JP5121059B2 - Distortion removing apparatus and method - Google Patents

Description

  The present invention relates to a distortion removing apparatus and method for removing welding deformation caused when welding, and more particularly to a distortion removing apparatus and method using high-frequency induction heating.

  Many steel structures such as ships are assembled by welding steel plates. In general, welding of a steel plate is accompanied by welding deformation by drawing a peripheral portion when a welded portion heated to a high temperature cools. The removal of this welding deformation after welding is called “distortion removal”. Such a strain removing method includes a method using a mechanical means such as a press and a method using heating and cooling, which is also referred to as a wrinkle method. In a large structure such as a ship, it is difficult to employ mechanical means, and generally a method using heating and cooling is employed. Conventionally, an operator holds a gas torch in his / her hand and heats and cools while moving the front or back surface of the welded portion along the bead. For such work, the grasping of the heating state (heating temperature, heating depth, etc.) High skill is required in the cooling timing. Therefore, for example, a distortion removing device as described in Patent Document 1 and Patent Document 2 has been developed.

  Each of the strain relief devices described in Patent Literature 1 and Patent Literature 2 is a device that rapidly heats a welded portion by high-frequency induction heating and rapidly cools by water cooling. The strain relief device of Patent Literature 1 heats the floor surface. The trolley type, Patent Document 2 is a handy type that can heat a vertical wall surface. These distortion removing devices have effects such that a general worker who is not a skilled worker can maintain a constant quality and speed of the distortion removing work, and can improve the working environment of the worker.

Japanese Patent Laid-Open No. 11-170081 JP 2002-18521 A

  However, in the distortion removing devices described in Patent Document 1 and Patent Document 2, since only cooling water is poured when rapidly cooling the welded portion, problems such as poor cooling efficiency and easy cooling unevenness are caused. There is. Further, in the cart type distortion removing device described in Patent Document 1, since the heating mechanism is fixed to the cart, the distance between the welded portion and the heating unit is appropriately set when there is a curve or a step in the traveling portion of the cart. There is a problem in that heating unevenness occurs. Furthermore, in the handy type distortion removing device described in Patent Document 2, there is a demand to reduce the size and weight of the device.

  The present invention has been devised in view of the above-described problems, has excellent cooling performance, can appropriately maintain the distance between the welded portion and the heated portion, and can achieve downsizing and weight reduction of the apparatus. It is an object of the present invention to provide a distortion removing apparatus and method.

  According to the present invention, a heating unit having a heating coil that generates a heat source and a magnetic body disposed on the heating coil, a transformer unit that generates high-frequency magnetic flux in the heating coil, and a cooling fluid is discharged to the heating target unit And a cooling channel that includes a guide wall that surrounds the outer periphery of the heating unit and forms a cooling space between the heating unit and the heating target unit. The distortion removing device is provided in which the cooling flow path is disposed on the inner side, and a plurality of openings for discharging the cooling fluid radially are formed in the guide wall.

  When a plurality of the heating parts are arranged, it is preferable that the heating part having the guide wall is arranged so that the opening part communicates. The cooling flow path may be formed at a central portion of the heating unit, between the heating coil and the magnetic body, between the magnetic body and the guide wall, or in the heating coil. preferable. The transformer section may be immersed in insulating oil.

  The strain relief device may include a housing that houses the transformer unit, and the heating unit may be disposed on a distal end portion or a side surface of the distal end portion of the housing. Moreover, the said housing | casing may have the wheel which can move on the said heating object part, and the raising / lowering mechanism which makes the said heating part approach or separate from the said heating object part.

  Further, according to the present invention, there is provided a strain removing method for generating a high frequency magnetic flux in a heating coil to generate a heat source, removing the distortion caused by welding by performing heating by the heat source and cooling by a cooling fluid, A cooling space is formed surrounding the heating target part, the heating target part is heated by the heat source, the cooling fluid is discharged to the cooling space while heating is continued, and the cooling fluid is discharged from the cooling space. There is provided a distortion removing method characterized by cooling the heating target portion.

  The discharge of the cooling fluid may be started after a predetermined time has elapsed from the start of heating, and may be ended simultaneously with the end of cooling. The predetermined time is preferably set to a time before the temperature of the heating target portion reaches the target heating temperature, and the target heating temperature corresponds to 1/3 of the plate thickness of the heating target portion. It is preferable to set the temperature so that it can be heated to a depth.

  According to the above-described strain relief device and method of the present invention, the guide wall is formed in the heating unit, so that a cooling space in which the cooling fluid is retained can be formed. It is possible to effectively cool, improve the cooling efficiency, and suppress cooling unevenness. In addition, by surrounding the heating target portion with a surface, the distance between the heating target portion and the heating portion can be appropriately and stably maintained even when the heating target portion has irregularities such as undulations. .

  In the case where a plurality of heating parts having guide walls are arranged, the cooling fluid can be discharged from the openings even in the part where the guide walls are adjacent by arranging the openings so as to communicate with each other. Can be applied. In addition, by arranging a plurality of heating parts, a plurality of heating target parts such as both sides of the welded part can be heated and cooled by a single process, and the distortion removing operation can be made efficient.

  By forming the cooling flow path at a predetermined location inside the guide wall, the cooling fluid can be effectively discharged to the heating target portion. Further, by immersing the transformer part in the insulating oil, the parts in the transformer part can be arranged close to each other, and the entire apparatus can be reduced in size and weight. In particular, in a handy type strain relief device, by reducing the size and weight of the strain relief device, it is possible to reduce the burden on the worker and to cope with narrow places, and to improve work efficiency. be able to.

  Moreover, by cooling the heating target portion at a predetermined timing, the heating target portion can be cooled while being effectively heated, and the know-how of a skilled worker can be easily realized. In addition, in the distortion removing apparatus and method of the present invention, as in the case of the conventional distortion removing apparatus, a general worker who is not a skilled worker can maintain a constant quality and speed of the distortion removing work. There are effects such as improvement.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. Here, FIG. 1 is a figure which shows 1st embodiment of the distortion removal apparatus which concerns on this invention, (A) is a whole block diagram, (B) is a front enlarged view of a heating part. 2A and 2B are diagrams illustrating a state in which the cooling fluid is released, in which FIG. 2A is a cross-sectional view of the heating unit, and FIG. 2B is a front view of the heating unit.

  As shown in FIGS. 1 (A) and 1 (B), a distortion removing apparatus according to the present invention includes a heating unit 1 having a heating coil 1a that generates a heat source and a magnetic body 1b disposed in the heating coil 1a, and a heating coil. A transformer section 2 that generates a high-frequency magnetic flux in 1a, a cooling flow path 3 that discharges a cooling fluid to the heating target section X, and a cooling space that surrounds the outer periphery of the heating section 1 and between the heating section 1 and the heating target section X And a guide wall 4 that forms C, the cooling flow path 3 is disposed inside the guide wall 4, and the guide wall 4 has a plurality of openings 4a that discharge the cooling fluid. . In addition, although fluids, such as water, air, and liquid nitrogen, can be used for a cooling fluid, in the following description, the case where water is used as a cooling fluid is demonstrated.

  The strain relief device shown in FIG. 1A is a so-called handy type strain relief device. The transformer unit 2 is housed in a housing 5, and the heating unit 1 is disposed at the tip of the housing 5. ing. And the housing | casing 5 is comprised so that it may be connected and operated with the power supply device 6 arrange | positioned apart. Here, the power supply device 6 includes, for example, a high frequency power supply 61 that transmits power to the transformer unit 2, a cooling water tank 62 that stores cooling water of the transformer unit 2 and the high frequency power supply 61, and a pump that circulates the cooling water of the cooling water tank 62. 63, a control valve 64 that controls the discharge of the cooling flow path 3 of the heating unit 1, and a control unit 65 that controls the high-frequency power supply 61 and the control valve 64.

  The heating unit 1 includes a heating coil 1a and a magnetic body 1b, and this configuration is the same as that of a conventional strain relief device. The heating coil 1a has, for example, a substantially C-shape that is arranged so that the tip portion is substantially parallel to the heating target portion X, as shown in FIGS. 1 (B) and 2 (A). The open end portion is connected to a hanging portion 1c that extends toward the heating target portion X. When an alternating current is passed through the C-shaped portion of the heating coil 1a, an alternating magnetic field is generated. When the heating target part X, which is a conductor, is arranged in this alternating magnetic field, Joule heat is generated by the eddy current flowing in the heating target part X, and the heating target part X is heated. Accordingly, the heating coil 1a generates a non-contact heat source. The heating coil 1a is preferably made of, for example, a copper tube, and at least the C-shaped portion is preferably made of a square cross section. This is because the area facing the heating target portion X is increased. Of course, it is not limited to a square cross section, and may be circular or triangular. The magnetic body 1b is made of, for example, ferrite and has a function of concentrating the magnetic flux generated in the heating coil 1a to efficiently heat the heating target portion X. The magnetic body 1b is arrange | positioned so that the part other than the heating surface 1d which the heating coil 1a opposes the heating object part X may be covered. Here, the magnetic body 1b has a substantially circular shape that matches the shape of the heating coil 1a, and is formed with a notch 1e through which a portion corresponding to the hanging portion 1b is inserted. Note that a film of an electrical insulator such as ceramic may be formed on the heating surface 1d of the heating coil 1a, or may be formed in a spiral shape in which portions corresponding to a C-shape are wound in multiple layers.

  Here, FIG. 3 is a figure which shows the shape of the heating coil 1a, (A) is C-shaped, (B) is U-shaped, (C) is I-shaped. The C-shaped heating coil 1a shown in FIG. 3A is the heating coil 1a shown in FIGS. When the diameter r is increased, the C-shaped portion of the heating coil 1a is affected by thermal expansion over a wide range, and when the diameter r is decreased, the heating efficiency is deteriorated. Therefore, it is preferable that the heating portion (the shaded portion in the figure) be formed as small as possible within the range where the strain relief device is used. For example, in a welding distortion removing device used for a steel plate having a plate thickness of 8 mm or less, the diameter r is set to a size of 40 mm or less. The heating coil 1a may be formed in various shapes such as a U shape as shown in FIG. 3B, an I shape as shown in FIG. 3C, an elliptical shape, a polygonal shape, and the like. it can. The U-shaped heating coil 1a is effective when the width of the heating target portion X is wide, and the I-shaped heating coil 1a is effective when the width of the heating target portion X is narrow.

  The transformer unit 2 is a matching transformer for flowing a high-frequency current through the heating coil 1a, and includes a primary side winding, a secondary side winding, and the like, and is accommodated in a cooling jacket. A drooping portion 1 c of the heating coil 1 a is connected to the secondary side winding of the transformer unit 2. Since the configuration of the transformer unit 2 is the same as that of the conventional transformer unit, detailed description thereof is omitted here. In addition, as shown in FIG. 1A, a circulating cooling flow path 7 is connected to the transformer section 2 so that cooling water can be supplied into the cooling jacket. The circulating cooling flow path 7 is connected to the cooling water tank 62, the pump 63, the high frequency power supply 61, and the transformer unit 2, and is a flow path for circulating the cooling water. The transformer unit 2 is electrically connected to the high-frequency power supply 61 through the cable 8 and is connected to a rectifier circuit, a voltage control circuit, an inverter circuit, and the like.

  As shown in FIG. 1 (A), the cooling channel 3 has a leading end connected to the heating unit 1 and a trailing end connected to a cooling water supply source (for example, an industrial water channel supplied into the factory). In the middle, a control valve 64 is arranged. The control valve 64 is disposed in the power supply device 6, and the discharge of the cooling water from the cooling flow path 3 to the heating target part X is controlled by the action of the control unit 65. Further, as shown in FIGS. 1B and 2A, the tip of the cooling channel 3 is formed at the center of the heating unit 1. Specifically, the tip of the pipe line forming the cooling flow path 3 is fixed to the opening 1f formed at the center of the magnetic body 1b.

  As shown in FIG. 1B, the guide wall 4 has a cylindrical shape having a hollow portion 4c in which the heating unit 1 is disposed, and the guide wall 4 is attached to the housing 5 at the rear end portion. A mounting plate 4b for connection is formed in a flange shape. The mounting plate 4b may be formed so as to open the hollow portion 4c of the guide wall 4 as illustrated, or may be formed so as to close the hollow portion 4c. Further, as shown in FIG. 2A, the distal end of the guide wall 4 is disposed so as to protrude forward from the heating unit 1. Therefore, when the tip of the guide wall 4 is brought into contact with the heating target part X, the heating part 1 has a certain gap from the heating target part X. This gap is set according to conditions such as the material, size, shape, high-frequency current, maximum heating temperature, etc. of the heating coil 1a. A cooling space C is formed by the gap and the guide wall 4. Conventionally, since the gap between the heating part and the object to be heated is held at a point by the guide pins arranged around the heating part, when there are irregularities such as swells in the heating object part, The distance of the gap with the heating target portion differs depending on the place where the guide pin is pressed, and it was difficult to perform stable heating. However, in the present invention, the guide wall 4 is arranged to surround the heating target portion with a surface. Thereby, the clearance gap between a heating object part and a heating part can be hold | maintained appropriately and stably. The outer peripheral shape of the guide wall 4 is not limited to the illustrated circle, and may be a rectangle such as a triangle or a quadrangle, an ellipse, or the like, or along the shape of the heating coil 1a. The shape may be different.

  Furthermore, a plurality (six in this case) of openings 4a are equally arranged at the tip of the guide wall 4. The opening 4 a has, for example, a semicircular shape, a semielliptical shape, a rectangular shape, and the like, and discharges the cooling water discharged into the cooling space C radially to the outside of the guide wall 4. As shown in FIG. 2 (B), the openings 4a are uniformly formed in a part of the guide wall 4 that forms the cooling space C as described above, so that the cooling space C is discharged from the cooling flow path 3. The cooling water can be retained (see the hatched portion in the figure), the flow can be given to the cooling water (see the arrow in the figure), and the heating target part X can be efficiently and evenly cooled. In consideration of cooling efficiency, the openings 4a are preferably arranged evenly in about 3 to 8 locations, but they are not necessarily arranged radially, and may be arranged in 1 or 2 locations in the vertical direction. Further, the opening 4 a may be formed so as to cut out the tip end portion of the guide wall 4 or may be formed in an intermediate portion of the guide wall 4. Further, the tip of the guide wall 4 also has a function of stabilizing the position of the heating unit 1. Therefore, the guide wall 4 can be brought into contact with the surface having the heating target portion X with three or more legs by forming the opening 4a by cutting out three or more of the tip portions of the guide wall 4. The gap between the heating part 1 and the heating target part X can be stably maintained.

  The housing 5 is a component for separating the heating unit 1 from the power supply device 6 so that the heating unit 1 can be moved to an arbitrary heating target unit X. The housing 5 shown in FIG. 1A has a cylindrical shape extending in the horizontal direction, and the heating unit 1 is connected to the front surface of the tip. Further, the transformer unit 2 is disposed inside the housing 5, and a handle 5a is provided at the upper part. The heating unit 1 is connected to a cooling channel 3, and the transformer unit 2 is connected to a circulating cooling channel 7 and a cable 8. The illustrated case 5 is suitable for a case where an operator performs the distortion removal work by stabilizing the case 5 at the waist. Further, by holding the handle 5a with a spring balancer or the like and performing the work while guiding the housing 5 in a suspended state, the burden on the worker can be reduced. Although not shown, the casing 5 may be connected to a switch for signaling the start of the work for removing distortion. By disposing such a switch on the housing 5, it is possible for one worker to perform distortion removal work at an arbitrary position at an arbitrary timing.

  As described above, the power supply device 6 includes the high-frequency power supply 61, the cooling water tank 62, the pump 63, the control valve 64, the control unit 65, and the like. Since the high frequency power supply 61 and the cooling water tank 62 are heavy objects, they are configured separately from the housing 5. From the relationship of the lengths of the cooling flow path 3, the circulation cooling flow path 7, the cable 8, and the like, it is preferable to configure the power supply device 6 so that it can be transported near the work place. The control unit 65 transmits current from the high frequency power supply 61 to the transformer unit 2 at a predetermined timing, opens the control valve 64 at a predetermined timing, and discharges cooling water from the cooling flow path 3 to the heating target unit X.

  Here, FIG. 4 is an explanatory diagram of the distortion removing method of the present invention, where (A) is the relationship between time and the temperature of the heating target part X, and (B) is the thickness and heating depth of the heating target part X. Relationship. 4A, the horizontal axis indicates time (seconds), and the vertical axis indicates the temperature (° C.) of the heating target part X.

  The distortion removing method of the present invention generates a high-frequency magnetic flux in the heating coil 1a to generate a heat source (heating unit 1), performs heating by the heat source (heating unit 1) and cooling by cooling water, and causes distortion caused by welding. The cooling space C is formed by surrounding the heating target portion X, the heating target portion X is heated by the heat source (heating portion 1), and cooling water is supplied to the cooling space C while continuing the heating. It discharges, cooling water is discharged | emitted from the cooling space C, and the heating object part X is cooled. Specifically, the worker holds the casing 5 and presses the guide wall 4 against the heating target portion X, and in this state, the switch of the high frequency power supply 61 is turned on. When the high frequency power supply 61 is activated, a high frequency current flows to the heating coil 1a through the transformer unit 2, the heating unit 1 forms a heat source, and the heating target unit X is heated along the heating curve L in FIG. The The line of the heating curve L varies depending on the magnitude of the high-frequency current flowing through the heating coil 1a. The magnitude of the high-frequency current is determined by the relationship between the target heating temperature α and the plate thickness D. In order to effectively remove the distortion caused by welding, it is preferable to heat (fire) the steel sheet to a depth d that is 1/3 of the plate thickness D of the steel sheet. In the present invention, heating and cooling conditions are set as follows so that even a general worker can perform a distortion removing operation in the same manner as a skilled worker.

  First, the target heating temperature α is set in relation to the plate thickness D. The target heating temperature α is set empirically or statistically to a temperature that can be heated to a depth d by heating for several seconds. The depth d is set to a depth of 1/3 of the plate thickness D of the heating target part X as described above. Therefore, when the heating target portion X is heated without cooling, the target heating temperature α is reached at time t2, as shown in FIG. If cooling is performed after reaching the target heating temperature α, the temperature of the heating target portion X exceeds the target heating temperature α, and the depth d of the burning becomes too deep. Further, if the heating is stopped and cooled before reaching the target heating temperature α, the temperature of the heating target part X does not reach the target heating temperature α, and the firing depth d does not reach 1/3 of the plate thickness D. End up. Therefore, in the present invention, as shown in FIG. 4A, cooling is started from time t1 earlier than time t2 when the target heating temperature α is reached while heating is continued. That is, the cooling water is released after a predetermined time t1 has elapsed since the start of heating. And after continuing heating and cooling to time t3, heating and cooling are complete | finished in the order of heating-> cooling simultaneously or heating. By controlling heating and cooling in this way, the temperature of the heating target part X can be gradually made closer to the heating target temperature α, and the heating target part X can be sufficiently heated at a temperature close to the target heating temperature α. The firing depth d can be adjusted to be approximately 1/3 of the plate thickness D. For example, when the plate thickness of the heating target part X is 8 mm or less, the time t3 is set to 10 seconds or less, and the target heating temperature α is set to 1000 ° C. or less.

  Further, by using the strain relief device of the present invention shown in FIGS. 1 and 2, the cooling water is discharged from the cooling flow path 3 formed in the central portion of the heat source (heating portion 1) to the heating target portion X. Thereafter, the heating target portion X can be cooled by discharging radially from the opening 4 a of the guide wall 4. By adopting such a cooling method, the heating target portion X can be efficiently cooled so as not to cause uneven cooling, and the heating and cooling shown in FIG. 4A can be effectively performed. The heating and cooling described above are controlled by the control unit 65. Specifically, the control unit 65 controls ON / OFF of the high frequency power supply 61 and opening / closing of the control valve 64.

  Next, a modified example and other embodiments of the distortion removing device of the present invention will be described. Here, FIG. 5 is a cross-sectional view of the heating unit showing a modification of the cooling channel, (A) is the first modification, (B) is the second modification, (C) is the third modification, Is shown. FIG. 6 is a front view of the heating unit showing a state in which a plurality of heating units are arranged, in which (A) shows a two-point heating method and (B) shows a three-point heating method. FIG. 7 is an overall configuration diagram showing another embodiment of the strain relief device according to the present invention, in which (A) shows the second embodiment and (B) shows the third embodiment. In addition, in each figure, the same code | symbol is attached | subjected about the same component as the distortion removal apparatus of 1st embodiment shown in FIG.1 and FIG.2, and the overlapping description is abbreviate | omitted.

  In the first embodiment of the strain relief device described above, the case where the cooling flow path 3 is formed in the central portion of the heating unit 1 has been described, but the strain relief device of the present invention is not limited to such a configuration, The configurations shown in FIGS. 5A to 5C may be employed. In the first modification shown in FIG. 5A, the cooling flow path 3 is formed between the magnetic body 1b and the guide wall 4, and the second modification shown in FIG. 5B is a heating coil. The cooling flow path 3 is formed between 1a and the magnetic body 1b, and FIG. 5C shows the cooling flow path 3 formed in the heating coil 1a.

  In the first modification shown in FIG. 5A, the hollow portion 4c of the guide wall 4 is closed by the mounting plate 4b, the tip of the cooling flow path 3 is connected to the mounting plate 4b, and the mounting plate 4b and the guide wall 4 are connected. The heating unit 1 is disposed so as to leave a gap 31 for releasing cooling water to the cooling space C between the magnetic body 1b and the magnetic body 1b. Accordingly, the gap 31 also forms a part of the cooling flow path 3, and the cooling water discharged from the cooling flow path 3 passes through the gap 31 and supplies the cooling water to the heating target portion X from the outer periphery of the magnetic body 1 b. Can do. Even with such a configuration, the cooling space C can be filled with the cooling water discharged from the cooling flow path 3, the flow can be given to the cooling water, and the heating target portion X can be efficiently and evenly cooled.

  In the second modification shown in FIG. 5B, the hollow portion 4c of the guide wall 4 is closed by the mounting plate 4b, the concave portion 32 is formed in the central portion of the mounting plate 4b, and the tip of the cooling flow path 3 is formed in the concave portion 32. , A plurality of nozzles 33 communicating with the recess 32 are formed in the magnetic body 1b, and the magnetic body 1b is disposed on the heating coil 1a so as to form a gap 34 between the heating coil 1a and the magnetic body 1b. Is. Therefore, the recess 32, the nozzle 33 and the gap 34 also form a part of the cooling flow path 3, and the cooling water discharged from the cooling flow path 3 passes through the recess 32, the nozzle 33 and the gap 34, and the outer periphery of the heating coil 1a. The cooling water can be supplied to the heating target part X. Even with such a configuration, the cooling space C can be filled with the cooling water discharged from the cooling flow path 3, the flow can be given to the cooling water, and the heating target portion X can be efficiently and evenly cooled.

  In the third modification shown in FIG. 5C, a plurality of discharge holes are formed in the heating surface 1d of the heating coil 1a, and cooling water is supplied into the heating coil 1a. Therefore, the heating coil 1 a itself can form the cooling flow path 3 and supply cooling water to the heating target portion X. Even with such a configuration, the cooling space C can be filled with the cooling water discharged from the cooling flow path 3, the flow can be given to the cooling water, and the heating target portion X can be efficiently and evenly cooled.

  In the first embodiment of the strain relief device described above, the case of the one-point heating method in which the heating portion 1 that is a heat source is one for the housing 5 has been described, but the strain relief device of the present invention has such a configuration. The two-point heating method or the three-point heating method provided with a plurality of heat sources for the housing 5 may be adopted as shown in FIGS. 6 (A) and 6 (B). .

  The two-point heating method shown in FIG. 6 (A) is one in which two C-shaped portions are formed by one heating coil 1a so that two heat sources can be generated in one process. . Specifically, the heating coil 1a is arranged in such a manner that the open end portions of the C-shaped portion face each other, the hanging portion 1c is connected to one open end portion, and the other open end portions are connected by a connecting portion 1g. I am doing. And the magnetic body 1b is arrange | positioned in each C-shaped part of the heating coil 1a, and the two heating parts 1 are formed. In this way, by arranging a plurality of heating parts 1, a plurality of heating target parts X such as both sides of the welded part can be heated and cooled by a single process, and the distortion removal work can be made efficient. it can. Each heating unit 1 is provided with a guide wall 4. At this time, the guide walls 4 are arranged such that the openings 4a communicate with each other. By arranging the guide wall 4 in this way, the cooling water can be discharged radially even at a portion where the guide wall 4 is adjacent, and uniform cooling can be performed.

  The three-point heating method shown in FIG. 6 (B) is one in which three C-shaped portions are formed by one heating coil 1a so that three heat sources can be generated in one process. . Specifically, the heating coil 1a is arranged with the open ends of the C-shaped portions facing each other, the drooping portion 1c is connected to one open end, and the two open ends are connected to each other by a connecting portion 1g. The shape is made. And the magnetic body 1b is arrange | positioned in each C-shaped part of the heating coil 1a, and the three heating parts 1 are formed. In this way, by arranging a plurality of heating parts 1, a plurality of heating target parts X such as both sides of the welded part can be heated and cooled by a single process, and the distortion removal work can be made efficient. it can. Each heating unit 1 is provided with a guide wall 4. At this time, the guide walls 4 are arranged such that the openings 4a communicate with each other. By arranging the guide wall 4 in this way, the cooling water can be discharged radially even at a portion where the guide wall 4 is adjacent, and uniform cooling can be performed.

  Note that the shape of the heating coil 1a is not limited to the one using the illustrated C-shape, and a plurality of heating units 1 may be formed using the U-shape or I-shape shown in FIG. Alternatively, the heating coil 1a of each heating unit 1 may be formed in a plurality of turns. Moreover, you may make it surround the some heating part 1 with the one guide wall 4. FIG.

  In the first embodiment of the strain relief device described above, the case 5 is a handy type, but the strain relief device of the present invention is not limited to such a configuration, and FIGS. As shown in (3), it can also be applied to other types of handy type and trolley type distortion removing devices.

  The second embodiment of the strain relief device shown in FIG. 7A is a handy type strain relief device in which the heating unit 1 is disposed on the side surface of the front end of the housing 5. Here, the heating unit 1 is disposed on the side surface of the tip of the protruding portion 5 b connected to the housing 5. With this configuration, even when the heating target part X is at a high position or a narrow place, the heating part 1 can be arranged on the heating target part X to perform the distortion removing operation. Here, the case where the transformer unit 2 is immersed in insulating oil is illustrated, and components in the transformer unit 2 are arranged close to each other to reduce the size and weight of the entire apparatus. In this case, since the cooling water cannot be supplied into the transformer unit 2, the transformer unit 2 is accommodated in the cooling jacket and the cooling water is supplied into the cooling jacket. In the figure, the case 5 itself is shown as a cooling jacket. Note that the configuration in which the transformer unit 2 is immersed in insulating oil is not limited to the second embodiment, and can be applied to the first embodiment described above and the third embodiment described later to reduce the size of the apparatus. In addition, the weight can be reduced.

  The third embodiment of the strain relief device shown in FIG. 7B is a cart type strain relief device in which the housing 5 is configured to be movable on the heating target portion X. Specifically, the housing 5 includes a wheel 5c that can move on the heating target part X, and an elevating mechanism 5d that moves the heating part 1 close to or away from the heating target part X. The elevating mechanism 5d may use an actuator mechanism or may use a spring biasing force. When an actuator mechanism is used for the elevating mechanism 5d, the actuator is stopped when it is detected by a pressure sensor or the like that the heating unit 1 is in contact with the heating target unit X, and the heating unit 1 is raised when the distortion removing operation is completed. It is preferable to configure. In addition, when a spring biasing force is used for the elevating mechanism 5d, it is preferable that the spring biasing force works so as to always press the heating unit 1 against the heating target portion X. During movement, a slippery member may be placed on the contact surface of the heating unit 1 (guide wall 4) and slid on the steel plate, or the heating unit 1 may be manually fixed at a position away from the steel plate. It may be.

  The present invention is not limited to the above-described embodiment. For example, the modification of the cooling flow path 3 shown in FIGS. 5A to 5C is also applied to the strain relief apparatuses of the second embodiment and the third embodiment. Of course, various modifications can be made without departing from the spirit of the present invention.

It is a figure which shows 1st embodiment of the distortion removal apparatus which concerns on this invention, (A) is a whole block diagram, (B) is a front enlarged view of a heating part. It is a figure which shows the state which discharge | released the cooling fluid, (A) is sectional drawing of a heating part, (B) is a front view of a heating part. It is a figure which shows the shape of a heating coil, (A) is C-shaped, (B) is U-shaped, (C) is I-shaped. It is explanatory drawing of the distortion removal method of this invention, (A) shows the relationship between time and the temperature of a heating object part, (B) has shown the relationship between the plate | board thickness of a heating object part, and a heating depth. It is sectional drawing of the heating part which shows the modification of a cooling channel, (A) shows the 1st modification, (B) shows the 2nd modification, (C) has shown the 3rd modification. It is a front view of the heating part which shows the state which has arrange | positioned the several heating part, (A) has shown the structure of 2 point | piece heating and (B) has 3 point | piece heating. It is a whole block diagram which shows other embodiment of the distortion removal apparatus which concerns on this invention, (A) is 2nd embodiment, (B) has shown 3rd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heating part 1a Heating coil 1b Magnetic body 1c Hanging part 1d Heating surface 1e Notch part 1f Opening part 1g Connection part 2 Transformer part 3 Cooling flow path 4 Guide wall 4a Opening part 4b Mounting plate 4c Opening part 5 Case 5a Handle 5b Projection 5c Wheel 5d Elevating mechanism 6 Power supply 7 Circulating cooling flow path 8 Cable 31 Clearance 32 Recess 33 Nozzle 34 Clearance 61 High frequency power supply 62 Cooling water tank 63 Pump 64 Control valve 65 Control part

Claims (10)

A heating unit having a heating coil that generates a heat source and a magnetic body disposed on the heating coil, a transformer unit that generates a high-frequency magnetic flux in the heating coil, a cooling channel that discharges a cooling fluid to the heating target unit, A strain relief device comprising:
A guide wall that surrounds the outer periphery of the heating unit and forms a cooling space between the heating unit and the heating target unit, the cooling flow path is disposed inside the guide wall, and the guide wall Has a plurality of openings through which the cooling fluid is discharged.   The distortion removing apparatus according to claim 1, wherein a plurality of heating units having the guide walls are arranged so that the openings communicate with each other.   The cooling flow path is formed in a central part of the heating unit, between the heating coil and the magnetic body, between the magnetic body and the guide wall, or in the heating coil. The distortion removing apparatus according to claim 1.   The distortion removing apparatus according to claim 1, wherein the transformer unit is immersed in insulating oil.   The distortion removing apparatus according to claim 1, further comprising a housing that houses the transformer unit, wherein the heating unit is disposed on a front end portion or a side surface of the front end portion of the housing.   The distortion removing apparatus according to claim 5, wherein the housing includes a wheel that is movable on the heating target unit, and an elevating mechanism that moves the heating unit closer to or away from the heating target unit. . A distortion removing method for generating a high-frequency magnetic flux in a heating coil to generate a heat source, and performing heating by the heat source and cooling by a cooling fluid to remove distortion caused by welding,
A cooling space is formed surrounding the heating target part, the heating target part is heated by the heat source, the cooling fluid is discharged to the cooling space while heating is continued, and the cooling fluid is discharged from the cooling space. The distortion removing method, wherein the heating target part is cooled.   The distortion removing method according to claim 7, wherein the discharge of the cooling fluid is started after a predetermined time has elapsed from the start of heating and is ended simultaneously with the end of cooling.   The distortion removing method according to claim 8, wherein the predetermined time is set to a time before the temperature of the heating target portion reaches a target heating temperature. The distortion removal method according to claim 9, wherein the target heating temperature is set to a temperature at which the target heating temperature can be heated to a depth corresponding to 1/3 of the plate thickness of the heating target portion.