JP5123740B2 - Manufacturing method of rail joint plate for connection between no play - Google Patents

Description

  The present invention relates to a method for manufacturing a rail joint plate for connection between no-plays in which rails are brought into close contact with each other by a shape restoring force of a shape memory alloy so as not to cause a gap between adjacent rails in series.

  The rails are most commonly connected to each other after the rail ends to be connected with each other, with the two seam plates placed on both sides of the rail and tightened with bolts and nuts. However, in this method, as shown in FIG. 14, the gaps G1 called gaps between the rails after being connected due to a slight misalignment of the bolt holes between the rails 18 and 19 and the rail joint plate, etc. Occurs.

  This gap becomes a cause of generating shocking vibration and noise in the vehicle traveling on the rail. Particularly shocking vibrations are repeatedly applied to both the vehicle and the rail, causing the end of the rail to be lost. Also, on the side of the vehicle traveling on the rail, especially in the case of a crane that transports heavy objects, the suspended load is vibrated and there is a risk of dropping the suspended load. It is also known to cause major accidents that damage control systems.

One method for preventing gaps between the rails is a method in which the rails are directly welded and connected without using a joint plate. If the rail ends are welded together, there will be no gap, but not only is it necessary to have a highly qualified technician work on the rails, but the rails are generally made of high-carbon steel that is difficult to weld. For this reason, including the post-preheating heat work before and after welding requires a long time of 7 to 8 hours for welding at one place.
For this reason, rails are laid (or replaced) according to a long-term plan, and recently, welding is limited to rails for which welding work can be carried out in advance in the space next to existing tracks. Connection by is becoming mainstream.
However, since crane rails are often laid in a narrow space in a high place in a building, it is difficult to secure space for welding work, and when crane rails are welded together, the crane rails can be replaced. Due to the difficulty, even if there is an inconvenience of occurrence of play, many cases rely on connection methods using rail joint plates.

  As described above, there is always a demand for a connection method that does not cause a gap in the rail connection, but in reality the welding method is not effective in all cases. Therefore, when connecting, it can be connected in a short time with the rail joint plate and the bolt and nut, and there is no gap, and when replacing the rail, the bolt can be loosened so that it can be returned to the short rail and easily removed from the high place. There was a strong demand for a simple connection method.

  As a connection method as described above, it is possible to meet such expectations by using a joint plate made of a shape memory alloy to which a shape memory effect is imparted. Shape memory alloys have the property that even if an external force is applied to a previously memorized shape to change the shape, the shape memory alloy will return to the memorized shape before deformation only by heating to an appropriate temperature.

  Therefore, after applying tensile deformation in the length direction in advance and applying the shape memory alloy joint plate with the shape memory effect to both sides of the rail and connecting it loosely with bolts and nuts, heat is applied to the joint plate portion. In addition, it is known that the joint plate is contracted in the length direction and the rails adjacent in series are pulled together to eliminate the gap between the rails (for example, Japanese Patent Laid-Open No. 55-119207).

  Further, if the shape memory processing for the rail joint plate is appropriately performed, it is possible not only to make the gap zero, but also to apply a certain compressive stress to the connection portion of the rail. For example, as shown in FIGS. 13A and 13B, if an appropriate compressive force is applied to the connecting portions of the rails 18 and 19 by the rail joint plate 24 made of shape memory alloy, the vehicle travels on the rail joint portion. It is known that even if a stress that tries to separate the rails is generated at the time of sudden start or stop, it is possible to overcome the stress and always maintain zero clearance (for example, Japanese Patent Application Laid-Open No. 2006-257707). Issue gazette).

  In the above case, after the same connection work as the conventional rail joint plate made of ordinary steel material, the rail joint plate is heated to an appropriate temperature, and the gap is maintained at zero. The joining method using the rail joint plate made of shape memory alloy to which the shape memory effect as described above is imparted has no special skill and the working time is overwhelmingly shorter than the joining method by welding. It is an excellent method, and it is becoming established centering on rail connection methods for crane rails.

  By the way, as a manufacturing method of the shape joint made of shape memory alloy for the non-free joint with the shape memory effect as described above, the shape memory is manufactured even though it is made of a special material called shape memory alloy. Manufactured by a general manufacturing method for alloy products.

In the case of an iron-based shape memory alloy, for example, a shape memory alloy containing 28% Mn, 6% Si, 5% Cr and the balance being Fe, even if the melting point is as high as around 1330 ° C., a temperature lower than that, For example, in a high-temperature region exceeding 1250 ° C., severe embrittlement occurs due to partial dissolution of segregation parts and the like. On the other hand, in a low temperature region below 900 ° C., the deformation resistance becomes very high and the processing becomes difficult. The characteristics of such an iron-based shape memory alloy are completely different from those of general carbon steel that can be hot-extruded in a state of being homogeneous austenite having a sufficiently low deformation resistance by heating to a high temperature region of 1150 ° C. or higher.
In addition, at 900 degrees or less, the processed shape memory alloy crystal particles remain in a crushed state, and thus it is necessary to heat them in order to granulate the crystal particles. The characteristics of such an iron-based shape memory alloy are completely different from general carbon steel that can be hot-extruded in a homogeneous austenite state in which the deformation resistance is reduced in a temperature range of 1250 ° C. or higher.

In the case of specifically processing an iron-based shape memory alloy material having the above-mentioned characteristics, as shown in the flowchart of FIG. 7, it has been manufactured by the following procedures (1) to (8). .
(1) Bar material with a rectangular cross-section (shape of rectangular cross-section) that can be formed by hot-rolling a shape memory alloy material into a plate shape or hot forging into a shape steel shape and cutting out the cross-sectional outline of the joint plate with a margin Steel) 25 (see FIG. 9A).
(2) The bending of the rolled or forged bar material 25 having a rectangular cross section is performed.
(3) A solution heat treatment is performed to remove the strain applied in the forging or rolling process of the bar member 25 having a rectangular section that has been rolled or forged, and to decompose precipitates.
(4) The bar member 25 having a rectangular cross section is cut into a predetermined length as one rail joint plate having a rectangular cross section.
(5) One rail joint plate having a rectangular cross section is pulled and deformed to give a shape memory effect.
(6) As shown in FIG. 9 (b), four inclined surfaces with a rectangular cross section are roughly processed, and the engaging inclined upper surface 26 that engages with the rail head lower surface and the engaging inclined that engages with the rail flange upper surface. A rough-processed rail joint plate 28 having an octagonal cross section provided with a lower surface 27 is provided.
(7) The bolt hole (14-17) is drilled in the rough rail joint plate 28.
(8) In the cross-section, the top, bottom, left, and right four surfaces are finished to make a product of one shape memory alloy rail joint plate 24 to which a shape memory effect is imparted.

More specifically, the shape of this state is memorized by performing the heat treatment of the solution treatment. Next, as shown in FIG. 8, as described above, the bar material 25 having a rectangular cross section is cut into the length of the bar material 25, and the grip members 22 at both ends of the bar material 25 are gripped one by one. The tensile strain of is added. In hot rolling, it is a long bar material so that the cross section is rectangular, but since the cross-sectional dimension in the longitudinal direction varies, in order to open the bolt hole at the correct position in the next step The four-side rough machining is performed as a preliminary cutting process for making a material having a non-uniform shape into a rectangle of a certain size.
In addition, since the said grip part is wrinkled, the part will be cut and removed, and a material loss will be accompanied.
JP-A-55-119207 JP 2006-74746 A

When a seam plate is manufactured from a rail bar material made of a shape memory alloy having a rectangular cross section, there are the following drawbacks or problems.
(1) Unnecessary cross section is cut to produce a rail joint plate with an irregular cross section from a rectangular cross section, resulting in a large material loss (approximately 20% or more) and occurring during tensile processing. There is a problem in that the yield drop is large and the material yield is low in order to remove the grip scratches.
(2) Since the bar material for the rail joint plate having a rectangular cross section is pulled one by one, it is necessary to set and remove the bar material. Therefore, there is a problem that the work is troublesome and the manufacturing efficiency is low.

As mentioned above, since the raw material rolled into the rectangular cross section with a margin with the rolling mill for plates and shape steels is cut and used at present, the yield is deteriorated. In addition, in order to pull after cutting into one sheet, a grip portion is required for each sheet, which is also a major cause of decreasing the yield.
The present invention can simplify the manufacturing process by eliminating the cutting process in manufacturing the rail joint plate made of the shape memory alloy to which the shape memory effect is imparted, and can improve the yield of the material and is more inexpensive. It aims at providing the manufacturing method of the rail joint board made from the shape memory alloy to which the shape memory effect was provided.

In order to advantageously solve the above-described problem, in the rail joint plate manufacturing method according to the first aspect of the present invention, a shape memory alloy rail joint plate for connection between non-plays which is connected so as not to cause play between adjacent rails in series. In the manufacturing method, a cross-sectional outline slightly larger than the cross-sectional outline of the shape memory alloy rail joint plate by hot extrusion at a temperature of 1050 ° C. to 1200 ° C. of an iron-based shape memory alloy material, After forming into a long steel having a length equal to or more than the length corresponding to a plurality of seam plates, the tensile deformation necessary to give a shape memory effect over almost the entire length of the long steel is performed. It is characterized by being applied at a temperature of 0 ° C. or more and 50 ° C. or less , and then cutting the long steel to which the tensile deformation is applied.
According to a second aspect of the invention, in the method for manufacturing a shape seam alloy rail joint plate for connection between no-plays according to the first aspect of the invention, the steel plate is formed into a long steel having a length equal to or greater than the length corresponding to a plurality of joint plates. after, the corrected by bending the tensioning straightening machine profiled length steel, then subjected to solution heat treatment in the state of the long section steel, then back in again tensioning straightening machine, shape memory A tensile deformation necessary for imparting an effect is imparted by the tensile bending straightener.
According to a third aspect of the present invention, in the method of manufacturing a shape seam alloy rail joint plate for connection between no-plays according to the first aspect of the invention, the steel plate is formed into a long steel having a length equal to or more than a length corresponding to a plurality of joint plates. After that, the bending of the long steel is corrected with a tension type bending straightener, and then the shape memory effect is obtained over almost the entire length of the long steel without solution heat treatment of the long steel. It is characterized by imparting tensile deformation necessary for imparting.
In the fourth invention, in the manufacturing method of the shape seam alloy rail joint plate for connection between no-plays of the first invention or the second invention, the tensile deformation step necessary to give the shape memory effect is 950 at 300 ° C. or more. It is characterized by being repeated twice or more with a heat treatment to a temperature range of ℃ or less.
According to a fifth aspect of the invention, in the method of manufacturing a shape memory alloy rail joint plate for non-play connection according to any one of the first to fourth aspects of the invention, the iron-based shape memory alloy material is Fe, Mn, It is an iron-based shape memory alloy mainly composed of Si.
According to a sixth aspect of the invention, in the method of manufacturing a shape memory alloy rail joint plate for non-play connection according to any one of the first to fourth aspects of the invention, the iron-based shape memory alloy material is Fe, Mn, It is an iron-based shape memory alloy mainly composed of Si and Cr.

According to the first invention, a long shape having a length equal to or more than a length corresponding to a plurality of seam plates is obtained by hot extrusion of an iron-based shape memory alloy material at a temperature of 1050 ° C. to 1200 ° C. After forming into steel, the tensile deformation necessary for imparting the shape memory effect is applied and cut at a temperature of 0 ° C. or more and 50 ° C. or less, so that a rail joint plate made of shape memory alloy for non-free connection is manufactured. In this case, since the cutting process can be omitted, it is possible to easily manufacture a seam plate that is approximately 30% less expensive than the conventional case.
In the case of the present invention, since the rail joint plate is manufactured by a process including the hot extrusion method, it is possible to manufacture a joint plate having a different cross-sectional shape as appropriate by changing the extrusion die. Become more flexible.
Furthermore, in the case of the present invention, a rail joint plate made of shape memory alloy by hot extrusion can be obtained in a state where deformation resistance is low and embrittlement is effectively prevented.
According to the second invention, after forming into a long steel having a length equal to or more than the length corresponding to a plurality of joint plates, the bending of the long steel is corrected by a tensile bending straightener, then subjected to solution heat treatment in the state of the long section steel, then back in again tensioning straightening machine, so imparting the straightener bend the tension formula tensile deformation required to impart shape memory effect In addition to the effects of the first aspect, a high-quality shape memory alloy rail joint plate for connection between amusements can be reliably manufactured.
According to the third invention, the tensile deformation necessary to impart the shape memory effect is imparted over almost the entire length of the long steel without subjecting the long steel to solution heat treatment. This can be simplified, and the manufacturing cost of the shape memory alloy rail joint plate for connection between no-plays can be further reduced.
According to the fourth invention, the step of imparting the tensile deformation necessary for imparting the shape saving effect is repeated two or more times with a heat treatment to a temperature range of 300 ° C. or higher and 950 ° C. or lower, Excellent shape recovery performance can be imparted by the long shape steel made of shape memory alloy.
According to the fifth or sixth invention, the non-free connection of the iron-based shape memory alloy mainly composed of Fe, Mn and Si or the iron-based shape memory alloy mainly composed of Fe, Mn, Si and Cr. The shape seam alloy rail joint plate can be manufactured at a much lower cost than the conventional case.

  Next, the present invention will be described in detail based on the illustrated embodiment.

  First, in the present invention, as shown in FIG. 3, a columnar billet 1 made of a shape memory alloy having a volume equal to or more than the volume of a shape memory alloy rail joint plate for connection between no-plays from a shape memory alloy material. Is produced.

As a material of the columnar billet 1 made of a shape memory alloy for manufacturing the above-mentioned shape memory alloy rail joint plate for connection between non-plays, for example, an iron-based shape memory alloy having sufficient basic characteristics as a structural material, For example, an Fe—Mn—Si alloy is one of the most suitable. Typical component compositions of Fe-Mn-Si alloys include Fe-16% Mn-5% Si-12% Cr-5% Ni, Fe-20% Mn-5% Si-8% Cr-5%. Ni, Fe-28% Mn-6% Si-5% Cr and the like. For example, when Fe-28% Mn-6% Si-5% Cr alloy is used as a rail joint plate made of shape memory alloy for non-free connection, the tensile strength is 680-1000 N / mm ² and the shape is completely It has properties such as a transformation temperature of 300 to 350 ° C. and a shape recovery stress of about 180 N / mm ² . Incidentally, the amount of tensile deformation for imparting the shape memory effect may be about 4% to 9%.
In addition, in the Fe-Mn-Si type shape memory alloy, after applying these tensile deformations, heating from 400 ° C to about 800 ° C to about 900 ° C, followed by further applying about 4 to 7% tensile deformation. In this case, it is known that a larger amount of shape recovery can be taken out (called training), and this utilization is also effective for the shape memory alloy rail joint plate for connection between no-plays of the present invention.

  When the columnar billet 1 is in a normal temperature state, as shown in FIG. 3B, the columnar billet 1 is supported so as to be movable up and down, inserted into the heating furnace 2 and heated to a predetermined temperature. The columnar billet 1 is heated to a region, and the temperature is increased to a temperature region where extrusion can be performed.

The temperature range at the time of the hot extrusion molding is preferably set to a range of 1050 ° C. to 1200 ° C. at a temperature not higher than the melting point (for example, 1330 ° C.) of the shape memory alloy.
The reason for this is that the iron-based shape memory alloy as described above has a high deformation resistance in a high temperature range as compared with a normal steel material, and is higher than SUS304 at 1050 ° C. or less, and thus has a large resistance at the time of injection injection. It becomes too much and cannot be injected. On the other hand, it is known that when the temperature exceeds 1250 ° C., the shape memory alloy material becomes brittle. Therefore, in order to take advantage of the characteristics of the iron-based shape memory alloy, it is necessary to manage the hot extrusion molding at an injection temperature in the range of 1050 to 1200 ° C. Preferably, in order to obtain a state close to a homogeneous structure, the temperature during hot extrusion may be controlled in the range of 1050 ° C to 1150 ° C.

Next, the columnar billet 1 heated to such a temperature is placed in a hot extrusion molding apparatus 3 as shown in FIG. 3, and is extruded from a die 5 by a hydraulic pusher 4, and FIG. As shown to (a), while making it the elongate steel 6a which has the length more than the length dimension equivalent to the joint plate for several pieces, the cross-sectional external shape is an inner figure or figure in FIG.2 (d). 2 (b) (c) is slightly larger than the cross-sectional profile of the shape memory alloy rail joint shape steel 6b (or shape memory alloy rail joint plate 7) shown in FIG. It is formed into a long steel 6a having a cross-sectional outer shape shown in (a).
The form shown in FIG. 2 (c) is a cross-sectional form of the long steel 6b at the time of the first tensile deformation in the case of training for tensile deformation again after tensile deformation, and is shown in FIG. 2 (b). The initial tensile deformation may be smaller than the case where the tensile deformation is performed only once.

  As can be seen from FIG. 2 (d), in the present invention, a long steel having a cross-sectional profile slightly larger than the cross-sectional profile of the finished rail joint plate is obtained by hot extrusion from the columnar billet 1 once. 6a is manufactured, and a rail joint plate 6b made of shape memory alloy for connection between non-plays is manufactured by one-time tensile deformation from the long steel 6a. As described above, in order to produce the long steel 6a having a cross-sectional outline slightly larger than the cross-sectional outline of the finished rail joint plate by one hot extrusion, the inner cross-sectional form of the extrusion die 5 is used. Is slightly larger than the cross-sectional profile of the finished rail joint plate.

The reason why the cross-sectional form is slightly larger than the cross-sectional outer shape of the rail joint plate in the completed state as described above is because of the following reasons.
The tensile deformation added to bring out the shape memory effect to the long shape steel 6a having a length dimension equal to or more than a plurality of the seam plates is a certain range of strain in the length direction (type of shape memory alloy However, in the case of Fe—Mn—Si alloy, it is required to be about 4 to 9%). Since this tensile deformation occurs under almost constant volume, both the thickness and the width become smaller with the tensile deformation.
In other words, if the material is made in a size that exactly matches the cross-sectional shape (cross-sectional outer shape) of the seam plate product in the hot extrusion stage, the cross-section of the material becomes smaller than the standard dimension after tensile deformation.
Therefore, when manufacturing shape memory alloy joint plate shape steel 6a by hot extrusion, the ratio of change in cross-sectional shape (outer shape) due to tensile deformation is expected, and the shape has a larger cross-section. This is because it is necessary to obtain steel after hot extrusion.

The present inventor, for the ratio of change in the cross-sectional shape (outer shape), the cross-sectional outer shape of the shape memory alloy joint plate shape steel 6a in the hot extrusion stage gives tensile deformation after hot extrusion. As a result of investigating in detail how it changes, the thickness of the shape memory alloy joint plate 7 of the standard size shown in the left side of the figure is 28 mm and the width direction is 85 mm. In some cases, the shape memory alloy joint plate is (1.05 ± 0.01) times the thickness of the joint plate product, and the plate width dimension is (1.07 ± 0.01) times the joint plate product width. It has been found that it becomes a structural steel 6a.
Then, it has been found that if the extrusion molding is performed in consideration of the change as described above, a cross-sectional outline close to that of the seam plate product can be realized after substantially tensile deformation.

  As described above, the columnar billet 1 of the shape memory alloy is hot-extruded in a temperature-controlled state, and the long steel 6a having a length dimension equal to or more than a plurality of seam plates is used. The reason is that, by one hot extrusion, it becomes possible to produce a long steel 6a having a length of a plurality of rail joint plates, which leads to an improvement in yield. A columnar billet 1 corresponding to the length of the seam plate is used. The cross-sectional form of the columnar billet 6 may be, for example, a circle or a rectangle.

When the long steel 6a processed from the columnar billet 1 is not bent, the long steel 6a is cooled to 50 ° C. or lower and 0 ° C. or higher to cover almost the entire length of the long steel 6a. By applying the tensile deformation necessary for imparting the shape memory effect, the long steel material 6b provided with the tensile deformation necessary for imparting the shape memory effect is obtained, and then the long steel having the tensile deformation applied thereto. After cutting 6b to the state immediately before one seam plate having a predetermined length, a bolt hole is drilled to manufacture a rail joint plate 7 made of a shape memory alloy to which a shape memory effect is imparted. .
In addition, when it cools to the temperature below 0 degreeC, a martensitic transformation will occur and the outstanding shape memory effect will no longer be acquired. At temperatures exceeding 50 ° C., stress-induced martensitic transformation that contributes to the shape recovery phenomenon hardly occurs, and an excellent shape memory effect cannot be obtained.

However, since the hot extrusion molding method is a manufacturing method in which large bending is generally generated, bending occurs in the long steel 6a processed from the columnar billet 1 as described above. For this reason, a straightening machine for correcting the bending, for example, tension, is applied to the long steel 6a having the side surface shape of FIG. 1 (a) and the sectional shape of FIG. 2 (d) outside or the sectional shape shown in FIG. 2 (a). The bending of the long steel 6a is corrected by a “bending corrector” such as a straightening machine, a roller straightening machine, or a pressure straightening machine (see FIG. 4 or FIG. 15).
As the bend straightening machine, for example, a bend straightening machine 8 as shown in FIG. 15 may be used. The bend straightening machine 8 includes an annular furnace 10 having traveling rolls 9 on the entrance side and the exit side. A wire rope 11 is connected to the annular furnace 10, and the wire rope 11 is wound up by a winch 12 from the front and rear surfaces. Alternatively, the annular furnace 10 can be heated uniformly over the entire length using the long steel 6a as a rail by unwinding. Note that the chucking tool 33 held by the holding frame 34 and the long steel 6a are joined by bolt joining or welding. In addition, a rail may be laid along the long steel 6a, and the annular furnace 3 may be run on the rail.

As means for imparting tensile deformation to the long steel 6a in the state cooled to 50 ° C. or lower and 0 ° C. or higher, as shown in FIG. 16 (a), to hold the end of the long steel 6a. A hydraulic tensioning device 29 having a structure in which a clamp 20a having a fixed position and a movable clamp 20b on both sides are connected to each other by a hydraulic jack 21 may be used. .
As described above, the long shape steel 6a is imparted with tensile deformation, and is provided with the tensile deformation necessary for imparting the shape memory effect over almost the entire length, thereby providing the long shape with the shape memory effect. Let it be steel 6b.
Thereafter, the long steel 6b to which the tensile deformation is applied and the shape memory effect is applied is cut into the length of one rail joint plate, and the tensile deformation is applied to provide the shape memory effect to the rail. The joint plate 7 is used. Thus, after making it the state just before one seam board of a predetermined length dimension, bolt hole 14-17 is drilled and the rail seam with a bolt hole made from a shape memory alloy to which a shape memory effect was given. The plate 13 is manufactured.

As described above, when the long shape steel 6a made of shape memory alloy is manufactured by the hot extrusion method, the following advantages are obtained as a secondary.
In the above-mentioned hot extrusion factory, it is common to have a straightening machine for correcting a bend that occurs regularly, for example, a "bend straightening machine" such as a tension straightening machine, a roller straightening machine, or a pressure straightening machine. Therefore, the present inventors pay attention to the tension straightening machine, and the hot straightening machine in the hot extrusion factory uses both ends of the hot extruded product (the long steel 6a). The bend is corrected by grasping and applying a tensile strain of about several percent. The inventors of the present invention applied this tension straightening machine to a long shape steel 6a made of a shape memory alloy as it was before being cut into a length equivalent to one joint plate product 6a. On the other hand, when it is used for imparting the tensile deformation necessary for shape memory, it leads to the efficient production of the shape memory alloy rail joint plate 13 for non-play connection.

When carrying out the present invention, when applying the above-described tensile deformation, the step of applying the tensile deformation necessary to impart the shape recording effect is a heat treatment to a temperature range of 300 ° C. or higher and 950 ° C. or lower. You may make it repeat it 2 times or more on both sides.
The tensile deformation in this case may include bending correction by a tension corrector.
The reason for performing the heat treatment to a temperature range of 300 ° C. or more and 950 ° C. or less is that the temperature range of 300 ° C. or less cannot cause sufficient shape recovery, so that the next tensile deformation stores a new shape. Will no longer function as an effective deformation. If the temperature exceeds 950 ° C, the effect of the initial tensile deformation is completely erased and the meaning of repeating the tensile deformation is lost. For this reason, the temperature was regulated to 300 ° C. or more and 950 ° C. or less.

Summarizing the above manufacturing process, a typical form for manufacturing a seam plate using the method of the present invention is as follows.
(1) As shown in the flowchart of FIG. 4, a columnar billet made of a shape memory alloy in a predetermined temperature region → hot extrusion (injection) → bend correction → solution treatment → tensile deformation → length cutting → bolt hole processing And how to.
(2) As shown in the flowchart of FIG. 5, a shape memory alloy billet in a predetermined temperature region → hot extrusion (injection) → bend correction → tensile deformation → length cutting → bolt hole processing to obtain a product.
In this case, training may be performed after the initial tensile deformation, or training may not be performed.
(3) A method in which a shape memory alloy columnar billet at a predetermined temperature → hot extrusion (injection) → tensile deformation → length cutting → bolt hole processing is made when bending correction is not required.

Next, more specific examples will be described.
(Example)
A columnar billet 1 made of a shape memory alloy containing 28% Mn, 6% Si, 5% Cr and the balance being Fe is used for a joint plate for a 73 kg class crane rail by hot extrusion with a columnar billet 1 having a length of 460 mm. A long steel 6a made of bar material was manufactured.
Since the cross-sectional shape of the long steel 6a after hot extrusion is a rough shape plus a finishing allowance of 2 mm for the cross-sectional shape of the seam plate product, the length of the long steel 6a after hot extrusion is long. The length was 6m (with crops on both ends).

Compression correction that compresses the long steel 6a so that it is pressed by the pressing member 30 from above while being supported as shown in FIG. 16 (b), and upper and lower correction rollers as shown in FIG. 16 (c). In addition to the roller straightening by 31, the tension straightening which gives about 3% plastic elongation by the bending straightening machine 8 as shown in FIG. 15 or the tension straightening machine comprising the hydraulic tension processing device 29 as shown in FIG. A straight long steel 6a was obtained, and solution heat treatment was performed in a furnace at 950 ° C. for 3 hours (the retention time at 950 ° C. was 1 hour) as shown in FIG.
After the solution heat treatment, the sheet was returned to the tension straightener again, both ends of the central portion of the length of 4.7 m were marked, and the length between the two marks was measured to be 4682 mm. Thereafter, the cropped portions at both ends are chucked, and the bend straightening machine 8 as shown in FIG. 15 or FIG. 16 (a) is used until the 4682 mm portion reaches 5.011 (7.03% as the value of strain). Tensile deformation was performed by a tension straightening machine comprising a hydraulic tension processing device 29 as shown. Although the above-described tensile deformation uses a bending straightener, it is not for bending correction, but a process necessary for operating the shape memory alloy joint plate so that the length is shortened when it is completed and heated, That is, it was performed to give a shape memory effect.

  As shown in FIG. 13A, the shape memory alloy joint plate 13 configured as described above is provided with a shape memory effect at the center in the longitudinal direction, as in the case of the conventional shape memory alloy rail joint plate 24. The fixing bolt long holes 14 and 15 are provided in the part, and the locking bolt holes 16 and 17 are provided at both ends in the longitudinal direction. The shape memory alloy joint plate 13 is arranged on both sides of the rails 18 and 19 adjacent to each other in series, and the shape memory alloy joint plate 13 is heated with the bolt 32 loosely joined. Thus, the shape is restored so as to be shortened from the dimension L1 to L2, and the rails 18 and 19 are brought into contact with each other so as to press each other. As shown in FIGS. Connect with no play.

  In the case of the present invention, since the rail joint plate is manufactured by a process including the hot extrusion method, it is possible to manufacture a joint plate having a different cross-sectional shape as appropriate by changing the extrusion die. Become more flexible.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing in the case of manufacturing the shape-memory alloy-made rail joint board for non-free connection of this invention, Comprising: (a) is the product made from a shape-memory alloy which is hot extrusion-injection-processed and has the length for several pieces Side view of the shape steel for rail joint plate, (b) is a state in which the shape memory alloy shape steel for rail joint plate having the length of a plurality of (a) is tensile-deformed to give a shape memory effect. (C) is a side view showing a state in which the shape steel of (b) is cut and cut to the length of one seam plate, and (d) is a bolt hole from the state of (c). It is a side view which shows the state drilled. (A) is a cross-sectional view of a shape memory for a shape joint made of a shape memory alloy for non-free connection after hot extrusion injection molding, (b) is a cross-sectional view after tensile deformation of the shape steel shown in (a) (C) is a cross-sectional view showing a cross-sectional form after tensile deformation including the training of the shaped steel shown in (a), (d) is a cross-sectional form shown in (a) and (b) It is sectional drawing shown repeatedly. It is explanatory drawing which shows the hot extrusion process of this invention. It is a figure which shows an example of the manufacturing process of the rail joint board made from the shape memory alloy for non-free connection of this invention with a flowchart. It is a figure which shows in a flowchart the other example of the manufacturing process of the shape seam alloy rail joint board for connection between no play of this invention. It is a figure which shows the rail joint board of a standard dimension on the left of a crane rail, and shows the cross-sectional form of the long shape steel after the hot extrusion molding by this invention on the right. It is a figure which shows the other example of the manufacturing process of the conventional shape memory alloy-made rail joint board for non-free connection with a flowchart. (A) is a side view showing a conventional shape memory alloy rail joint plate for non-playless connection, and (b) is a shape memory effect obtained by clamping both ends of a shape memory alloy member having a rectangular cross section by a conventional method. (C) is a side view showing a state in which both ends are cut from the state of (b) and bolt drilling is performed. The process in the case of manufacturing the conventional rail joint board made from a shape memory alloy is shown, Comprising: (a) is sectional drawing which shows the cross-sectional form of the member shown in FIG.8 (b), (b) is (a). It is sectional drawing which shows the state which gave rough cutting to the four surfaces of front and rear, right and left from the state of, and made it an octagonal cross section. It is a side view which shows the state which connected the crane rails with the shape memory alloy rail joint board for non-free connection. It is a top view of FIG. It is a front view of FIG. It is explanatory drawing which shows the process of connecting rails in a non-free space state using the rail joint board made from shape memory alloy for non-free connection. It is a top view which shows the connection part of the conventional rails. It is explanatory drawing which shows an example of a bending correction machine. (A) is a perspective view which shows the form in the case of giving a tensile deformation | transformation using a hydraulic tension processing apparatus, or carrying out tension correction, (b) is a perspective view which shows one form of compression correction, (c) is roller correction. It is a perspective view which shows one form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Columnar billet made from shape memory alloy 2 Heating furnace 3 Hot extrusion molding apparatus 4 Hydraulic extrusion tool 5 Die 6a Long shape steel 6b Long shape steel to which shape memory effect was provided 7 Rail joint board made from shape memory alloy 8 Bend straightening machine 9 Roll for traveling 10 Ring furnace 11 Wire rope 12 Winch 13 Rail joint plate with bolt hole made of shape memory alloy 14 Long hole for fixing bolt 15 Long hole for fixing bolt 16 Hole for locking bolt 17 Locking bolt Hole 18 Rail 19 Rail 20a Fixed position clamp (or chuck)
20b Position movable clamp (or chuck)
DESCRIPTION OF SYMBOLS 21 Hydraulic jack 22 Grasp part 23 Rail joint plate 24 Shape memory alloy rail joint plate 25 Bar material 26 with a rectangular cross section Engagement inclined upper surface 27 Engagement inclined lower surface 28 Cross section octagonal roughing rail joint plate 29 Hydraulic tension Processing device 30 Pressing member 31 Straightening roller 32 Bolt 33 Chucking tool 34 Holding frame

Claims (6)

In a manufacturing method of a shape memory alloy rail joint plate for connection between non-plays that is connected so as not to cause a gap between adjacent rails in series, an iron-based shape memory alloy material is heated at a temperature of 1050 ° C. to 1200 ° C. A long steel having a cross sectional shape slightly larger than the cross sectional shape of the rail joint plate made of shape memory alloy by the inter-extrusion method and having a length equal to or more than the length corresponding to a plurality of joint plates. After forming, the long deformation of the long steel was applied to the tensile deformation necessary to impart the shape memory effect at a temperature of 0 ° C. or higher and 50 ° C. or lower , and then the tensile deformation was applied. A method of manufacturing a rail joint plate made of shape memory alloy for connection between playless, characterized by cutting a section steel. After forming into a long steel having a length equal to or more than the length corresponding to a plurality of seam plates, the bending of the long steel is corrected by a tensile bending straightener, and then the long steel subjected to solution heat treatment at the state, then, claims, characterized in that to confer again back to tensile type straightening machine, by pulling said deformable tensioning straightening machine required to impart shape memory effect 2. A method of manufacturing a shape memory alloy rail joint plate for connection between no-plays according to 1.   After forming into a long steel having a length equal to or more than the length corresponding to a plurality of seam plates, the bending of the long steel is corrected by a tensile bending straightener, and then the long steel 2. The non-free connection for connecting abundantly according to claim 1, wherein a tensile deformation necessary for imparting a shape memory effect is imparted over substantially the entire length of the long steel without performing the solution heat treatment. A method of manufacturing a shape seam alloy rail joint plate.   2. The step of imparting tensile deformation necessary for imparting a shape recording effect is repeated twice or more with a heat treatment to a temperature range of 300 ° C. or higher and 950 ° C. or lower. Or the manufacturing method of the shape memory alloy-made rail joint board for non-free connection of 2.   5. The non-free connection according to claim 1, wherein the iron-based shape memory alloy material is an iron-based shape memory alloy mainly composed of Fe, Mn, and Si. A method of manufacturing a shape seam alloy rail joint plate.   5. The no-play connection according to claim 1, wherein the iron-based shape memory alloy material is an iron-based shape memory alloy mainly composed of Fe, Mn, Si, and Cr. Method of rail joint plate made of shape memory alloy for use.

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