JPH09295035A - Manufacture of tube having grooved inside surface and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a tube having grooved inside surface by which tensile force to a metallic tube is decreased and the break of the metallic tube is prevented and a device therefor. SOLUTION: In the state of inserting a plug unit 26 into the metalic tube 1, by moving the metalic tube 1 from the left to the right (the direction of the arrow C) of the figure, the metallic tube 1 is impressed by rolling pressure in the position of a grooved plug 4 with roller dies 7 which is driven in the direction of the arrow B and with which the metallic tube 1 is extruded on the downstream side (the direction of the arrow C), pressed against the grooved plug 4, primary grooves 11 and fins 18 are continuously formed on the inside surface of the metallic tube 1 and the primary grooved tube 12 is formed. Furthermore, by moving the primary grooved tube 12 in the downstream direction, the primary grooved tube 12 is impressed by the rolling pressure in the position of the grooved plug 19 with plural balls 15 which are revolved like planetaries, pressed against the grooved plug 19, the secondary grooves 13 are continuously formed on the primary grooved tube 12 and the tube 14 having the grooved inside surface having the grooves 11 and the grooves 13 on the inside surface is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an inner grooved tube, and more particularly to a method for manufacturing an inner grooved tube in which a groove is formed on an inner surface of a metal tube by means of groove processing means and rolling pressure applying means. And its device.

[0002]

2. Description of the Related Art Conventionally, copper or copper alloy bare tubes have been used as heat transfer tubes for heat exchangers. Recently, as the heat transfer tube for such a heat exchanger, an inner grooved tube having high heat transfer performance to a fluid such as CFCs which changes in phase has been widely used.

Such a heat transfer tube for a heat exchanger is an inner grooved tube having fine spiral grooves on the inner surface for improving heat transfer performance, and recently, for improving heat transfer performance, two inner surface grooves are provided. It has a heavy inner grooved tube.

FIG. 4 shows an inner surface double grooved tube manufacturing apparatus which is one form of a conventional inner surface grooved tube manufacturing apparatus. The manufacturing apparatus rotates the outer peripheral surface of the metal tube 1 in a planetary manner in a direction orthogonal to the tube axis by applying a rolling pressure to the metal tube 1 in a radial direction on the outer peripheral surface of the metal tube. Two rolling pressure applying means 16 and 17 on the same axis for contracting 1 and a locking means 10 for locking the floating plug 2 inside the metal tube 1.
And the primary grooved plug 4 connected to the floating plug 2 by a connecting rod 3 is rotatably inserted into the metal tube 1 and is contracted by the rolling pressure applying means 16 to thereby form the metal tube. The first to process the primary groove 11 inside the first
The groove forming means and the secondary grooved plug 19 connected to the rear side of the primary grooved plug 4 by the connecting rod 3 are inserted into the primary grooved metal pipe 12 in a rotatable state, and the rolling is performed. The metal tube 12 with the primary groove is contracted by the pressure applying means 17
Is an apparatus for manufacturing an inner double-grooved pipe by a second groove processing means for processing the secondary groove 13 inside the.

That is, the rolling tools 16 and 17 which are the rolling pressure applying means of the manufacturing apparatus are arranged in two stages, and the grooves formed at the corresponding positions of the rolling tools 16 and 17 are connected to the floating plug 2. The grooved plugs 4 and 19 which are the means are arranged, and the double grooved processing is continuously performed on the inner surface of the metal tube 1. Therefore, by moving the metal tube 1 from the left to the right (direction of arrow C), the metal tube 1 is moved by the primary rolling tool 16 (sphere 15) that rotates like a planet at the position of the primary grooved plug 4. The tube is contracted and pressed against the primary grooved plug 4, and the primary groove 11 is continuously formed on the inner surface.
Secondary groove 1 by secondary rolling tool 17 and secondary grooved plug 19
3 is formed, and thus the double grooves 11 and 13 are continuously formed on the inner surface of the metal tube 1.

In this way, the inner surface double grooved tube having high heat transfer performance is manufactured by the manufacturing apparatus.

[0007]

However, according to the conventional apparatus for manufacturing the inner grooved tube, the rolling tool for rotating the outer peripheral surface of the metal tube 1 and the floating plug 2 in the metal tube 1 are used.
A rolling tool set (for example, a pair of the rolling tool 16 and the grooved plug 4) composed of grooved plugs connected to each other by a connecting rod 3 causes a large resistance to the metal pipe, and thus a large drawing force. It becomes necessary to easily break the metal tube. Further, in order to manufacture an inner grooved tube having a higher heat transfer performance, in the case where the groove on the inner surface of the metal tube is doubled or more, two or more rolling tool sets are required, and further resistance to the metal tube is increased. As a result, the pulling force increases and the risk of breaking the metal pipe increases.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method and apparatus for manufacturing an inner grooved pipe which reduces the resistance to the metal pipe, reduces the drawing force, and prevents the metal pipe from breaking.

[0009]

In order to achieve the above-mentioned object, the present invention applies a rolling pressure to the outer periphery of the metal pipe while extruding the moving metal pipe in the moving direction thereof, There is provided a method for manufacturing an inner grooved pipe, characterized in that a groove is formed on the inner peripheral surface of the metal pipe at a position where a pressure is applied.

In order to achieve the above-mentioned object, the metal is formed by driving the groove processing means at a predetermined position on the inner surface of the moving metal tube and the outer peripheral surface of the metal tube at the position of the groove processing means. An apparatus for manufacturing an inner grooved pipe for forming a groove on the inner peripheral surface of the metal pipe by a rolling pressure applying means for applying a rolling pressure to the outer circumference of the metal pipe while pushing the pipe in the moving direction.

That is, the inner grooved pipe manufacturing apparatus of the present invention is
By pushing the metal pipe to the downstream by driving the rolling pressure applying means and applying the rolling pressure to the outer periphery of the metal pipe, the tensile force to the metal pipe is reduced, the pulling force is reduced, and the metal pipe is broken. This is to prevent it.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The method and apparatus for manufacturing an inner grooved tube of the present invention will be described in detail below.

FIG. 1 shows an apparatus for manufacturing an inner double grooved tube which is an embodiment of the present invention. This apparatus is a groove processing apparatus provided with a driving rolling pressure applying means, a rolling pressure applying means, a first groove processing means, and a second groove processing means, and a floating plug 2.
, A connecting rod 3 and a drawing die 10.

The floating plug 2 is locked inside the metal tube 1 at the position of the drawing die 10 by passing the metal tube 1 through the drawing die 10.

Further, the driving rolling pressure applying means of the groove machining device is a roller die 7 composed of two rollers 8 and 9,
The roller die 7 drives the outer peripheral surface of the metal pipe 1 in the direction of arrow B to push the metal pipe downstream (direction of arrow C) and apply a rolling pressure in the radial direction of the metal pipe 1 to reduce the pressure. It is supposed to do.

Further, a plurality of spheres 15 rotating in a planetary shape, which are rolling pressure applying means of the groove processing apparatus, are pressed to press the metal tube 12.
Is in contact with the outer peripheral surface of the, and the inscribed circle diameter thereof has a predetermined dimension.

The grooved plug 4, which is the first groove processing means and in which a plurality of fine grooves 5 are formed on the outer periphery, is rotatably attached to the floating plug 2 via a connecting rod 3.

Further, the grooved plug 19 which is the second groove processing means and in which a plurality of fine grooves 20 are formed on the outer periphery is attached to the rear side (downstream direction) of the grooved plug 4 via the connecting rod 3. Has been.

The floating plug 2, the connecting rod 3, the grooved plug 4, and the grooved plug 19 constitute a plug unit 26. In the plug unit 26, the grooved plug 4 can be held at a predetermined position (the inside of the metal tube 1 at the position where the roller die 7 is installed) by the floating plug 2 engaging with the drawing die 10. Similarly, the grooved plug 19 can be held at a predetermined position behind the grooved plug 4 (inside the metal tube 12 where the plurality of balls 15 are installed). It has become.

Therefore, the plug unit 26 is provided in the metal tube 1.
By moving the metal pipe 1 from the left to the right in FIG. 1 (in the direction of arrow C) with the plug inserted, the metal pipe 1 is driven in the direction of arrow B at the position of the grooved plug 4 to move the metal pipe. Rolling pressure is applied by a roller die 7 that is pushed downstream (in the direction of arrow C), and is pressed against the grooved plug 4 so that the metal pipe 1
The primary groove 11 and the fin 18 are continuously formed on the inner surface of the
The next grooved tube 12 is formed.

Next, the primary grooved tube 12 is moved further downstream, so that the primary grooved tube 12 is rolled by a plurality of spheres 15 that rotate in a planetary manner at the position of the grooved plug 19. A pressure is applied to the grooved plug 19 by applying pressure to form a secondary groove 13 continuously on the inner surface of the primary grooved tube 12, and an inner surface grooved tube 14 having the groove 11 and the groove 13 on the inner surface is formed. It is formed.

With the structure of the manufacturing apparatus for the inner grooved tube as described above, in particular, by driving the rolling pressure applying means on the outer peripheral surface of the metal tube 1 in the direction of arrow B, the metal tube 1 is moved downstream (arrow C). Direction) and a roller die 7 composed of two rollers 8 and 9 for pushing in the radial direction of the metal tube 1 and applying a rolling pressure, the resistance to the metal tube is reduced and the pull-out force is reduced. It became possible to prevent the metal tube from breaking.

Here, FIG. 2 shows a sectional view AA 'of FIG. The roller die 7 is composed of two rollers 8 and 9, and the two rollers 8 and 9 are pressed to contact the outer peripheral surface of the metal tube 1, and the grooved plug 4 contacts the inner peripheral surface of the metal tube 1. . Further, the outer diameter of the metal tube 1 becomes a predetermined size by the inscribed circle (which contacts the outer circumference 360 degrees of the metal tube 1) formed by the arcuate grooves 6 of the two rollers 8 and 9. There is.

The embodiment of the present invention has been described above.
When there are multiple rolling pressure applying means in the manufacturing apparatus,
Any of the rolling pressure application means can be roller dies, and all the rolling pressure application means can be roller dies. For example, both of the two rolling pressure applying means 16 and 17 shown in FIG. 4 may be used as two driving rolling pressure applying means using roller dies. Here, when there are a plurality of means for applying the driving rolling pressure by the roller dies, it is necessary to synchronize the rotation speeds of the respective roller dies.

Further, as shown in FIG. 3, the roller die 2
1 may consist of three rollers 22, 23, 24. In such a case, the three rollers 22, 2
The inscribed circle formed by the circular grooves 3 and 24 is the metal pipe 1
It is necessary to make contact with the outer circumference of 360 degrees. That is, when the arcuate grooves of the plurality of rollers form an inscribed circle that contacts the outer circumference 360 degrees of the metal tube 1, the number of the rollers may be any number as long as it is two or more.

[0026]

As described above, according to the method and apparatus for manufacturing an inner grooved tube of the present invention, by driving the rolling pressure applying means, the metal tube is pushed downstream and contracted. Therefore, the resistance to the metal pipe is reduced, the pulling force is reduced, and the metal pipe can be prevented from breaking.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of an apparatus for manufacturing an inner grooved tube according to the present invention.

FIG. 2 is a schematic view showing one form of a cross section of a roller die according to the present invention.

FIG. 3 is a schematic view showing one form of a cross section of a roller die according to the present invention.

FIG. 4 is a schematic view showing an embodiment of a conventional apparatus for manufacturing an inner grooved tube.

[Explanation of symbols]

 1 Metal Pipe 2 Floating Plug 3 Connecting Rod 4 Groove Plug 5 Groove 6 Circular Groove 7 Roller Die 8 Roller 9 Roller 10 Drawing Die 11 Primary Groove 12 Primary Groove Pipe 13 Secondary Groove 14 Inner Groove Pipe 15 Ball 16 Rolling Tool 17 Rolling Tool 18 Fin 19 Groove Plug 20 Groove 21 Roller Die 22 Roller 23 Roller 24 Roller 25 Arc-Shaped Groove 26 Plug Unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B21H 3/00 B21H 3/00 B F28F 1/40 F28F 1/40 D

Claims (4)

[Claims] 1. A method for manufacturing an inner grooved pipe having a groove on an inner wall surface, wherein a metal pipe is moved in a pipe axis direction, and the metal pipe is pushed out in the moving direction by an outer periphery of the metal pipe, and a rolling pressure is applied. Is applied to the inside of the metal pipe at the position where the rolling pressure is applied, and a grooved plug that comes into contact with the inner wall surface is inserted to form a groove on the inner wall surface. Manufacturing method of attached tube. 2. A method for manufacturing an inner grooved pipe having a groove on an inner wall surface thereof, wherein a metal pipe is moved in a pipe axis direction, and the metal pipe is pushed in the outer peripheral direction of the metal pipe in the moving direction while being rolled. A grooved plug that contacts the inner wall surface is formed inside the metal pipe at a position where the rolling pressure is applied to form a groove on the inner wall surface, and the groove is formed on the inner wall surface. Inside the metal tube where is formed,
A method for producing an inner grooved pipe, wherein one or more grooved plugs that come into contact with the grooved inner wall surface are inserted to form multiple grooves on the grooved inner wall surface. 3. A manufacturing apparatus for an inner grooved pipe having a groove on an inner wall surface thereof, wherein a moving means for moving the metal pipe in a pipe axis direction and the metal by driving the outer periphery of the metal pipe in the moving direction. A drive rolling pressure applying means for applying a rolling pressure while pushing out the pipe, and a portion provided inside the position of the metal pipe to which the rolling pressure is applied, in contact with the inner wall surface to form a groove in the inner wall surface. An inner surface grooved pipe manufacturing apparatus, characterized by having groove processing means for forming a groove. 4. An apparatus for manufacturing an inner grooved tube having a groove on an inner wall surface thereof, wherein a moving means for moving the metal tube in a tube axis direction and the metal by driving the outer circumference of the metal tube in the moving direction. A drive rolling pressure applying means for applying a rolling pressure while pushing out the pipe, and a portion provided inside the position of the metal pipe to which the rolling pressure is applied, in contact with the inner wall surface to form a groove in the inner wall surface. Groove forming means for forming a groove, a rolling pressure applying means for applying a rolling pressure to the outer circumference of the metal tube having the groove formed on the inner wall surface, and the rolling pressure for the grooved metal tube is applied. An inner surface grooved pipe manufacturing apparatus, comprising groove processing means provided inside the position where the grooved inner wall surface is contacted to form multiple grooves on the grooved inner wall surface.