JP2000102820A - Manufacture of specially shaped pipe having wall, cross section of which is incurvated in convexo-concave shape around central axis - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a specially shaped pipe having a wall, cross section of which is incurvated in a convexo-concave shape around a central axis. SOLUTION: This method is to weld the end faces of longitudinal direction of a plate material in which plural identical angular or corrugated shapes in cross-section are formed in the longitudinal direction to obtain a pipe element in which the cross-section meeting a pipe axis at right angles is convexo- concave, and to reduce a distance between respective tip ends of the parts convexed toward the inside of the pipe by a die and/or forming roll to form a pipe wall wherein the cross-section perpendicular to the pipe axis direction is incurvated like pleat. According to this method, manufacturing of a specially shaped pipe 6 can easily be carried out, a tool is hard to abrade and dimentional accuracy is also improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a deformed pipe, and more particularly, to an economical method for manufacturing a deformed pipe having a pipe wall whose cross section perpendicular to the pipe axis direction is folded.

[0002]

2. Description of the Related Art Conventionally, the production of a cross-sectionally deformed pipe having a folded pipe wall has already been put to practical use, for example, as a heat exchanger pipe (for example, Japanese Patent Application Laid-Open Nos. 4-258319 and 5-7965, JP-A-6-15354,
See JP-A-7-24521 and JP-A-7-24522). And these products are performing quite well.

[0003]

However, at present, satisfactory characteristics are not always obtained in the above-mentioned conventional shaped tubes, and further improvements are desired in the manufacturing process. I was

An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide a method of manufacturing a deformed tube which is easy to manufacture, has high strength, and has excellent heat exchange characteristics.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies and as a result, as a raw material for forming a deformed pipe, a plate (band) material before forming a pipe is formed with irregularities. It is effective to form the tube afterwards, or to draw out the metal tube using a grooved die and a grooved floating plug, and to reduce the heat exchange by reducing the diameter of the deformed tube. The inventors have found that the characteristics are improved, and have completed the present invention.

The present invention has been made based on the above findings,
A longitudinally end surface of a plate material in which a plurality of cross-section stars or waveforms having the same shape are formed in the longitudinal direction is joined to form a tubular body whose cross section perpendicular to the tubular axis is uneven, and the tubular body is formed by a die and / or a forming roll. The gist of the present invention is a method for manufacturing a deformed pipe, characterized in that a cross section perpendicular to the pipe axis direction is formed on a pipe wall curved in a fold shape by reducing the distance between the tips of the convex portions toward the inside of the pipe.

Further, the present invention provides a method for forming a plurality of concaves and convexes having the same shape in a tube perpendicular direction by using a grooved die and a grooved floating plug to draw a metal tube. A method for producing a deformed pipe, wherein a section perpendicular to the pipe axis direction is formed into a fold-like curved pipe wall by drawing the pipe to reduce the distance between the tips of the convex portions toward the inside of the pipe. It is the gist.

[0008] Further, the gist of the present invention is to produce a long deformed tube by using a continuous long strip, and using a tube or plate having a plating layer formed on the surface, It is also the gist of the present invention that the plating layer is reflowed by heating after forming the deformed pipe.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction and operation of the present invention will be described.
In the present invention, as a raw material for forming a deformed portion of a pipe, a plurality of cross-sectional waveforms 2 having the same shape are formed in a longitudinal direction by a forming roll as shown in FIG. 2 as shown in FIG. By joining the longitudinal end surfaces 4 and 5 of the plate material 1,
As shown in FIG. 1 (b), a cross section perpendicular to the pipe axis is formed into a deformed pipe 6 having irregularities. The forming roll in FIG. 2 is a combination roll, and by replacing the convex roll element 3 having a cross-sectional shape formed on the tube material, it is possible to form an arbitrary corrugation and a rectangular irregularity on the tube material.

Next, when the distance between the tips of the concave portions of the tube body 6 is reduced by a die and / or a forming roll,
The rectangular shape or the waveform is as shown in FIG. 3B, and becomes a deformed tube having a large wall area with respect to the cross-sectional area in the tube.

In the method of manufacturing a modified pipe according to the present invention using a grooved die and a grooved floating plug in combination, a grooved die 16 and a grooved floating plug 17 shown in FIGS. 6 and 7 are used. As a base tube, depending on the shape of the desired deformed tube,
Select a metal pipe with a specified thickness and pipe diameter. When a die is drawn using a floating plug for the material pipe, the pipe becomes thinner and thinner. Therefore, a raw pipe thicker than the thickness of the target deformed pipe is selected.

In the present invention, it is possible to manufacture a deformed pipe having an arbitrary length by manufacturing a raw pipe (inner pipe) using a long strip. As shown in FIG. 4, a long inner pipe 11 (an inner pipe that is being manufactured by combining the formation of concavities and convexities with a roll of FIG. 2 continuously from a long strip and the deformed pipe manufacturing process of FIG. 1) may be used. 5) by using a long strip 12a for the outer pipe 12 formed by welding with a welding torch 13 so as to enclose the inner pipe and reducing the diameter of the outer pipe 12 with a die 14. It is possible to manufacture a deformed pipe having a double pipe structure of such an arbitrary length.

In the present invention, in addition to a fixed length tube, in order to manufacture a long, irregularly shaped tube with good yield at low cost,
A coil tube wound in a coil shape, a so-called PIC (PIC
EIN COIL) is continuously drawn while being unwound.

In order to pull out the tube by the die 16 or 19 using the floating plug 17 or 18, a plug with a groove is inserted into the tube from the end of the tube, the end of the tube 20 is squeezed to a small diameter, and the small diameter portion is squeezed. Initiate drawing through the hole in the grooved die. In the floating plug pulling, the setting of the die and the plug is not fixed, so that the plug is automatically set at the time of pulling out, and the setting according to the shape of pulling out the die and the plug becomes unnecessary, so that the working time can be reduced.

When the floating plug drawing is started, the grooved plug 17 of FIG. 7 is drawn into the hole 16a of the grooved die 16 of FIG. Grooved plug 1
7, a gap portion having an uneven shape is formed in a direction perpendicular to the tube axis, and the raw tube 20 that has passed through the gap portion is formed into a deformed tube 6. If the drawing process is performed by floating plug pulling, 1
The outer periphery of the metal tube has substantially the same shape and size as the surface of the grooved die, and the inner periphery has substantially the same shape and size as the surface shape of the grooved plug. next,
When the distance between the tips of the concave portions of the deformed tubular body 6 is reduced by a die and / or a forming roll, the square or the waveform becomes as shown in FIG. The deformed pipe 6 has a large pipe wall area.

[0016]

Since the present invention is constructed as described above, the shape, size and number of folds of the deformed pipe are determined by the width of the plate material of the raw tube material and the shape and number of irregularities formed or used. Since it is determined by the floating plugs combined with the number of grooves in the die, it is possible to easily manufacture deformed pipes, and it has excellent effects such as less tool wear and high finished dimensional accuracy. Extremely useful.

[0017]

EXAMPLES The present invention will be described specifically with reference to Examples.
This does not limit the invention. Example 1 For a 47 mm wide and 0.8 mm thick strip (material SPCC), four corrugations with a cross section in the width direction of 3 mm were formed by corrugated rolls, and the side edges of the corrugated rolls were resistance-welded to a maximum diameter of 1 mm.
A 2 mm deformed tubular body was formed, and the tubular body was sequentially passed through a die having a hole diameter of 10 mm through a small-diameter die to reduce the diameter. Finally, a deformed tube having a diameter of 8.5 mm was obtained.

Example 2 After the strip of Example 1 was plated with copper having a thickness of 5 μm, a deformed tube was formed under the same conditions as in Example 1. The porous tube was subjected to a heat treatment at 1130 ° C. for 15 minutes in an inert atmosphere to reflow the copper plating layer.

Example 3 An outer pipe of the same material having an inner diameter larger than the outer diameter of the tubular body of 9.5 mm and a thickness of 0.8 mm was used as an inner pipe. This was passed through a die hole of a die having a hole diameter of 9.5 mm to reduce the diameter, and finally a modified tube with an outer tube having a diameter of 9.5 mm was obtained.

Example 4 A deformed pipe formed by applying the same copper plating as in Example 2 was inserted into an outer pipe in the same manner as in Example 3 as an inner pipe, and the diameter was sequentially reduced with a die to form a double deformed pipe. Was manufactured. When the same heat treatment as in Example 2 was performed on the deformed pipe with the outer pipe, the inner and outer pipes were completely airtight.

Example 5 A floating plug having a groove height of 4 mm and a groove number of 6 was inserted into a round pipe having an outer diameter of 21.7 mm and a wall thickness of 0.8 mm, and the tip was squeezed to a small diameter, and the groove depth was 4 mm. The sheet was passed through a die having a hole diameter of 14 mm, and was drawn at a drawing rate of 15 mm / min. The obtained modified tube had a thickness of 0.6 mm and a width of unevenness of 3 mm.

Example 6 The surface of the deformed pipe formed in Example 5 was plated with copper,
It was inserted into the outer pipe in the same manner as in Example 4, and the diameter was sequentially reduced with a die to produce a double deformed pipe. When the same heat treatment as in Example 2 was performed on this double deformed pipe, the inner and outer pipes were completely airtight.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a material formed according to the present invention.

FIG. 2 is a side view of a forming roll for forming a tube material.

FIG. 3 is a cross-sectional view showing a state of transition from a material tube to a deformed tube by drawing a forming roll.

FIG. 4 is a process chart for manufacturing a long composite deformed tube.

FIG. 5 is a sectional view showing a composite deformed tube.

FIG. 6 is a diagram showing a hole surface and a sectional shape in an axial direction of a grooved die.

FIG. 7 is an axial surface of a grooved plug and an axial cross-sectional shape diagram.

FIG. 8 is an explanatory diagram of tube drawing using a floating plug.

FIG. 9 is an explanatory diagram of drawing a deformed pipe using a floating plug with a groove.

FIG. 10 is a sectional view of a four-groove deformed pipe.

FIG. 11 is a sectional view of a five-groove shaped pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate material 2 Corrugated 3 Convex roll element 4,5 Joining end face 6 Deformed pipe 7 Inner convex part 8 Groove part 11 Inner pipe 12a Strip plate 12 Outer pipe 13 Welding torch 14,19 Dice 15 Inner pipe top 16 Die with groove 16a With groove Die groove 17 Floating plug with groove 17a Protrusion of floating plug with groove 18 Floating plug 20 Material pipe 21 Pull-out pipe

 ────────────────────────────────────────────────── ─── Continued on front page (72) Inventor Tatsuya Komai 1028 Narita, Odawara-shi, Kanagawa F-term in Nishiyama Seisakusho Co., Ltd. (reference) 4E063 AA01 BB08 DA20 MA30 4E096 EA02 EA18 FA06 HA02

Claims (16)

[Claims] 1. A pipe member having a plurality of cross-sectional squares or corrugations of the same shape formed in a longitudinal direction is joined to each other in a longitudinal direction to form a tubular body whose cross section perpendicular to a tubular axis is uneven, and the tubular body is a die and / or a die. A method of manufacturing a deformed pipe, wherein a cross section perpendicular to the pipe axis direction is formed into a fold-like curved pipe wall by reducing the distance between the tips of the respective convex portions to the inside of the pipe by a forming roll. 2. The method for producing a deformed tube according to claim 1, wherein the cross section has a star-shaped or corrugated cross section of a different shape. 3. An a.S <S ₀ , a> between the inner cross-sectional area S perpendicular to the central axis of the pipe and the inner cross-sectional area S ₀ of the pipe before folding.
The method according to claim 1 or 2, wherein the method satisfies condition 10. 4. A fold that is parallel from a convex end to a concave end,
The method according to claim 1, 2 or 3, wherein the length is 2 to 10 times the width of the fold. 5. The method according to claim 1, wherein the material is a continuous long strip. 6. The method for producing a deformed pipe according to claim 1, wherein the end faces in the longitudinal direction of the plate are joined by any one of electric resistance welding, arc welding, gas welding, and hot forging. 7. The method according to claim 1, wherein a twisting process is performed at the same time to reduce the distance between the tips of the convex portions toward the inside of the deformed tube.
7. The method for producing a deformed pipe according to any one of claims 6 to 6. 8. A deformed pipe having a linear or helical irregularity formed on a longitudinal surface of a metal pipe is inserted into a pipe having an inner diameter larger than an outer diameter of the deformed pipe, and both of them are simultaneously dies and / or dies. The method for producing a deformed pipe according to any one of claims 1 to 7, wherein the diameter is reduced by a forming roll. 9. The method for producing a deformed pipe according to claim 1, wherein a pipe or plate having a plating layer formed on the surface is used, and after the pipe is formed, heat treatment is performed to reflow the plating layer. 10. A metal pipe is drawn by using a grooved die and a grooved floating plug to form a plurality of irregularities having the same shape in a direction perpendicular to the axial direction of the pipe, and then the deformed pipe is drawn out. A method for producing a deformed pipe, characterized in that a cross section perpendicular to the pipe axis direction is formed into a fold-like curved pipe wall by processing to reduce the distance between the tips of the convex portions toward the inside of the pipe. 11. The method for producing a deformed pipe according to claim 10, wherein the cross-sections are square or corrugated in different shapes. 12. An inner surface cross-sectional area S perpendicular to a central axis of the pipe,
A · S <S ₀ , a between the inner surface cross-sectional area S ₀ of the pipe before folding
The method for producing a deformed pipe according to claim 10 or 11, wherein the condition of> 10 is satisfied. 13. A fold that is parallel from the end of the projection to the end of the recess, the length of which is 2 to 10 times the width of the fold.
13. The method for producing a deformed tube according to 1 or 12. 14. The method for producing a deformed pipe according to claim 10, wherein the drawing of the deformed pipe is performed while twisting the pipe. 15. After forming irregularities linearly or spirally on a longitudinal surface of a metal tube with a die and a floating plug, the tube is inserted into a tube having an inner diameter larger than the outer diameter thereof. The diameter of both of them is reduced simultaneously by a die and / or a forming roll.
5. The method for producing a deformed pipe according to any one of the above items 4. 16. The method according to claim 10, wherein the raw tube is a long metal tube wound in a coil shape.