JP2005279684A - Welded metal pipe with flange and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a welded metal pipe with a flange in which a flange is integrally formed with a metal pipe by devising a metal pipe manufacturing process without joining the flange by welding or the like after the metal pipe is manufactured, and a method for manufacturing the same. The purpose is to provide metal pipes that can be hydroformed, allowing spot welding of hydroformed parts to other parts, and can be applied to general production lines equipped only with spot welding equipment. It is what.
In a welded metal pipe in which a seam of a metal pipe is overlapped and laser-welded, the metal pipe is arranged along the laser welded portion in the tube axis direction at one or two or more arbitrary positions in the circumferential direction of the metal pipe. A welded metal pipe with a flange, wherein the flange is an intermittent flange having a quadrangular or trapezoidal shape with respect to the pipe axis direction.
[Selection] Figure 2

Description

  TECHNICAL FIELD The present invention relates to a welded metal tube with a flange for hydroform applied to a component processed by hydroform applied to automobile parts, building materials, and the like, and a method for manufacturing the same. In addition, the present invention relates to a welded metal pipe with a flange that can be assembled by spot welding with other parts that are peripheral parts using a flange provided on the metal pipe, and a method for manufacturing the same.

For the purpose of reducing fuel consumption by reducing the weight of automobiles, reducing CO ₂ emissions, or improving collision safety for passenger protection, it is desired to reduce the thickness and strength of vehicle body structural members. As a solution for this need, the formation of steel pipes by the hydroforming method has begun to be adopted. In the hydroform method (hydraulic tube forming method), an inner pipe is placed in a split mold whose inner shape is the final product shape, and liquid is introduced from the end of the inner pipe into the inner pipe to apply internal pressure. This is a method in which a compressive load is applied in the direction of the tube axis from the end with a pushing cylinder and pushed into a final shape of the raw tube.

  By applying the hydroform method to metal pipes to make a predetermined part, it is possible to reduce the number of parts, reduce the weight of the parts, and integrally form and improve the accuracy of complex-shaped parts. Is possible.

  Previously, metal parts were press-formed and parts were constructed by spot or mash seam welding, so the spot or mash seam welding allowance could be used for integration with other parts. However, because hydroforming parts do not have welding costs, spot and mash seam welding cannot be used to join hydroformed parts to other parts, and conventional production lines with only spot and mash seam welding equipment will handle this. There was a problem that it was difficult to integrate with other parts. Therefore, when introducing a hydroform part, it was necessary to introduce an apparatus for welding a welding allowance for assembly to the part separately on the production line.

  For this reason, there has been proposed a joining method of hydroform parts and other parts that enables spot welding of hydroform parts and other parts, and is compatible with general production lines equipped only with spot welding equipment. (For example, refer to Patent Document 1).

  FIG. 1 is a view showing a conventional joining method between a hydroform component and another component. As shown in FIG. 1, in order to join the hydroform component 1 and the other component 2 by spot welding, the wall portion at a predetermined location in the hydroform component 2 is punched out in a partially connected state and bent outward. Joining is performed by spot welding 4 the formed flange 3 and the other component 2.

  However, in this method, since a part of the wall portion of the hydrofoam component is punched out, an opening is formed in the wall portion of the hydrofoam component, and there is a problem that the strength of the component is lowered.

  Moreover, there exists a flare processing method of a steel pipe edge part as a method of forming a flange, without welding to a steel pipe edge part (for example, refer patent document 2). In other words, the end of the steel pipe is fixed with a holder with a vertical surface formed on the entire surface with the flaring machining allowance portion, and a rotatable flare workpiece having a spherical surface on the head is used as the central axis of the steel pipe. Revolving and moving in a direction perpendicular to the central axis of the steel pipe, the flare work piece is pressed and moved outwardly from the base to be flared on the inner surface side of the lead portion of the steel pipe, This is a method of expanding the diameter of the lead-out portion of the steel pipe along the vertical front surface of the holder by the pressure movement.

  However, this method requires an apparatus for flaring and deforms and strains the steel pipe. And there exists a problem that a flange cannot be formed in the axial direction of a steel pipe.

Japanese Patent Laid-Open No. 11-170060 JP 52-146760 A

  The present invention provides a welded metal pipe with a flange in which a flange is integrally formed with a metal pipe and a method for producing the same by devising a metal pipe manufacturing process without joining the flange by welding or the like after the metal pipe is manufactured. Metal pipes can be hydroformed, and can be spot welded to hydroform parts and other parts, making it possible to handle general production lines that have only spot welding equipment. It is.

  The present inventor, when forming a metal plate blank for manufacturing a welded metal tube into a metal tube and performing laser welding, laser welds the blank formed with a flange width portion to be a flange, thereby providing a flange on the metal tube. As a result, the present invention was completed.

The gist of the present invention is as follows.
(1) In welded metal pipes that are laser welded by overlapping the joints of the metal pipes, the metal pipe and the metal pipe along the laser welded part in the pipe axis direction at one or more arbitrary positions in the circumferential direction of the metal pipe A flanged welded metal pipe having a flange formed integrally.

  (2) The welded metal pipe with a flange according to the above (1), wherein the flange is a square or trapezoidal intermittent flange with respect to the pipe axis direction.

  (3) A flanged welded metal tube having one or more rectangular or trapezoidal flanges integrally formed with the metal tube at an end of the metal tube.

  (4) The flanged welded metal pipe according to any one of the above (1) to (3), wherein the metal pipe is a metal pipe subjected to hydroforming.

  (5) The flanged welded metal pipe according to any one of (1) to (4) above, wherein the flange of the metal pipe and other parts are joined by spot welding or bolting.

  (6) While forming a metal plate blank cut wider than the width necessary for forming a metal tube into a tubular shape in which both ends are overlapped so that the flange width portion is outside the tube, or A method of manufacturing a metal tube with a flange, characterized in that after forming, a metal pipe is formed by laser welding the inside of the flange width portion of the overlapping portion, and then the flange width portion is formed to form a flange. .

  (7) The method for producing a flanged metal tube according to (6) above, wherein metal plates having different plate thicknesses and / or materials are butted and laser welded to form a metal plate blank.

  (8) At least one metal plate cut wide by the flange width dimension and the end of another metal plate are overlapped, and the inside of the flange width portion of the overlapped portion is laser welded to form a metal plate blank. The metal plate blank is molded into a tubular shape with both ends overlapped so that the flange width portion is on the outside of the tube, or after forming, the inside of the flange width portion of the overlapped portion is laser welded to form a metal tube. Then, a flanged metal pipe is produced by forming the flange width portion so as to raise the flange.

  (9) At least one metal plate cut wide by the flange width dimension and the end of another metal plate are overlapped, and the inside of the overlapped flange width portion is laser welded to form a metal plate blank. While forming both ends of the metal plate blank into a tubular shape so that the flange width portion is on the outside of the tube, or after forming, the butted portion is laser welded to form a metal tube, and then the flange width portion is raised. A method of manufacturing a flanged metal tube, wherein the flange is formed by forming the flange.

  (10) The flanged metal tube according to (8) or (9) above, wherein metal plates having different thickness or material are superimposed and laser welded to form a metal plate blank. Production method.

  (11) A plurality of flanges in which a metal plate blank is formed by overlapping end portions in the width direction of a plurality of metal plates and joining the insides of the flange width portions by laser welding in the respective overlapping portions. And a method for producing a flanged metal tube according to any one of (8) to (10) above, wherein the metal plate blank is made of a metal plate blank.

  (12) In any one of the above (6) to (11), the flange width shape at the end of the metal plate blank is an intermittent convex shape of one or two or more quadrangular or trapezoidal shapes. The manufacturing method of the metal pipe with a flange of description.

  (13) In any one of the above (6) to (12), the metal tube is processed into a part shape by hydroforming before forming the flange by forming the flange width portion so as to form the flange. The manufacturing method of the metal pipe with a flange of description.

  (14) At least one or two or more rectangular or trapezoidal convex portions are formed on one or both of the front end and rear end of the metal plate blank to be the front end and rear end of the metal tube, and the metal plate blank is A flanged metal tube formed into a tubular shape, or formed by welding a seam of a metal plate blank to form a metal tube, and then forming a flange so as to raise a convex portion Manufacturing method.

  (15) The method for producing a flanged metal tube according to any one of (6) to (14), wherein the metal plate is a plated steel plate.

  The welded metal pipe with flange according to the present invention is laser welded so that the seam of the metal pipe is overlapped and laser welded. Therefore, it can be applied to hydroforming, and the flange is formed by integral molding with the steel pipe body. Therefore, it is not necessary to weld the flange to the metal pipe, and it is possible to weld hydroform parts and other parts on a production line that has only general spot welding equipment, making it easy to incorporate hydroform parts. Become.

  Moreover, it can be set as the tailored metal pipe with a flange using the tailored blank metal plate which combined the metal plate from which one or both of board thickness and a material differ.

  Furthermore, it is possible to provide a welded metal pipe with a flange in which an arbitrary number of flanges are integrally formed with the metal pipe main body.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 2 is a view for explaining an embodiment of a flanged steel pipe manufactured from one steel plate blank of the present invention.

  As shown in FIG. 2 (a), a single steel sheet blank 6 having a thickness of 0.6 to 3 mm cut by a shear with a flange width dimension 5 wider than a width necessary for forming a steel pipe prepare. In order to form this steel plate blank 6 into a pipe, first, as shown in FIG. 2 (b), a lower die (die) 7 having a circular cross-sectional concave portion and an upper die (die) 8 having a circular cross-sectional convex portion. A steel plate blank is formed into a semicircular open tube 9 by a forming apparatus including:

  Next, as shown in FIG. 2 (c), the open tube formed by pressing is conveyed and restrained by a roll from the top, bottom, left and right by a mandrel 10 and a four-direction four-roll 11 at the center in a four-direction four-roll molding device. However, as shown in FIG. 2 (d), both end portions of the formed steel plate are formed into a circular tube 12, and the both ends of the formed steel plate are in an overlapped state 13 or in an overlapped state 13, as shown in FIG. A laser beam 15 is irradiated along the inside of the flange width 14 to be overlapped and laser welding 16 is performed to obtain a steel pipe 17. The steel pipe diameter is preferably in the range of 50 to 200 mm. The steel pipe is hydroformed as necessary to form a predetermined molded part. Then, as shown in FIG.2 (e), the flange 18 is formed by performing the shaping | molding process which raises the steel plate edge part used as a flange along a laser welding line, and it is set as the welded steel pipe 17 with a flange. The flange 18 is formed integrally with the steel pipe 17 main body. The hydroforming process is preferably performed before the flange is formed because the flange does not provide a processing resistance during the hydroforming process, but can also be performed after the flange is formed.

In addition, the width | variety required for setting it as a steel pipe means the sum total of the circumference of a steel pipe, and the required overlap allowance 19.
The manufactured welded steel pipe 17 with a flange can be spot-welded 4 with another component 6 and a flange 18 as shown in FIG. Also, bolting can be used instead of spot welding.

  FIG. 3 is a view for explaining an embodiment of a welded steel pipe with a flange manufactured from a steel plate blank obtained by superposing two steel plate end portions of the present invention and performing laser welding.

  As shown in FIG. 3A, the end portions of the two steel plates 20 and 21 are overlapped, and a laser beam 15 is irradiated along the inner side of the flange width 14 that becomes the flange of the end portions of the steel plates, thereby superposing the lasers. One steel plate blank is produced by welding 16. The two steel plates 20 and 21 used as blanks may be the same type of steel plate, but steel plates having different one or both of the plate thickness and material can be used, for example, the strength is partially required. In this case, different steel plates can be used in combination as required. When corrosion resistance is required, the steel plate may be a surface-treated steel plate such as a galvanized steel plate or an aluminum plated steel plate.

  As shown in FIG. 3B, the steel plate blank obtained by superposing the ends of the two steel plates 20 and 21 and laser welding first has a lower die 7 having a circular cross-sectional concave portion and a circular cross-sectional convex portion. A steel plate blank is formed into a semicircular open tube 9 by a forming apparatus having an upper die 8 having the upper die 8. Next, as shown in FIG. 3 (c), the circular tube 12 is formed by the central mandrel 10 and the four-way four rolls 11 using a four-way four-roll forming device. As shown in FIG. 3 (d), both ends of the steel sheet formed into a tubular shape are overlapped with each other in the overlapping state 13 or inside the flange width 14 serving as a flange at the end of the steel sheet. A laser beam 15 is radiated along, and laser welding 16 is performed to form a steel pipe 17. The steel pipe is hydroformed as necessary to form a predetermined molded part. Then, as shown in FIG.3 (e), the flange 18 is formed by performing the shaping | molding process which raises the steel plate edge part used as a flange along a laser welding part, and it is set as the welded steel pipe 17 with a flange. The flange 18 is formed integrally with the steel pipe 17 main body.

  In this example, it is shown that two flanges are formed on one steel plate 21, but it is also possible to form a flange on each of the steel plates 20, 21 as a steel plate blank.

  As shown in FIG. 2 and FIG. 3, as the flange shape of the flanged steel pipe according to the present invention, it has been described that one long flange is formed in the axial direction of the steel pipe. As shown in FIG. One or two or more intermittent square (rectangular) shapes or trapezoidal flanges 22 and 23 short in the axial direction of the steel pipe 17 may be used. Moreover, what is necessary is just to select the height of a flange arbitrarily, but it is preferable to set it in the range of 5 mm-20 mm. That is, if it is less than 5 mm, joining with other parts becomes difficult. On the other hand, if it exceeds 20 mm, it becomes unnecessarily large and hinders weight reduction. In order to obtain one or two or more intermittently shaped flanges, the shape of the flange width 14 portion serving as a flange at the end of the steel plate blank 6 is, for example, as shown in FIG. It can be manufactured by forming the concavo-convex shape in which the convex portion 25 is formed into the steel pipe 17. And the flanges 22 and 23 can be provided in the arbitrary positions in the axial direction of a steel pipe. By connecting the flange intermittently, if the flange is continuous when processing such as hydroform, it becomes difficult to process because it becomes a constraint at the time of processing, but by providing the flange only in the necessary part, processing becomes easy, Helps to reduce weight.

  In addition, since the flanged steel pipe is joined to other parts by spot welding, if it is necessary to provide a flange in accordance with the joining position of the other parts, one or more flanges are provided at any position in the circumferential direction. What is necessary is just to form.

  A case where a welded steel pipe having 1 to n pipe shaft longitudinal flanges at arbitrary positions in the circumferential direction is manufactured will be described.

As shown in FIG. 3 (e), when the plate thickness L is not changed in the circumferential direction as shown in FIG. Determined by the formula.
L = π (D−t) + n (Lf + Lk)
W = L / n
Here, D is the outer diameter, t is the thickness, Lf is the flange width, and Lk is the overlap allowance in laser welding. Further, when steel pipes are configured with different plate thicknesses in the circumferential direction, the overall control L and the control W of each steel plate to be configured are determined by the following equation as shown in FIG.
L = π (D−tave) + n (Lf + Lk)
W = L / n
tave, = Average (t1, t2,...)
Here, tave is a plate thickness average of each steel plate constituting.

  Equipment rows for manufacturing flanged steel pipes are shears for cutting steel sheets, tailored blank equipment for joining steel sheets, press equipment for forming joined steel sheets into open pipes, and roll trains that finally finish open pipes into steel pipes. And a laser welding device.

  Each steel plate is joined by lap joining by laser welding. When surface-treated steel sheets, such as galvanized steel sheets, are joined by laser welding, there is no place for surface-treated metals such as zinc evaporated by the laser to dissipate. Occurs. As a measure for preventing this phenomenon, as shown in FIG. A foil 26 of about 1 mm, for example, a synthetic resin tape with an adhesive, is applied to create a gap between the steel plates, whereby the evaporated surface-treated metal 27 is diffused 28 from the gap. As a result, the molten steel 29 is not scattered by the evaporation pressure.

The steel plates that have been joined are formed into an open tube by pressing. The shape of the die used for the press is shown in FIG. The basic curvature of the upper die (die) and the lower die (die) is determined by the following equation.
1 / ρl (curvature of upper die) = α × D / 2
1 / ρu (curvature of lower die) = β × (D−2t) / 2
Here, α and β are coefficients adjusted according to the material of the steel sheet, and D is the outer diameter.
The open pipe formed by pressing is lap-joined by laser welding while being transported and restrained by rolls from the top, bottom, left, and right to form a pipe.

  Next, the manufacturing method of the welded steel pipe with a flange which formed the flange in the edge part of a steel pipe is demonstrated.

  FIG. 7 is a view for explaining a method of manufacturing a flanged welded steel pipe in which a flange is formed at the end of the steel pipe. As shown in FIG. 7 (a), a rectangular or trapezoidal convex portion 30 is cut by a shear on one or both of the front end and the rear end of the steel plate blank 6 that is the end of the steel pipe. As shown in FIG. 7B, the blank is formed into a tubular shape, or a seam of the steel plate blank is formed by laser welding 31 while forming the steel pipe 17. Next, as shown in FIG. 7 (c), the flange 32 is formed by forming the raised portion so as to form a flanged steel pipe. The height of the flange can be selected arbitrarily, but if the flange width is too wide, it will be difficult to start up because the flange has a curved surface. Therefore, the flange width is the width within which the central angle of the cross section of the steel pipe is within 45 degrees. It is preferable to do. Since this steel pipe is provided with a flange at the end, as shown in FIG. 7 (d), it is possible to join the steel pipe and the other parts by spot welding 4 to the other parts 2 and the flange 32. It becomes. Moreover, the flanged steel pipe of this invention can form a flange in a steel pipe edge part, without performing a flare process conventionally.

  In the above description, a round steel pipe having a circular cross section has been described, but the cross section of the steel pipe may be a polygonal steel pipe such as a square or a rectangle.

  Although the steel pipe has been described above, the present invention can also be applied to metal pipes other than steel pipes that can be laser-welded and tailored blank materials. In the case of a metal tube using a tailored blank material, properties such as strength can be changed for an arbitrary portion of the metal tube. The tube shape is not limited to a round tube, and may be a square tube or the like.

It is a figure which shows the conventional joining method of a hydrofoam component and another component. It is a figure for demonstrating embodiment of this invention of the welded steel pipe with a flange manufactured from one sheet of steel. It is a figure for demonstrating embodiment of this invention of the welded steel pipe with a flange manufactured from the steel plate blank obtained by superposing the edge part of two steel plates, and carrying out laser welding. It is a figure which shows the shape of the steel plate flange for setting it as the welded steel pipe with a flange of 1 or 2 or more intermittent shapes, and a steel pipe. It is a figure which shows the example of the welded steel pipe with a flange in the case of comprising a steel pipe by the board thickness which differs in the circumferential direction. It is explanatory drawing in the case of carrying out the lap joining of the surface treatment steel plates like a galvanized steel plate by laser welding. It is a figure for demonstrating the welded steel pipe with a flange which formed the flange in the edge part of a steel pipe.

Explanation of symbols

1 Hydroform parts 2 Other parts 3 Flange 4 Spot welding 5 Flange width 6 Steel plate blank 7 Lower die (die)
8 Upper die (die)
9 Open tube 10 Mandrel 11 Roll 12 Circular tube 13 Overlapping state 14 Flange width 15 Laser beam 16 Laser welding 17 Steel tube 18 Flange 19 Overlay allowance 20 Steel plate 21 Steel plate 22 Flange 23 Flange 24 Convex portion 25 Concave portion 26 Foil 27 Evaporation Surface treated metal 28 Dissipated from voids 29 Molten steel 30 Convex part 31 Welding 32 Flange

Claims (15)

  In welded metal pipes that are laser welded by overlapping the joints of the metal pipes, they are integrally formed with the metal pipe along the laser welded part in the pipe axis direction at one or more locations in the circumferential direction of the metal pipe A welded metal pipe with a flange, characterized by having a flange.   The flanged welded metal pipe according to claim 1, wherein the flange is a square or trapezoidal intermittent flange with respect to the pipe axis direction.   A flanged welded metal pipe having one or more rectangular or trapezoidal flanges integrally formed with the metal pipe at the end of the metal pipe.   The welded metal pipe with a flange according to any one of claims 1 to 3, wherein the metal pipe is a metal pipe subjected to hydroforming.   The flanged welded metal pipe according to any one of claims 1 to 4, wherein the flange of the metal pipe and other parts are joined by spot welding or bolting.   After or after forming a metal plate blank that has been cut wider than the width required to make a metal tube into a tubular shape with both ends overlapped so that the flange width portion is outside the tube A method of manufacturing a flanged metal tube, wherein the inside of the flange width portion of the overlapping portion is laser welded to form a metal tube, and then the flange width portion is formed to form a flange.   7. The method of manufacturing a flanged metal pipe according to claim 6, wherein metal plates having different thicknesses or materials are abutted and laser welded to form a metal plate blank.   At least one metal plate that has been cut wide by the flange width dimension is overlapped with the other metal plate, and the inside of the flange width portion of the overlapped portion is laser welded to form a metal plate blank. While forming the blank into a tube with both ends overlapped so that the flange width portion is on the outside of the tube, or after forming, the inside of the flange width portion of the overlap portion is laser welded to form a metal tube, and then the flange A method of manufacturing a flanged metal tube, wherein a flange is formed by forming the width portion to rise.   At least one metal plate that has been cut wide by the flange width dimension is overlapped with the other metal plate, and the inside of the flange width portion of the overlapped portion is laser welded to form a metal plate blank. The blank is formed into a tubular shape with both ends butted so that the flange width portion is on the outside of the tube, or after forming, the butted portion is laser welded to form a metal tube, and then the flange width portion is raised. A method of manufacturing a flanged metal tube, comprising forming a flange by molding.   10. The method for manufacturing a flanged metal tube according to claim 8, wherein metal plates having different thickness or material are overlapped and laser welded to form a metal plate blank.   A metal plate blank forms a plurality of flanges in which end portions in the width direction of a plurality of metal plates are overlapped with each other, and the inside of the flange width portion is joined by laser welding at each overlapped portion. The method for producing a flanged metal tube according to any one of claims 8 to 10, wherein the metal plate blank is made of a metal plate blank.   The flanged metal tube according to any one of claims 6 to 11, wherein the flange width portion shape of the end portion of the metal plate blank is an intermittent convex shape of one or more quadrangular or trapezoidal shapes. Manufacturing method.   The flanged metal pipe according to any one of claims 6 to 12, wherein the metal pipe is processed into a part shape by hydroforming before forming the flange by forming the flange width portion to rise. Manufacturing method.   At least one or two or more rectangular or trapezoidal convex portions are formed on one or both of the front end and rear end of the metal plate blank to be the front end and rear end of the metal tube, and the metal plate blank is formed into a tubular shape A method for manufacturing a flanged metal tube, characterized in that a flange is formed by forming a metal pipe by welding a seam of a metal plate blank to form a metal pipe. . The method for manufacturing a flanged metal tube according to any one of claims 6 to 14, wherein the metal plate is a plated steel plate.

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