the tensioner dismantling are performed.

  The method of the present invention provides a uniform axial force to the rails to be replaced and the rails before and after the rails when the rails in which defective portions are generated are exchanged at a medium temperature or lower. And the amount of work can be simplified, and the reliability of the joint in the pressure welding can be increased.

It is a graph which shows the pressure concerning the joint surface of the rail by this invention construction method. It is plane explanatory drawing which shows the implementation condition of this invention construction method. It is sectional explanatory drawing of the tension device part used with this invention construction method. It is front explanatory drawing of the pressure welding machine part used with this invention construction method. It is sectional explanatory drawing of the press-contacting machine part used by this invention construction method. It is a graph which shows the pressure concerning the junction surface of the rail by the other example of this invention construction method. It is a graph which shows the pressure concerning the junction surface of the rail by the other example of this invention construction method. (A) thru | or (e) is a schematic diagram which shows the axial force distribution map in a rail at the time of cut | disconnecting a rail. (A) And (b) is a schematic diagram which shows the axial force distribution figure in a rail at the time of cut | disconnecting a rail. (A) (B) is a plane explanatory view for explaining the joining method of rail exchange of the present invention. (A) (B) is a plane explanatory view for explaining the joining method of the conventional rail exchange. (A) thru | or (e) is a schematic diagram which shows the axial force distribution map in a rail at the time of cut | disconnecting a rail. (A) thru | or (c) are schematic diagrams which show the axial force distribution map in the rail at the time of cut | disconnecting a rail.

Explanation of symbols

R1, R2, R3 rail R4 exchange rail C tensioner D pressure welding machine 24, 25 hydraulic cylinder 26, 27 piston rod 30 motor pump 30
34 Control box 35 Sequencer 56 Pressure welding cylinder

Claims (5)

In the method of cutting the defective part rail that occurred in the long rail immovable section and replacing it with a new rail,
While calculating the axial force generated when the rail end surfaces of the cut rails are matched with each other as a holding axial force,
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails A first step of giving tension to
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a constant pressure (γ) is applied to the rail located inside the rail tensioner by the gas pressure welding machine and tension is applied. For rails located outside the vessel, the rail pressure (β) is obtained by subtracting the pressure (γ) already applied to the rail located on the inside from the gas pressure, in addition to the tension at the time of contact. A second step of heating the contact portion between the rails and performing the rail pressure welding while giving a certain pressure welding tension force between the rails,
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. When,
When the pressing tension force reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a rail pressing force (β), heating of the contact portion is stopped to complete the rail pressing, and the pressing tension The pressure (β) applied at the time of contact is removed from the force, and only the pressure obtained by adding the desired pressure to the holding axial force is applied to the rail located outside the tensioner, and the rail located inside the rail tensioner A fourth step of performing an axial force equalization process on a predetermined length of the rail outside the tensioner by continuing to apply the pressure (γ) to the rail with a gas pressure welding machine,
A fifth step of disassembling the tensioner and the gas pressure welding machine between the rails after the gas pressure welding part due to the rail pressure welding is 300 ° C. or less, and causing the holding axial force to be generated in the rail;
Rail tension gas pressure welding method comprising
In the method of cutting the defective part rail that occurred in the long rail immovable section and replacing it with a new rail,
While calculating the axial force generated when the rail end surfaces of the cut rails are matched with each other as a holding axial force,
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails A first step of giving tension to
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a certain pressure (γ) is added to the rail located outside the tensioner in addition to the tension force at the time of contact. A second step of performing rail pressure welding by heating a contact portion between the rails while applying the gas pressure pressure (β + γ) as a constant pressure tension between the rails,
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. When,
When the pressing tension reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a gas pressure (β + γ), heating of the contact portion is stopped to complete rail pressure welding, and the pressure tension The pressure (β + γ) applied at the time of contact is removed from the force, and only the pressure obtained by adding the desired pressure to the holding axial force is applied to the rail located outside the tensioner, and the rail located inside the rail tensioner A fourth step of performing an axial force equalization process on a rail of a predetermined length outside the tensioner by applying a pressure equal to the pressure (γ) to the rail with a predetermined length;
A fifth step of disassembling the tensioner and the gas pressure welding machine between the rails after the gas pressure welding part due to the rail pressure welding has become 300 ° C. or less, so that the holding axial force is generated in the rail;
Rail tension gas pressure welding method comprising In the method of cutting the defective part rail that occurred in the long rail immovable section and replacing it with a new rail,
While calculating the axial force generated when the rail end surfaces of the cut rails are matched with each other as a holding axial force,
Join one end of the replacement rail to one of the long rail cut points, and install a rail tensioner and gas pressure welder between the other end of the replacement rail and the other long rail cut point, and gradually increase between the rails A first step of giving tension to
When gas pressure welding is performed by the gas pressure welding machine after the rails are in contact with each other, a certain pressure (γ) is added to the rail located outside the tensioner in addition to the tension force at the time of contact. A second step of performing rail pressure welding by heating a contact portion between the rails while applying the gas pressure pressure (β + γ) as a constant pressure tension between the rails,
After the contact surfaces of the rails are crushed by the rail pressure contact, a third step of performing the rail pressure contact by heating the contact portion with the pressure tension force gradually increasing the tension force from the tension force at the time of the contact. When,
When the pressing tension reaches a pressure obtained by adding a desired pressure to the holding axial force and adding a gas pressure (β + γ), heating of the contact portion is stopped to complete rail pressure welding, and the pressure tension The pressure (β + γ) applied at the time of contact is removed from the force, and a pressure obtained by adding the balanced axial force α to the pressure obtained by adding the desired pressure to the holding axial force to the rail located outside the tensioner is applied. Then, a fourth step of performing axial force equalization processing on the rail of a predetermined length outside the tensioner,
After the gas pressure contact portion due to the rail pressure contact becomes 300 ° C. or less, the application of the balanced axial force α by the tensioner is stopped, the construction of the tensioner and the gas pressure welder between the rails is disassembled, and the holding axial force is A fifth step to occur in
Rail tension gas pressure welding method comprising In the third step, when the rail contact portion is heated to perform the rail pressure contact, the pressure contact tension force is controlled so that a constant pressure contact pressure is always generated in the contact portion. Rail tension gas pressure welding method described. 4. The rail tension according to claim 1, wherein the holding axial force is calculated as a value different from an axial force generated when the rail end surfaces of the cut rail are matched in consideration of a rail laying state. Gas pressure welding method.

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