JP3642368B2 - Fin tube and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
INDUSTRIAL APPLICABILITY The present invention is widely used in oil cooling pipes for automobiles and construction machinery, air conditioners that adjust the temperature and humidity of residential spaces, refrigerators and refrigerators that keep food fresh and preserved, reaction tubes for chemical equipment, and the like. And its manufacturing method.
[0002]
[Prior art]
Conventionally, oil cooling pipes for automobiles and construction machinery, air conditioners that adjust the temperature and humidity of living spaces, refrigerators that preserve food freshness, and reaction towers for chemical facilities are rolled around metal pipes. A fin tube formed by integrally forming spiral fins by processing, or a metal tube wound with fins using a fin winding machine that winds the fins directly around the metal tube is immersed in a brazing material bath and brazed. In addition, many fin tubes obtained by continuously brazing or welding the inner peripheral end of the helical fin to the outer peripheral surface of the metal tube have been used.
[0003]
[Problems to be solved by the invention]
The conventional fin tube is formed as described above, and quickly dissipates the heat transferred from the heated fluid flowing inside the metal tube to the outside without accumulating in the metal tube. It is something that has.
However, in the production thereof, it takes a long time to complete the product, and the heat conduction rate transmitted from the heated fluid to the metal tube is not sufficient, so improvements regarding these points have been desired.
[0004]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a fin tube having a high heat dissipation effect and a reduced manufacturing time and a high strength fin tube and a method for manufacturing the same.
[0005]
[Means for Solving the Problems]
As a result of repeated research and development, the present inventors have achieved the object by adopting a simple processing method in order to solve the above problems.
The details are shown below.
[0006]
The fin tube which concerns on this invention is a fin tube comprised by the metal strip and the metal strip wound around this metal tube, Comprising: The inner peripheral edge part of a metal strip is the helical form formed in the outer surface of a metal tube In the fin tube in which a spiral protrusion is formed on the inner surface corresponding to the outer surface of the fin tube formed by fitting and winding in the groove or the spiral groove of the metal tube, the spiral The metal strip wound around the inner circumferential end portion is formed into a corrugated shape, and the corrugated width formed at the inner peripheral end portion is the groove width of the spiral groove formed on the outer surface of the metal tube. It is characterized by being formed substantially equally .
[0007]
In the fin tube according to the present invention, at least both ends in the longitudinal direction are fixed to the metal tube, and the spiral groove is formed by plastic working, and the bottom surface of the spiral groove can be formed with irregularities. .
[0008]
The fin tube manufacturing method according to the present invention is a fin tube manufacturing method including a metal tube and a metal strip wound around the metal tube, and a spiral groove and / or an outer surface of the metal tube. Or the manufacturing method of the fin tube which forms the helical protrusion part corresponding to the said spiral groove on the inner surface of a metal tube, fits and winds the inner peripheral edge part of a metal strip to the said spiral groove And forming at least the inner peripheral end of the metal strip in a corrugated shape, forming a spiral groove having a groove width substantially equal to the width of the corrugation on the outer surface of the metal tube, and forming the corrugation in the spiral groove. Including a step of fitting and winding .
In this case, it is not preferable to form a helical protrusion of the spiral grooves and the inner surface of the outer surface of the metal pipe at the same time.
[0009]
Further, in the present invention, at least both ends in the longitudinal direction of the metal strip fitted and wound around the metal tube and the spiral groove are fixed to the metal tube or formed on the outer surface of the metal tube. Corresponding to the spiral groove, a fin tube is manufactured by forming a spiral protrusion on the inner surface of the metal tube, or a metal strip is fitted into the spiral groove while rotating the metal tube. When the spiral groove is formed on the outer surface of the metal tube or the spiral groove is formed on the outer surface of the metal tube, irregularities can be formed on the bottom surface of the spiral groove formed on the outer surface of the metal tube.
[0010]
Furthermore, when the fin tube is formed, the metal strip is spirally wound around the outer surface of the metal tube so that the plate surface of the metal strip is positioned in a direction perpendicular to the outer surface of the metal tube. The inner peripheral end of the strip is brought into close contact with the outer surface of the metal tube, and is then pressed radially from the outer peripheral end of the metal strip in the direction of the central axis of the metal tube. A spiral groove is formed on the outer surface by a metal band wound spirally, and a spiral protrusion corresponding to the spiral groove is formed on the inner surface of the metal tube. More preferably, the inner peripheral end of the metal strip is fitted into the groove.
In this case, when the metal strip is spirally wound around the outer surface of the metal tube, the metal tube is rotated to press the metal strip against the outer surface of the metal tube, thereby plastic working the tube wall of the metal tube. It is more preferable to form a spiral groove accompanying the above and simultaneously wrap a metal strip in the spiral groove.
In addition, the metal tube can be fixed to at least both ends in the longitudinal direction of the spiral metal strip that is fitted and wound around the metal tube.
[0011]
In the present invention, a spiral groove is formed on the outer surface of a metal tube, the inner peripheral end of a metal strip is fitted and wound around the spiral groove, and the metal tube is fitted and wound. The spiral metal strip and the metal pipe are integrally brazed at both ends in the longitudinal direction of the strip, and are fixed by appropriate means such as welding and caulking, or the spiral groove and the inner circumference of the metal strip Since the fin tube is formed by brazing or welding the end portion together over the entire surface, and the spiral protrusion is formed on the inner surface of the metal tube, turbulent flow is caused to the fluid flowing on the inner surface of the metal tube. This increases the heat transfer rate from the fluid to the metal tube, resulting in a higher heat dissipation effect of the fin tube.
When the metal strip is spirally wound around the outer surface of the metal tube, the metal tube is rotated so that the metal strip extends radially from the outer peripheral end of the metal strip to the central axis direction of the metal tube. The metal strip is pressed against the outer surface of the metal tube, and if necessary, the metal strip is strongly pulled in a direction opposite to the winding direction of the metal strip by the rotation of the metal tube. It is efficient to form a spiral groove accompanying the processing and simultaneously fit and wrap a metal strip around the spiral groove.
Thus, in the present invention, the time required for manufacturing the fin tube can be remarkably shortened as compared with the conventional case.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will now be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing an embodiment of the present invention, where (a) is a side view, (b) is a front view, FIG. 2 is a side sectional view of the embodiment of FIG. 1, and FIG. 4A is a side view, FIG. 4 is a partial sectional view along a spiral groove of another embodiment of the present invention, and FIG. 5 is still another embodiment of the present invention. It is explanatory drawing which shows the method of an Example, (a) is a side view, (b) is the fragmentary sectional view on the VV line of (a), FIG. 6 is an expanded sectional view which shows the process of the method of FIG. 5A is a partial cross-sectional view along the line AA in FIG. 5B, FIG. 5B is a partial cross-sectional view along the line BB in FIG. 5B, and FIG. 5C is a cross-sectional view along the line C- in FIG. FIG. 7 is a partial sectional view on line C, FIG. 7 is a view showing still another embodiment of the present invention, (a) is a partial sectional perspective view of the embodiment of the partial waveform, and (b) is one embodiment of the entire waveform. FIG. 8 is a cross-sectional perspective view of a part, and FIG. FIG. 9 is a perspective view showing a method of making a cut in and bending the portion outward and stopping, FIG. 9 is a diagram showing a metal band fitted on a metal tube by bending the end portion of the metal band material parallel to the tube axis on the metal tube. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a method of spot welding by pinching bent bent portions and then crimping them, wherein 1 is a metal tube made of iron, stainless steel, copper, brass, aluminum, etc., 2 is a spiral on the outer surface of the metal tube 1 A groove 3 formed into a shape, 3 is a metal band made of the same material as the metal tube 1 and is wound around the spiral groove 2, and 4 is an inner peripheral end of the metal band 3. Reference numerals 5a and 5b denote both end portions thereof, and 6 denotes a spiral protrusion formed on the inner surface of the metal tube 1.
[0013]
In order to manufacture such a fin tube, as shown in FIG. 3, a metal tube in which a spiral groove 2 is formed in advance on its outer surface, and preferably a spiral protrusion 6 is also formed on its inner surface. The inner peripheral end 4 of the metal strip 3 is wound so as to be fitted into the spiral groove 2 while rotating 1, or while rotating the metal tube 1 as shown in FIGS. 5 and 6 When the metal strip 3 is spirally wound around the outer surface of the metal tube, at least two pressing rollers 7 (two pressing rollers 7 and one guide roller 7 in FIG. ′ Is shown, but these rollers are omitted in FIG. 6) and pressed against the central axis direction of the metal tube 1 in the radial direction (arrow (A) direction). Further, the winding direction of the metal strip 3 by the rotation of the metal tube 1 Is the opposite direction, the metal strip 3 is strongly pulled in the tangential direction (arrow (b) direction) of the outer peripheral surface of the metal tube 1, and the tube wall of the metal tube 1 is plastically processed, and the outer surface thereof is spiral. The concave groove 2 is formed on the inner surface of the metal tube corresponding to the helical concave groove, and at the same time, the metal strip 3 is fitted into the helical concave groove 2. Form.
[0014]
The metal strip 3 wound so as to fit in the spiral groove 2 in this way is fitted with the inner peripheral end 4 of the spiral groove 2, so that the metal strip 3 is the metal tube 1. However, in order to prevent the positional deviation and to firmly fix it, both ends 5a and 5b of the metal strip 3 are then brazed or welded to the metal tube 1. Or, for example, as shown in FIG. 8, the end portions 5a and 5b of the metal strip 3 are overlapped with the spiral winding portion in front thereof, and a cut 8a is made in the overlapping portion 8, and the cut 8a is formed. The plurality of sliced pieces 8b are alternately bent outward from the root portion, or the overlapped portion 8 is simply spot-welded (not shown), or as shown in FIG. 9, the end portions 5a and 5b of the metal strip 3 are Bend part 5c on metal tube 1 by bending it parallel to the tube axis The bent portion 5c is sandwiched between the metal band 9 that is externally fitted to the metal tube 1 and the bent portion 5c is integrated with the bent portion 5c by spot welding 9b. A method of fixing the band to the metal tube 1 by caulking the outer fitting portion of the tube 1 can be used. If necessary, the entire inner peripheral end 4 of the metal strip 3 can be brazed or welded into the spiral groove 2 of the metal tube 1.
[0015]
In addition, it is preferable that the bottom surface of the spiral groove 2 is provided with irregularities made of axial streaks, satin or the like, as shown in FIG. Furthermore, the metal strip 3 wound spirally as shown in FIG. 6 is formed such that its outer peripheral end is linear and its inner peripheral end 4 is corrugated as shown in FIG. As shown in b), the width of the corrugation formed in the inner peripheral end 4 is formed on the outer surface of the metal tube 1 along the width direction (the height direction when the metal strip is wound). When formed substantially equal to the groove width of the formed spiral groove 2, the metal strip 3 is stabilized in the groove 2, the heat transfer area is increased, and heat transfer is ensured, so that the heat radiation effect is further increased. Since it improves, it is preferable.
[0016]
The corrugation is preliminarily gear-processed on a part or all of the width direction of the metal strip 3, and the spiral groove 2 is formed in the metal tube 1 by pressing as described above and pulling as required. At the same time, when the metal strip 3 is fitted and wound around the concave groove, it can be formed together with this fitting and winding. That is, when the metal strip 3 is wound, the gear-processed portion is plastically deformed in a bowl shape due to a difference in elongation rate and becomes a waveform.
[0017]
【Example】
Examples of the present invention will be described below.
[Example 1]
On the outer surface of the metal pipe 1 made of a steel pipe having an outer diameter of 12.7 mm, a wall thickness of 1.0 mm, and a length of 4 m, a helical pitch is 4 mm, a depth is 0.3 mm, and a width is 0.55 mm. The spiral groove 2 is formed. On the other hand, a metal strip 1 made of steel having a thickness of 0.5 mm and a plate width of 6 mm is attached to the metal tube 1 so that the inner peripheral end 4 of the metal strip 3 is fitted into the spiral groove 2. Winding while rotating and fitting the spiral metal strip 3 and the metal tube 1 together at both ends 5a, 5b in the longitudinal direction of the metal strip 3 wound around the concave groove 2 of the metal tube 1 The fin tube was formed by fixing. The obtained fin tube had high fin strength and satisfactory heat dissipation effect.
[0018]
[Example 2]
On the outer surface of the metal tube 1 made of a copper tube having an outer diameter of 6.4 mm, a thickness of 0.5 mm, and a length of 6 m, the pitch is 3 mm using a roll or the like, the depth is 0.5 mm, and the width is At the same time as forming the spiral groove 2 of 0.55 mm, the spiral protrusion 6 having a protrusion height of 0.5 mm is formed on the inner surface of the metal tube 1 by plastic working corresponding to the spiral groove 2. . On the other hand, a metal strip 3 made of steel having a thickness of 0.5 mm and a plate width of 7 mm is wound and wound so that the inner peripheral end 4 of the metal strip 3 fits into the spiral groove 2. A fin tube was manufactured in the same manner as in Example 1 except that both ends 5a and 5b in the longitudinal direction of the metal strip 3 were fixed to the metal tube 1 as shown in FIG. As a result, the production time was short and the heat dissipation effect was satisfactory.
[0019]
[Example 3]
As shown in FIG. 4, when forming the spiral groove 2 on the outer surface of the metal tube 1, stripes with a height difference of 0.1 mm are formed on the bottom surface of the spiral groove 2, and then in the axial direction. The inner peripheral end 4 of the metal strip 3 is fitted and wound around the spiral concave groove 2 having an uneven surface composed of streaks on the bottom, and both ends 5a and 5b in the longitudinal direction of the wound metal strip 3 are connected to the metal tube. A fin tube was manufactured in the same manner as in Example 1 except that it was fixed to No. 1 as shown in FIG. The obtained fin tube had high strength and satisfactory heat dissipation effect.
[0020]
[Example 4]
The metal tube 1 is rotated on the outer surface of the metal tube 1 made of STKM11A having an outer diameter of 15 mm and a wall thickness of 0.9 mm so that the plate surface of the metal strip 3 is positioned in a direction orthogonal to the outer surface of the metal tube 1. When the metal strip 3 made of SPHC having a plate width of 9 mm and a thickness of 0.9 mm is spirally wound at a pitch of 4.0 mm, the inner peripheral end 4 of the metal strip 3 is attached to the outer surface of the metal tube 1. As shown in FIG. 5, two rolls 7 are used strongly in the radial direction (arrow (A) direction) from the outer peripheral end 8 of the metal strip 3 to the central axis direction of the metal tube 1 as shown in FIG. Press contact. Due to the pressure contact of the metal strip 3, the tube wall of the metal tube 1 is plastically processed so that the spiral groove 2 is formed on the outer surface, and the spiral groove 2 is formed on the inner surface of the metal tube 1 corresponding to the spiral groove 2. At the same time as the protrusion 6 is formed, the inner peripheral end 4 of the metal strip 3 is fitted and wound around the spiral groove 2 formed on the outer surface of the metal tube 1. Thereafter, at least at both ends 5a and 5b in the longitudinal direction of the spiral metal strip 3 fitted to the metal tube 1, the spiral metal strip 3 and the metal tube 1 are integrally welded and fixed to each other, and the fin tube is fixed. Formed. In this case, the time required for production was extremely shortened and the heat dissipation effect was satisfactory.
[0021]
[Example 5]
On the outer surface of the metal tube 1 made of SUS 304L having an outer diameter of 27.0 mm, a wall thickness of 0.7 mm, and a length of 3 mm, a thickness of 1.0 mm and a plate width of 10 mm are preliminarily set to 8 mm in the width direction. When the metal strip 3 made of SUS 304 that is geared over is wound helically at a pitch of 6.0 mm, the radial direction (arrow (A) direction) with respect to the central axis direction of the metal tube 1 as in the fourth embodiment. ) In the direction opposite to the winding direction of the metal strip 3 by the rotation of the metal tube 1 and the tangential direction (arrow (b) direction) of the outer peripheral surface of the metal tube 1 ) The metal strip 3 is pulled strongly. By pressing and pulling the metal strip 3, the tube wall of the metal tube 1 is plastically processed so that the outer surface has a spiral groove 2 and the inner surface of the metal tube 1 corresponds to the spiral groove 2. At the same time as the spiral protrusion 6 is formed, the inner peripheral end 4 of the spiral metal strip 3 is fitted in the spiral groove 2 formed on the outer surface of the metal tube 1, and the metal strip 3 The geared inner peripheral end 4 side is deformed due to the difference in elongation rate of the metal strip 3 and has a waveform as shown in FIG. The width of the formed waveform is substantially equal to the groove width of the spiral groove 2 formed at the same time. Thereafter, at least both ends 5a and 5b in the longitudinal direction of the metal strip 3 were fixed by temporary welding, and the inner peripheral end 4 was Ni brazed over the entire length to produce a fin tube. As a result, the time required for production was short, there was no displacement of the metal strip relative to the metal tube, and the heat dissipation effect was satisfactory.
[0022]
【The invention's effect】
In the present invention, the spiral groove is formed on the outer surface of the metal tube, and the metal strip is fitted into the spiral recess to integrally form the wound metal tube and the metal strip. There is no variation in the pitch of the strip, and the boundary on the inner surface of the metal tube is created by the spiral protrusion provided inside the metal tube, which gives a swirling force to the fluid moving inside the metal tube and creates turbulent flow. By making the layer thinner, it became possible to produce fin tubes with more effective heat dissipation.
Further, when the spiral metal strip and the metal tube are integrated, it is preferable that the metal tube and the spiral metal strip are fixed to the metal tube at least at both ends in the longitudinal direction. Compared to the above, it is possible to finish the product with a significantly shorter production time, and to provide a fin tube with high strength and satisfactory heat dissipation.
[Brief description of the drawings]
1A and 1B are diagrams showing an embodiment of the present invention, in which FIG. 1A is a side view and FIG. 1B is a front view.
FIG. 2 is a side sectional view of the embodiment of FIG.
3A and 3B are diagrams for explaining a method according to the present invention, in which FIG. 3A is a side view, and FIG. 3B is a front view.
FIG. 4 is a partial cross-sectional view along a spiral groove according to another embodiment of the present invention.
5A and 5B are explanatory views showing a method according to still another embodiment of the present invention, in which FIG. 5A is a side view, and FIG. 5B is a partial cross-sectional view taken along the line VV in FIG.
6 is an enlarged cross-sectional view showing the steps of the method of FIG. 5, wherein (a) is a partial cross-sectional view along the line AA in FIG. 5 (b), and (b) is along the line BB in FIG. 5 (b). (C) is a fragmentary sectional view on the CC line of FIG.5 (b).
7A and 7B are views showing still another embodiment of the present invention, in which FIG. 7A is a partially sectional perspective view of an embodiment showing a partial waveform, and FIG. 7B is a partially sectional perspective view of an embodiment showing an entire waveform; It is.
FIG. 8 is a perspective view showing a method of polymerizing metal strips and making a cut in the part to bend and stop the part outward.
FIG. 9 is a perspective view showing a method of bending a metal band member end portion in parallel with a tube axis on a metal tube, sandwiching the bent portion with a metal band fitted on the metal tube, and spot welding to stop It is.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Metal pipe 2 Helical groove 3 Metal strip 4 Inner peripheral edge part 5a One end part 5b of a longitudinal direction The other end part 6 of a longitudinal direction 6 Spiral protrusion part 7 Roller

Claims (4)

A fin tube composed of a metal tube and a metal strip wound around the metal tube, and the inner peripheral end of the metal strip is fitted into a spiral groove formed on the outer surface of the metal tube. In the fin tube in which the spiral projection is formed on the inner surface corresponding to the outer surface in which the spiral concave groove of the fin tube or the metal tube is formed, the metal strip wound in the spiral is In addition, at least the inner peripheral end is formed in a corrugated shape, and the width of the corrugated formed in the inner peripheral end is formed substantially equal to the groove width of the spiral groove formed in the outer surface of the metal tube. Characteristic fin tube. A method for manufacturing a fin tube comprising a metal tube and a metal strip wound around the metal tube, wherein the outer surface of the metal tube corresponds to the spiral groove and / or the inner surface of the metal tube corresponds to the spiral groove. In the manufacturing method of a fin tube, the inner circumferential end of the metal strip is formed by fitting and winding the inner circumferential end of the metallic strip in the spiral groove, Forming a spiral groove having a groove width substantially equal to the width of the waveform on the outer surface of the metal tube, and fitting and winding the waveform on the spiral groove. The manufacturing method of the fin tube. The metal strip is spirally wound around the outer surface of the metal tube so that the plate surface of the metal strip is positioned in a direction orthogonal to the outer surface of the metal tube, and the inner peripheral end of the metal strip is connected to the metal tube A metal strip that is in close contact with the outer surface of the metal tube, and is then pressed in a radial direction from the outer peripheral end of the metal strip to the central axis direction of the metal tube. A spiral groove is formed by the material, and a spiral protrusion is formed on the inner surface of the metal tube corresponding to the spiral groove, and at the same time, an inner peripheral end of the metal strip is formed in the spiral groove. A fin tube manufacturing method, wherein the fin tube is fitted. When the metal strip is spirally wound around the outer surface of the metal tube, the metal tube is rotated so that the metal strip is pressed against the outer surface of the metal tube, thereby spiraling the tube wall of the metal tube due to plastic working. 4. The method of manufacturing a fin tube according to claim 3, wherein a metal strip is fitted and wound around the spiral groove at the same time as forming the groove.

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