JP2003033814A - Production method of pipe with partition wall, production equipment and products thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in producing a pipe with a partition wall in a pipe axis direction inside a pipe, aim at a continuous production of a pipe with a partition wall of thin wall high strength structure made by monolithic forming of a thin wall lengthy steel strip, and produce a pipe with a partition wall having a high performance and durability with a high yield and productivity at a low cost. SOLUTION: In a pipe forming method that a pipe 1 with a partition wall 3 is formed by roll forming of a lengthy steel strip comprising the partition wall 3 in a pipe axis direction and a pipe outside circumferential portion 2 at one side and a pipe outside circumferential portion 2 at another side which are bent at the edges 5, 5 of the partition wall 3 respectively in the opposite directions, and also by welding weld zones 6, 6 of abutted portions between the edges 5, 5 of the partition wall 3 of the pipe 1 and the edges 4, 4 of the respective pipe outside circumferential portions 2, 2, a welding process part 21 is shielded in a shield box 22, and in an inert gas atmosphere where the inert gas is charged in the shield, a plurality of abutted portions between the edges 5, 5 of the partition wall 3 and the edges 4, 4 of the pipe outside circumferential portions 2 of the pipe 1 are welded simultaneously at the multiple points by the welding device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe having a partition wall in the pipe axial direction.

[0002]

2. Description of the Related Art Conventionally, a manifold having a partition wall in the tube axial direction such as a heat exchanger tube is formed by, for example, forming a steel strip into a tube by roll forming and cutting the tube into a proper length with a cutting machine. On the other hand, on the other hand, separately form a partition plate to be a partition in the axial direction of the pipe, press-fit the resulting partition plate into the pipe, and then form a partition by welding the partition plate and the pipe wall, for example, bending The manifold has the desired shape by processing. Alternatively, a steel strip is formed into an S-shaped cross section by roll forming, and the formed S-shaped end portions contact each other, and the central portion of the S-shape is defined as a partition wall portion in the pipe axis direction at both end portions of the partition wall portion. The manifold is formed by welding.

However, in the former molding method, there are many steps, and therefore, there is a problem that the manufacturing time is long and the cost is high, and furthermore, a long manifold cannot be formed. In the latter case, a long manifold can be integrally molded, but because of the shape of the bent projecting portion of the S-shaped joint, the welding work is more difficult than simple butt welding, and even if welding is possible, subsequent bending During processing, cracks in the welded part may cause poor yield,
Alternatively, there is a problem that the welded portion is cracked during use.

[0004]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to solve the above-mentioned problems in the conventional manufacturing and to provide a pipe having a partition wall of thin high strength structure by integrally molding a thin long steel strip. With the aim of continuous production, it is to produce tubes with excellent performance and durability at high yield, high productivity and low cost.

[0005]

Means for Solving the Problems The means for solving the above-mentioned problems is, in the invention of claim 1, the roll-formed long steel strip by a partition wall in the pipe axis direction and an end portion of the partition wall. Forming a tubular body having a partition wall from one pipe outer peripheral portion and the other pipe outer peripheral portion bent in opposite directions, and abutting the end portion of the partition wall of the tubular body and the end portion of each pipe outer peripheral portion. In a method of forming a tube having a partition wall by welding a portion, a welding step is shielded, and a plurality of tubular bodies are abutted by a welding device in an inert gas atmosphere in which the shield is filled with an inert gas. A method for manufacturing a pipe having a partition wall, which is characterized in that multiple parts are welded at the same time.

According to a second aspect of the present invention, the squeeze rolls provided at symmetrical positions on the outer periphery of the tubular body at the welding portion of the welding process portion are sandwiched to perform welding while ensuring the stability of the welding portion. It is a method for manufacturing a pipe having a partition according to claim 1.

According to the third aspect of the present invention, straightening rolls are arranged before and after the welding process portion so that the shape, straightness and twist of the tubular body before welding and the shape, straightness and twist of the pipe after welding are corrected by the straightening roll. The method for producing a pipe having a partition according to claim 1 or 2, characterized in that the pipe is straightened.

According to the invention of claim 4, the long steel strip is composed of a partition wall in the axial direction of the pipe and one outer peripheral portion of the pipe formed by bending the end portions of the partition wall in mutually opposite directions and the outer peripheral portion of the other pipe. A roll forming device for forming a tubular body having a partition wall, a pre-stage pinch roll arranged in the subsequent stage, and an abutting portion in which the end of the partition wall of the tubular body arranged in the subsequent stage and the end of the pipe outer peripheral portion are brought into contact with each other. In a manufacturing device of a pipe having a partition wall having a welding device for welding a pipe and a post-stage pinch roll for drawing out the pipe after welding placed in a subsequent stage, an inert gas is filled around the welding device to be inert. An apparatus for manufacturing a pipe having a partition wall, which is characterized in that a shield for providing a gas atmosphere is provided and a welding torch is arranged at a welding position of a pipe to be welded to form a welding device.

According to a fifth aspect of the present invention, a pair of squeeze rolls are symmetrically arranged at symmetrical positions of the pipe at the welded portion. is there.

According to the invention of claim 6, straightening rolls are provided between the front-stage pinch roll and the welding device and between the welding device and the rear-stage pinch roll, respectively. It is an apparatus for manufacturing a pipe having a partition wall.

According to a seventh aspect of the present invention, the pipe is manufactured by the method for manufacturing a pipe having a partition wall according to any one of the first to third aspects, and the inner wall of the pipe has a partition wall in the axial direction of the pipe. A tube having a partition, characterized in that the part is joined to the end of the partition.

Explaining the operation of the above means, firstly, by continuously performing forming and welding, the number of steps can be reduced to reduce the cost, and welding in an inert gas atmosphere can reduce welding burrs. The welding strength can be improved and the welding speed can be improved by simultaneously welding multiple points. Secondly, the welding can be performed while ensuring the stability of the welded portion. Third, it is possible to correct the shape, straightness, and twist of the tubular body before welding and the shape, straightness, and twist of the tube having the partition wall after welding, and further, as shown in FIG. It can be molded into a circular tube, or a tube whose outer shape is a square tube as shown in FIG. The obtained tube having a partition wall is thin, has high strength, and can be bent into various products, thus improving versatility. As described above, a pipe having a hollow portion by having a partition wall in the pipe axial direction by multi-point simultaneous welding at a plurality of points is cold-roll formed by a single stroke of a steel strip. It is possible to establish low cost methods and apparatus for continuous production from.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a view showing a shape of a pipe having a partition wall according to an embodiment of the present invention, taken along a plane perpendicular to the pipe axis direction. (A) is a circular pipe having an outer shape, and (b) is A rectangular tube having a rectangular outer shape is shown. FIG. 2 is a view of the welded portion according to the embodiment of the present invention as viewed in the flow direction of the process. FIG. 3 is a plan view of an apparatus according to an embodiment of the present invention, which extends from a pinch roll at a front stage to a squeeze roll at a welding portion through a straightening roll, and a straight roll at a subsequent stage to a pinch roll at a rear stage.
FIG. 4 is an elevational view of FIG.

The steps of one embodiment of the present invention will be schematically described. Long steel strip → Pipe forming into a tubular body having partition by cold roll forming → Straightening → Multiple points of contact of partition in axial direction of pipe. Simultaneous welding → straightening → cutting a pipe having a partition wall to a required length → finishing into a required shape (for example, bending) and finishing.

More specifically, a long steel strip is cold roll-formed by a conventional means, and is bent in opposite directions from the partition wall in the tube axis direction and both ends of this partition wall. A pipe having a partition wall of an external circular pipe or a pipe having a partition wall of an external circular pipe, which is bent from one bent pipe outer peripheral portion and the other pipe outer peripheral portion into an S-shape so as to be a tubular body having a partition wall. 11 By the above bending process, the S-shaped central portions of the tubes 1 and 11 are formed into partition walls 3 and 13 in the tube axial direction. The respective end portions 4, 4 or end portions 14, 14 of the pipe outer peripheral portions 2, 12 of the pipes 1, 11 are brought into contact with the end portions 5, 5 or 15, 15 of the partition walls 3, 13 in the pipe axial direction. At least the tubes 1, 11 are molded. Hereinafter, for convenience, the pipe 1 having a partition of an external circular pipe will be described. This tube 1
The pipe 1 having the partition wall is formed by welding the contacted portions of the end portion 4 of the partition wall 5 and the end portion 5 of the partition wall 5 as the welded portion 6. In this case, the welding process portion 21 of the welding process is housed in the shield box 22 for shielding, and the inert gas supply port 2 is provided in the shield composed of the shield box 22.
The argon gas is supplied and filled as an inert gas from 3 to make the inside of the shield an argon gas atmosphere. The pipe 1 of the work to be welded is fed into the shield in the argon gas atmosphere, and the welded portions 6, 6 in contact with the end portions 4, 4 of the pipe 1 and the end portions 5, 5 of the partition wall 3 are contacted with each other. Welding torch 26, 26 at the tip
As a result of the TIG welding apparatus equipped with a tungsten electrode rod as a pipe, the ends 5 and 5 of the partition wall of the pipe 1 and the ends 4 and 4 of the pipe outer periphery are provided.
The welded portions 6, 6, which are the contact portions, are simultaneously welded from the symmetric direction at multiple points.

In this case, the pipe 1 in the welding portion of the welding process is symmetrically positioned on the outer periphery of the pipe 1, and for the circular pipe shown in FIG. 2, the upper squeeze roll 24 and the lower squeeze roll 2 are used.
It is sandwiched by squeeze rolls arranged at the upper and lower symmetrical positions of 5, and welding is performed while ensuring stability so that the welded portion of the pipe 1 does not shift left and right. The squeeze roll has a larger diameter portion 28 on one side of the caliber 27 of the squeeze roll than the other in order to ensure the stability of the welded portion of the pipe 1 described above. On the contrary, on the opposite side, the large diameter portions 28, 28 are formed. From between the upper squeeze roll 24 and the lower squeeze roll 25, the tungsten electrode rods which are the welding torches 26, 26 face the welded portions 6, 6.

Further, as shown in FIG. 3, straightening rolls 29, 29 are arranged in front of and behind the welding process section 21 in the welding process, as shown in FIGS. 3 and 4. The pipe 1 is conveyed in the direction shown in the figure and passed through the straighteners 29, 29. The shape of the cold roll-formed external circular pipe 1 or external rectangular pipe 11 is determined or shaped by passing through the straightening roll 29 in the preceding stage as shown in FIG. 1 or the shape, straightness and twist of the tube 11 are corrected. Further, the shape, straightness, and twist of the pipe 1 or the pipe 11 after welding through the welding process portion 21 are corrected by passing the straightening roll 29 arranged at the subsequent stage of the welding process portion 21. The straightening roll 29 is composed of four rolls like a conventional means, and these are arranged in a square shape to form one group. In this case, the straightening rolls 29, 2
9 is the front pinch roll 30 after cold roll forming
And the welding device of the welding process unit 21, and between the welding device of the welding process unit 21 and the post-stage pinch roll 31.

[0018]

As described above, according to the present invention, as a pipe having a partition wall in the pipe axial direction, a pipe formed by cold roll forming is welded at multiple points in an atmosphere filled with an inert gas. By simultaneously welding, the welding time can be reduced, the weld burr can be reduced, the weldability is good, the weld strength is good, and the pipe with an excellent partition wall that does not cause cracks during bending of the product pipe after welding is yielded. It can be manufactured well at low cost, and the stability and reliability of welding are improved by arranging the squeeze roll in the welding process section. Furthermore, the pipe shape can be made flexible by arranging the straightening roll, and the straightness can be improved. The pipe with a bulkhead that is superior to the conventional ones, such as improving the weldability, making it possible to straighten the twist easily to enable continuous continuous manufacturing, and to weld even deep groove portions of the welded part. It can be produced.

[Brief description of drawings]

FIG. 1 is a view showing a shape of a pipe cut along a plane perpendicular to a pipe axis direction of an embodiment of the present invention, (a) is a circular pipe having an annular outer shape, and (b) is a square outer shape. It is a figure which shows the square tube of.

FIG. 2 is a view of the welded portion according to the embodiment of the present invention as viewed in the flow direction of the process.

FIG. 3 is a plan view of an apparatus according to an embodiment of the present invention, in which a pre-stage pinch roll passes through a straightening roll, a squeeze roll at a welded portion, a straightening roll at a subsequent stage, and a pinch roll at a subsequent stage.

FIG. 4 is an elevational view of FIG.

[Explanation of symbols]

1 tube 2 Pipe periphery 3 partitions 4 edges 5 edge 6 welds 11 tubes 12 Pipe periphery 13 partitions 14 Edge 15 edge 16 welds 21 Welding process section 22 Shield box 23 Inert gas supply port 24 Top Squeeze Roll 25 Lower squeeze roll 26 welding torch 27 Caliber 28 Large diameter part 29 Straightening roll 30 front stage pinch roll 31 Rear Pinch Roll

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 25, 2001 (2001.7.2)
5)

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

Further, as shown in FIG. 3, straightening rolls 29, 29 are arranged in front of and behind the welding process section 21 in the welding process, as shown in FIGS. 3 and 4. The pipe 1 is conveyed in the direction shown in the figure and passed through the straightening rolls 29, 29.
The shape of the cold roll-formed external circular pipe 1 or external rectangular pipe 11 is determined or shaped by passing through the straightening roll 29 in the preceding stage as shown in FIG. 1 or the shape, straightness and twist of the tube 11 are corrected. Further, the shape, straightness, and twist of the pipe 1 or the pipe 11 after welding through the welding process portion 21 are corrected by passing the straightening roll 29 arranged at the subsequent stage of the welding process portion 21. The straightening roll 29 is composed of four rolls like a conventional means, and these are arranged in a square shape to form one group. In this case, straightening roll 2
9 and 29 are arranged between the pre-stage pinch roll 30 after the cold roll forming and the welding device of the welding process part 21, and between the welding device of the welding process part 21 and the post-stage pinch roll 31. .

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tsutomu Anzaka             3-chome, Arahama-cho, Minami-ku, Nagoya             Industry Nagoya factory (72) Inventor Hidekazu Yamamoto             Chiba Prefecture Inba-gun Shisui-machi Ishino character Oyama new housework             Business Chiba factory F-term (reference) 4E028 BA04 CA02 CA14                 4E081 AA14 AA15 BA20 CA11 EA12                       EA39 EA41 EA45 YX07 YX13

Claims (7)

[Claims] 1. A tubular body having a partition wall formed by rolling a long steel strip by roll forming in the axial direction of the pipe and one outer peripheral portion of the pipe which is bent in opposite directions from an end portion of the partition wall and an outer peripheral portion of the other pipe. In the method of forming a body, and forming a pipe having a partition by welding the contact portion between the end of the partition of the tubular body and the end of the outer peripheral portion of each pipe, the welding process part is shielded, A method for manufacturing a pipe having a partition wall, wherein a plurality of abutting portions of a tubular body are simultaneously welded by a welding device in an inert gas atmosphere in which a shield is filled with an inert gas. 2. The welding according to claim 1, wherein the tubular body is sandwiched by squeeze rolls provided at symmetrical positions on the outer periphery of the tubular body at the welding portion of the welding process portion so as to stabilize the welding portion. A method of manufacturing a pipe having a partition wall. 3. A straightening roll is arranged before and after the welding process part to straighten the shape, straightness and twist of the tubular body before welding and the shape, straightness and twist of the tube after welding by the straightening roll. A method of manufacturing a pipe having a partition according to claim 1 or 2. 4. A tubular body having a partition wall formed by bending a long steel strip in the axial direction of the tube and bending one end of the partition wall in the other direction and the other outer peripheral portion of the tube. , A roll forming device for forming, a pre-stage pinch roll arranged in the subsequent stage, and a welding device for welding the abutting part in which the end of the partition wall and the end of the outer peripheral part of the tubular body in the subsequent stage are brought into contact with each other. And a pipe manufacturing apparatus having a partition wall having a post-stage pinch roll for withdrawing the post-welding pipe arranged in the subsequent stage, a shield for filling an inert gas atmosphere by filling an inert gas around the welding device And a welding torch provided at a welding position of a pipe to be welded to form a welding device. 5. An apparatus for manufacturing a pipe having a partition wall according to claim 4, wherein a pair of squeeze rolls are symmetrically arranged at symmetrical positions of the pipe at the welding site. 6. A pipe having a partition wall according to claim 4, wherein straightening rolls are provided between the front-stage pinch roll and the welding device and between the welding device and the rear-stage pinch roll, respectively. Manufacturing equipment. 7. A pipe manufactured by the method for manufacturing a pipe having a partition according to any one of claims 1 to 3, wherein the pipe has a partition in the axial direction of the pipe, and the outer peripheral end of the pipe is a partition end by welding. A tube having a bulkhead characterized by being joined to.