JP6368636B2 - Seam welding method and heat exchanger manufacturing method using the same - Google Patents

Description

  The present invention relates to a seam welding method for a metal plate, and more particularly to a seam welding method for a metal plate constituting a panel heat exchanger and a method for manufacturing a panel heat exchanger using the same.

  Conventionally, for example, a seam welding method capable of ensuring airtightness has been employed for welding a metal plate constituting a panel heat exchanger. In this seam welding method, a metal plate in an overlapped state, which is an object to be welded, is sandwiched between a pair of disk-shaped electrode rollers, and an electrode roller that rotates and moves is energized while pressing the metal plate. In this method, the metal plates are welded to each other by the heat generated by the electrical resistance generated at the contact point between the metal plates when a current flows between the metal plates that are in close contact with each other. In this seam welding method, continuous linear welding is possible by rotating the electrode roller while pressing the metal plate.

  For example, Patent Document 1 discloses, as a conventional technique for seam welding of an overlapped portion of workpieces, “a welding method in which an overlapped portion of a first workpiece and a second workpiece is seam-welded, and the above-mentioned overlap is performed by a pair of roller electrodes. A DC or first frequency power is applied between the pair of roller electrodes across the mating portion to heat a predetermined region of the overlapping portion, and the first frequency between the pair of roller electrodes Discloses a method of welding a metal material in which the first workpiece and the second workpiece are welded by applying power of a second frequency different from each other and heating the peripheral region of the predetermined region.

JP 2010-274306 A

  A conventional welding apparatus that performs seam welding, such as Patent Document 1, includes a mechanism that presses and sandwiches a plurality of stacked metal plates with a pair of roller electrodes, and performs seam welding while rotating. When a panel-type heat exchanger is manufactured using such a welding apparatus, there is a problem that a heat medium or a refrigerant leaks from an end portion of the heat exchanger during use, and the heat exchanger is destroyed.

  As a result of intensive studies by the present inventors on this problem, the plurality of metal plates sandwiched between the roller electrodes are pressed at a constant pressure, and a predetermined current is passed through the plurality of metal plates with a constant power source to cause electrical resistance. Since welding is performed by heat, the roller electrode slides down in the pressing direction when passing through the end portions of the superimposed metal plates, and constitutes the workpiece 100 as shown in FIG. It has been clarified that the end portions of the metal plates 101 and 102 are thinned, and this is one factor causing leakage of the heat medium or refrigerant and destruction of the heat exchanger. Moreover, it became clear that the said thinning tends to occur as the thickness of the workpiece 100 increases.

  Then, this invention aims at providing the seam welding method which enables stable welding to the edge part of a metal plate, without producing thickness reduction, and the manufacturing method of a heat exchanger using the same. .

  In the seam welding method according to the present invention, the object to be welded in which a plurality of metal plates are laminated is pressed and sandwiched between a pair of roller electrodes, and the roller electrode is rotated while rotating on the surface of the object to be welded. It is a method of energizing between the electrodes to weld the object to be welded, and is substantially the same as each surface of both surfaces of the object to be welded at the edge of the object to be welded which is the end point of seam welding. It includes seam welding while fixing an auxiliary plate constituting a plane, and removing the auxiliary plate after seam welding.

  The method for manufacturing a panel heat exchanger according to the present invention is a method using the above-described seam welding method, wherein at least the first metal plate and the second metal plate are provided with protrusions forming a flow path for a heat medium or a refrigerant. The object to be welded is composed of the first metal plate and the second metal plate, and the auxiliary plate is used as an end point of seam welding. It includes fixing to the edge and performing seam welding, and removing the auxiliary plate after seam welding.

  According to the present invention, since the auxiliary plate is fixed to the edge of the object to be welded, when the roller electrode passes through the edge of the object to be welded that is the end point of seam welding, the thickness is reduced. This can be effectively prevented. Therefore, it is possible to reliably perform seam welding up to the edge of the workpiece to be welded that is the end point of the seam welding. Therefore, the leakage of the fluid injected into the weldment can be prevented, and the breakage of the weldment can be suppressed. In addition, it is possible to reduce work such as build-up on a portion where there is a high possibility of leakage of fluid to be injected into the weldment, and it is possible to efficiently manufacture a weldment such as a panel heat exchanger. Moreover, the panel type heat exchanger which does not have a problem in use can be provided.

It is a schematic diagram of the seam welding apparatus which enforces the seam welding method as embodiment of this invention. It is a perspective view which shows the state which is performing the seam welding in the state which fixed the auxiliary | assistant board to the edge part of the to-be-welded object. It is a top view which shows the state which fixed the auxiliary | assistant board to the 1st metal plate and 2nd metal plate which comprise a heat exchanger. It is a partial expanded side view of the heat exchanger of FIG. It is a top view of the heat exchanger after nozzle mounting which showed the seam welding location. It is explanatory drawing which shows the state of thickness reduction.

  Hereinafter, embodiments of the seam welding method of the present invention will be described by taking as an example a method using a seam welding apparatus suitable for performing the seam welding method. FIG. 1 is a schematic view of the seam welding apparatus S. The seam welding apparatus S includes a pair of roller electrodes including a first roller electrode 10 and a second roller electrode 20.

  The first roller electrode 10 and the second roller electrode 20 are made of a disk-shaped conductive material. 10 A of rotation surfaces of the 1st roller electrode 10 are arrange | positioned facing one surface (for example, upper surface) 31A of the to-be-welded object 30 which laminated | stacked the several metal plate. The rotating surface 20A of the second roller electrode 20 is disposed to face the other surface (for example, the lower surface) 32A of the workpiece 30 to be welded.

  The workpiece 30 is configured by, for example, stacking two metal plates 31 and 32 on top of each other. In the present invention, the metal plates 31 and 32 constituting the workpiece 30 are made of, for example, a material made of mild steel, titanium, aluminum or the like, or a material made of an alloy such as stainless steel or hastelloy. In addition, these metal plates may be comprised from the same material, and may be comprised from another material. There is no restriction | limiting in particular about each metal plate 31 and 32 about plate | board thickness. Therefore, each metal plate 31 and 32 may have the same plate thickness or different plate thicknesses.

  Further, the number of stacked metal plates constituting the workpiece 30 is not limited to the two described above, and may be three or more. Furthermore, in this invention, the to-be-welded object 30 is not limited to what overlaps the whole several metal plate, and is seam-welded, A some metal plate is partially overlapped, The said overlap was carried out. The part may be seam welded.

  The first roller electrode 10 described above is connected to a rotational drive motor 12 via a shaft 11. The second roller electrode 20 is connected to the rotational drive motor 22 via the shaft 21. Further, the first roller electrode 10 includes a control mechanism 13 that moves the first roller electrode 10 in a direction approaching or separating from the second roller electrode 20 that is disposed to face the first roller electrode 10 by adjusting the pressure. . Similarly, the second roller electrode 20 is provided with a control mechanism 23 that moves the second roller electrode 20 in a direction approaching or separating from the first roller electrode 10 disposed to face the second roller electrode 20 by adjusting the pressure. Prepare. By these control mechanisms 13 and 23, the workpiece 30 is pressed and held by the first roller electrode 10 and the second roller electrode 20. The configuration of the control mechanism is not limited to this, and one roller electrode is fixed, and the other roller electrode is moved in a direction approaching or separating from the one roller electrode. The welding object 30 may be pressed and held.

  A power supply 15 is connected to each of the first roller electrode 10 and the second roller electrode 20 via power supply lines 14 and 24, and a welding current is supplied between the pair of roller electrodes.

  The first roller electrode 10 and the second roller electrode 20 are formed on the surface 31A of the workpiece 30 and the surface 31A of the workpiece 30 by the rotation drive motors 12 and 22 in a state where the workpiece 30 is sandwiched by the control mechanisms 13 and 23 described above. It moves while rotating on the other surface 32A located on the opposite side. Further, by supplying a welding current between the roller electrodes 10 and 20, electrical resistance heat is generated at the contact points between the metal plates 31 and 32 constituting the workpiece 30, and the metal plates 31 and 32 are connected to each other. Weld.

  Next, specific steps of the seam welding method according to the present invention will be described. The seam welding method according to the present invention is, for example, a method of welding the workpiece 30 using the seam welding apparatus S described above, and the edge portion of the workpiece 30 serving as an end point of seam welding. 30A includes fixing the auxiliary plate 40 that is substantially flush with the surfaces 31A and 32A of the workpiece 30 and performing seam welding, and removing the auxiliary plate 40 after seam welding.

  As described above, when the auxiliary plate 40 is not fixed by fixing the auxiliary plate 40 to the edge portion 30A of the workpiece 30 that is the end point of the seam welding when the workpiece 30 is seam welded. The resulting meat loss can be suppressed. Therefore, the destruction of the panel heat exchanger can be prevented. In addition, since the said thickness reduction is easy to produce, so that the to-be-welded target object 30 is thick, it is effective with respect to the thing to which the to-be-welded target object 30 is thick.

  Here, the auxiliary plate 40 that forms substantially the same plane as both surfaces 31A and 32A of the workpiece 30 is the edge when seam welding is performed up to the edge portion 30A of the workpiece 30. It means the auxiliary plate 40 having a thickness that does not cause the thickness of the portion 30A to be reduced, and a thickness at which the seam welding of the edge portion 30A can be performed without any problem.

  Therefore, it is preferable that the auxiliary plate 40 is made of a plate material having substantially the same thickness as the workpiece 30 to be welded. In this way, by using the plate material having substantially the same thickness as the auxiliary plate 40, the edge portion 40 </ b> A of the auxiliary plate 40 is fixed to the edge portion 30 </ b> A of the workpiece 30 to be welded, so that the roller electrode 10. The first surface 31A and the other surface 32A of the workpiece 30 to be in contact with the 20 rotational surfaces 10A and 20A, and the first surface 40B and the other surface 40C of the auxiliary plate 40 are arranged on substantially the same plane. The In addition, since the end surface of the edge part 30A of the workpiece 30 is not necessarily flat, the end surface of the edge part 30A of the workpiece 30 and the end surface of the edge part 40A of the auxiliary plate 40 are brought into close contact with each other. In many cases, it cannot be fixed. Therefore, it is preferable to fix the edge part 30A of the workpiece 30 and the edge part 40A of the auxiliary plate 40 so that a gap is not generated as much as possible.

  Here, the auxiliary plate 40 having substantially the same thickness as the workpiece 30 is usually a thickness within a range of 0% to −10% with respect to the entire thickness of the workpiece 30. It is preferably in the range of 0% to -7%, particularly preferably in the range of 0% to -5%. The auxiliary plate 40 may be formed so that the thickness of the auxiliary plate 40 is thin within a range of up to 10% with respect to the entire thickness of the workpiece 30. The rotating surfaces 10A and 20A of the roller electrodes 10 and 20 that move on the surface of the plate 40 can move while applying a predetermined pressing force to the edge 30A of the workpiece 30 and perform seam welding without any trouble. Because it can.

  In addition, as shown in FIG. 1, the auxiliary plate 40 may be configured by overlapping a plurality (two in FIG. 1) of metal plates 41 and 42, as with the workpiece 30. A single metal plate may be used. At this time, the auxiliary plate 40 may be made of a material different from that of the metal plate constituting the workpiece 30 to be welded, but is made of the same material as each of the metal plates 31 and 32 constituting the workpiece 30 to be welded. More preferably. Thereby, fluctuations in the thickness of the workpiece 30 and the auxiliary plate 40 due to seam welding can be made constant, and the edge of the edge 30A of the workpiece 30 can be reduced without causing a reduction in thickness. This is because the seam welding of the portion 30A can be performed without any problem.

  Note that the edge 40A of the auxiliary plate 40 can be fixed to the edge 30A of the workpiece 30 by, for example, arc welding such as TIG welding or MIG welding. In addition to this, the edge portion 40A of the auxiliary plate 40 may be fixed to the edge portion 30A of the workpiece 30 by using a metal fitting such as a pin.

  Further, when the auxiliary plate 40 is configured by stacking a plurality of metal plates, each auxiliary plate metal plate constituting the auxiliary plate 40 is fixed to each metal plate constituting the workpiece 30 to be welded. Then, each metal plate constituting the workpiece 30 and each auxiliary plate metal plate constituting the auxiliary plate 40 may be overlapped and seam welded. Alternatively, seam welding may be performed after fixing the auxiliary plate 40 in a state where the metal plates for each auxiliary plate are overlapped to the workpiece 30 in a state where the respective metal plates are overlapped.

  Furthermore, the auxiliary plate 40 according to the present invention only needs to have an edge end portion 40 </ b> A that is fixed to the edge end portion 30 </ b> A side of the workpiece 30 to be welded, at least substantially the same thickness as the workpiece 30 to be welded. That is, the auxiliary plate 40 is configured in a tapered shape so as to be inclined downward from the side of the edge part 40A fixed to the workpiece 30 toward the edge part on the side opposite to the edge part 40A. May be. Thereby, the impact which arises when the roller electrodes 10 and 20 pass the edge part of the auxiliary | assistant board 40 can be relieved.

  In the seam welding method according to the present invention, the above-described auxiliary plate 40 is fixed to the object to be welded 30 and then the seam welding of the object to be welded 30 is performed using the seam welding apparatus S as described above. FIG. 2 shows a state in which the welding target 30 having the auxiliary plate 40 fixed to the edge 30A is being welded.

  By driving the rotation drive motors 12 and 22 with the roller electrodes 10 and 20 sandwiching the workpiece 30 to be welded, the roller electrode 10 rotates on the one surface 31A of the workpiece 30 and the roller electrode. 20 rotates on the other surface 32A of the workpiece 30 to be welded. The rotating surface 10A of the roller electrode 10 rotates without causing an impact when passing through the boundary surface from the one surface 31A of the workpiece 30 to the one surface 40B of the auxiliary plate 40. Similarly, the rotation surface 20A of the roller electrode 20 rotates without causing an impact when passing through the boundary surface from the other surface 32A of the workpiece 30 to the other surface 40C of the auxiliary plate 40. Therefore, the seam welding of the metal plate 31 and the metal plate 32 can be reliably performed with respect to the edge part 30A of the workpiece 30 that is the end point of the seam welding. In addition, if supply of the welding current between the roller electrodes 10 and 20 is performed at least immediately after the rotating surfaces 10A and 20A of the roller electrodes 10 and 20 exceed the boundary portion from the workpiece 30 to the auxiliary plate 40, Good. Then, after the seam welding is completed, the auxiliary plate 40 is removed from the workpiece 30 by cutting or the like.

  As described above in detail, according to the present invention, the object to be welded 30 in which the plurality of metal plates 31 and 32 are stacked is pressed and sandwiched between the pair of roller electrodes 10 and 20, and the roller electrodes 10 and 20 are inserted. The object 30 to be welded which is the end point of seam welding when the object 30 to be welded is seamed by energizing the roller electrodes 10 and 20 while rotating on the surfaces 31A and 32A of the object 30 to be welded. The seam welding is performed by fixing the auxiliary plate 40 that is substantially flush with the surfaces 31A and 32A of the both surfaces of the workpiece 30 to the edge portion 30A of the workpiece, so that the seam is not reduced. It is possible to reliably perform seam welding up to the edge of the workpiece to be welded that is the end point of welding. Therefore, the leakage of the fluid injected into the weldment can be prevented, and the breakage of the weldment can be suppressed. In addition, it is possible to reduce work such as build-up on a portion where leakage of fluid injected into the weld is likely to occur, and it is possible to efficiently manufacture welds such as panel heat exchangers.

  Next, a method for manufacturing a panel heat exchanger to which the seam welding method of the present invention is applied will be described. A method for manufacturing a panel heat exchanger to which the present invention is applied is a method for manufacturing a heat exchanger in which a flow path through which a heat medium or a refrigerant flows is formed between a first metal plate and a second metal plate. The above-described seam welding method according to the present invention is employed as a welding method between the first metal plate and the second metal plate.

  Hereinafter, a specific description will be given with reference to FIGS. 3 is a plan view showing a state in which the auxiliary plate 60 is fixed to the first metal plate 51 and the second metal plate 52 constituting the heat exchanger 50, and FIG. 4 is a partially enlarged side view of the heat exchanger 50 in FIG. FIG. 5 is a plan view of the heat exchanger 50 after the nozzle is mounted, showing the seam weld locations.

  The first metal plate 51 and the second metal plate 52 constituting the heat exchanger 50 are made of, for example, mild steel, titanium, as in the case of the metal plates 31 and 32 used for the configuration of the workpiece 30 in the seam welding method described above. It is made of a material made of aluminum, or a material made of an alloy such as stainless steel or hastelloy. At least one or both of the first metal plate 51 and the second metal plate 52 are formed with a convex portion 53 that forms a flow path 54 of a heat medium or refrigerant by pressing or the like. When only one of the first metal plate 51 and the second metal plate 52 is a flow path forming metal plate formed with a convex portion 53 that forms the flow path 54, the other may be a flat metal plate. Moreover, when both the first metal plate 51 and the second metal plate 52 are laminated and welded, a flow path forming metal plate formed with a convex portion 53 that forms the flow path 54 may be used. As shown in FIG. 4, in the heat exchanger 50 shown in the present embodiment, convex portions 53 that form flow paths 54 are formed on both the first metal plate 51 and the second metal plate 52.

  A flow path 54 is formed between the first metal plate 51 and the second metal plate 52 in a state where the first metal plate 51 and the second metal plate 52 are stacked and laminated. Is done. Both end portions 54A and 54A of the flow channel 54 are edge portions 50A of the heat exchanger 50 configured by overlapping the first metal plate 51 and the second metal plate 52 (also the edge portions of the laminate). .) And is formed to be open to the outside. One of the two end portions 54A and 54A of the flow path 54 forms an inlet for the heat medium or the refrigerant, and the other forms an outlet for the heat medium or the refrigerant. And nozzles 55 and 55 for connecting with the exterior are attached to these entrances and exits.

  When manufacturing the heat exchanger 50 mentioned above, first, the 1st metal plate 51 and the 2nd metal plate 52 are piled up, and a laminated body is formed. At this time, a flow path 54 is formed between the first metal plate 51 and the second metal plate 52. When the first metal plate 51 and the second metal plate 52 are overlapped and seam welded, in order to prevent them from shifting, the first metal plate is welded by arc welding or a fixture before the subsequent seam welding process is performed. The plate 51 and the second metal plate 52 are temporarily fixed and fixed. Examples of temporary fixing by arc welding include a method of temporarily fixing a plurality of locations by arc welding such as TIG welding and MIG welding. The temporary fixing method is not limited to this, and any temporary fixing method conventionally employed can be applied.

  Next, in the laminated body in which the first metal plate 51 and the second metal plate 52 are overlapped, the auxiliary plate 60 is attached to the edge end portion 50A serving as the end point of seam welding, that is, the portion to be seam welded to the edge end portion 50A. To fix. As described in the seam welding method, the auxiliary plate 60 fixes the edge portion 60A of the auxiliary plate 60 to the edge portion 50A of the laminate. The auxiliary plate 60 may be the same as that described in the seam welding method. The auxiliary plate 60 may be fixed after the first metal plate 51 and the second metal plate 52 are temporarily fixed, as in the seam welding method, or the first metal plate 51 and the second metal plate. You may perform with respect to the 1st metal plate 51 and the 2nd metal plate 52 before temporarily fixing 52. FIG. By fixing the auxiliary plate 60 to the edge portion 50A that is the end point of seam welding, the surface 51A of the first metal plate 51 that contacts the rotating surfaces 10A and 20A of the roller electrodes 10 and 20 of the seam welding apparatus S, and The front surface 52A of the second metal plate 52 and the one surface 60B and the other surface 60C of the auxiliary plate 60 are arranged in substantially the same plane.

  The auxiliary plate 60 may be fixed to the laminated body, for example, by arc welding as described in the seam welding method, but may be fixed using a metal fitting such as a pin.

  As described in the seam welding method, the auxiliary plate 60 may be constituted by a single metal plate, but the first metal plate 51 and the second metal plate 52 constituting the heat exchanger 50 shown in FIG. Each may be comprised from the same material, and may be comprised from a different material.

  After the auxiliary plate 60 is fixed to the laminate, seam welding of the first metal plate 51 and the second metal plate 52 constituting the laminate is performed. At this time, the seam welding is performed by rotating the roller electrodes 10 and 20 so as to border the flow path 54. As an example, the part which performs the seam welding of the said laminated body is shown by a thick line in FIG.

  Even when performing seam welding of the laminate, each of the surfaces 51A and 52A of the first metal plate 51 and the second metal plate 52 constituting the laminate is provided on the edge portion 50A serving as the end point of the seam welding. Auxiliary plate 60 constituting substantially the same plane is fixed.

  By driving the rotation drive motors 12 and 22 with the roller electrodes 10 and 20 sandwiching the laminate, the roller electrode 10 rotates on one surface 51A of the laminate, and the roller electrode 20 It rotates on the other surface 52A. The rotating surface 10A of the roller electrode 10 rotates without causing an impact when passing through a boundary surface from one surface 51A of the laminated body to the one surface 60B of the auxiliary plate 60. Similarly, the rotation surface 20A of the roller electrode 20 rotates without causing an impact when passing through the boundary surface from the other surface 52A of the laminated body to the other surface 60C of the auxiliary plate 60. Therefore, the seam welding of the 1st metal plate 51 and the 2nd metal plate 52 can be reliably performed with respect to the edge part 50A of the laminated body used as the end point of seam welding. The supply of the welding current between the roller electrodes 10 and 20 may be performed at least immediately after the rotating surfaces 10A and 20A of the roller electrodes 10 and 20 exceed the boundary portion from the laminate to the auxiliary plate 60.

  Then, after the seam welding as described above is completed, the auxiliary plate 60 is removed from the laminate by cutting or the like. Thereafter, the nozzle 55 is attached to the end 54A of the flow path 54 of the laminated body by, for example, a method such as welding to obtain the heat exchanger 50. At the time of attaching the nozzle 55, it is preferable to weld the portion where the seam welding of the end portion 54A of the flow path 54 is also performed with the welding to which the nozzle 55 is attached.

  As described above in detail, when a panel heat exchanger is manufactured using the seam welding method according to the present invention, a laminate formed by laminating the first metal plate 51 and the second metal plate 52. It is possible to reliably perform seam welding up to the edge of the laminate that is the end point of seam welding without causing a thickness reduction at the end 50A. Therefore, the leakage of the heat medium or refrigerant passing through the flow path 54 of the panel heat exchanger can be prevented, and the destruction of the panel heat exchanger can be suppressed. In addition, it is possible to reduce the work such as build-up on the portion where the leakage of the heat medium or refrigerant passing through the flow path 54 of the panel heat exchanger is likely to occur, and efficiently manufacture the panel heat exchanger. can do.

  The seam welding method according to the present invention enables seam welding to be reliably performed without causing a thickness reduction at an edge portion of an object to be welded. Therefore, the present invention provides an object to be welded such as a panel heat exchanger in which the end point of the seam welding is the edge of the object to be welded and the seam welding is required to be surely performed including that part. This is particularly useful when welding.

DESCRIPTION OF SYMBOLS S Seam welding apparatus 10 1st roller electrode 10A, 20A Rotating surface 11, 21 Shaft 12, 22 Rotation drive motor 13, 23 Control mechanism 14, 24 Feed line 15 Power supply 20 2nd roller electrode 30 Object to be welded 30A Edge 31, 32 Metal plate 31A One surface of the object to be welded 32A Other surface of the object to be welded 40, 60 Auxiliary plate 40A, 60A Edge 40B, 60B One surface of the auxiliary plate 40C, 60C Other surface of the auxiliary plate 41, 42, 61, 62 Metal plate 50 Heat exchanger 50A Edge portion 51 First metal plate 52 Second metal plate 53 Convex portion 54 Channel 54A End portion 55 Nozzle

Claims (2)

  An object to be welded on which a plurality of metal plates are laminated is pressed and sandwiched between a pair of roller electrodes, and the roller electrode is rotated on the surface of the object to be welded and energized between the roller electrodes. A method of welding an object, wherein an auxiliary plate that is substantially flush with each of both surfaces of the object to be welded is fixed to an edge of the object to be welded that is an end point of seam welding. Seam welding, and removing the auxiliary plate after seam welding. It is a manufacturing method of the panel type heat exchanger using the seam welding method of Claim 1,
Protrusions that form a flow path for a heat medium or a refrigerant are provided on at least one of the first metal plate and the second metal plate, or both, and the object to be welded includes the first metal plate and the second metal plate. Panel-type heat exchange comprising a metal plate, including fixing the auxiliary plate to an edge of the workpiece to be welded as an end point of seam welding, performing seam welding, and removing the auxiliary plate after seam welding Manufacturing method.

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