JP2002263770A - Manufacturing device of grooved heat transfer pipe, and fin form rolling roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the service life of a fin form rolling roll by preventing the fin form rolling roll from being chipped in a step of form rolling a fin on a metal plate bar. SOLUTION: A manufacturing device of a grooved heat transfer pipe comprises the fin form rolling roll 24 and a receiving roll 26 for form rolling the W-shaped fin 2 by holding and rolling a metal plate bar T, a plurality of forming rolls 30 for forming the plate bar with the fin 2 formed thereon in a tubular shape so that the fin 2 is positioned on the inner or outer circumferential side, and welding mechanisms 32, 34 and 36 for heating, butting and welding both edges of the plate bar formed in a tubular shape. The fin form rolling roll 24 comprises a plurality of split rolls 24B-24E with fin form rolling grooves 25 formed on the outer circumferential surface thereof disposed coaxially with each other, and in these split rolls, end faces on the side in which the respective fins 2 are formed last on the plate bar T according as the fin form rolling roll 24 is rolled are diffusion-welded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grooved heat transfer tube manufacturing apparatus in which fins are formed on the inner surface or outer surface of a metal tube to enhance heat exchange efficiency, and a fin roll.

[0002]

2. Description of the Related Art A grooved heat transfer tube is mainly used as an evaporating tube or a condensing tube in a heat exchanger such as an air conditioner or a refrigerator. Recently, a zigzag fin has been formed over almost the entire inner surface. The heat transfer tube formed with is manufactured.

FIG. 10 is a partially developed plan view showing an example of a grooved heat transfer tube 1 in which zigzag fins 2 are formed. As shown in FIG. 11, the grooved heat transfer tube 1 uses a fin rolling roll 10 having a rolling groove 12 on an outer peripheral surface on a surface of a portion excluding both side edges 6 of a metal plate strip T. It is manufactured by forming zigzag (W-shaped) fins 2 and grooves 4, rolling the plate material T into a tubular shape with the fin forming surface inside, and welding the butted side edges 6. The fins 2 may be formed on the outer peripheral surface side of the grooved heat transfer tube 1. In that case, the fin 2 and the groove 4 are formed using the fin roll 10 similar to the above,
The plate member T may be rounded into a tubular shape with the fin forming surface on the outer peripheral surface side, and the butted side edges 6 may be welded.

Since it is generally difficult to form the zigzag rolling groove 12 on the outer peripheral surface of a single roll with high precision as described above, usually, the fin rolling of the fin rolling roll 10 is performed. A plurality of (in this case, four) regions are formed by dividing the groove forming region along the refraction point of the fin 2.
And a simple spiral groove is formed on the outer peripheral surface of each of the divided rolls 10B to 10E. The split rolls 10B to 10E are sandwiched between a pair of side rolls 10A, and the side rolls are pressed by a fastening mechanism, and all the rolls 10A to 10E are pressed.
10E was fixed to a rotating shaft.

[0005]

Recently, it has been required to increase the line speed in order to increase the production efficiency of grooved heat transfer tubes. Also, in order to increase the heat exchange efficiency of the grooved heat transfer tubes, it has been required to form fins that are taller than before. When the line speed is increased or a tall fin is rolled in this manner, the end of the fin rolling groove is easily damaged at the boundary between the split rolls 10B to 10E, and the life of the fin rolling roll 10 is short. There was a problem. Since the fin roll 10 is an expensive component, a short life thereof increases the production cost of the grooved heat transfer tube.

This problem is particularly caused by the rotation of the fin rolling roll 10 in the region A where the individual fins 2 are finally formed on the sheet material (that is, the fins 2 are sharpened toward the upstream in the traveling direction of the sheet material). This was remarkable in a region B facing the refraction portion of the fin 12). The reason can be explained as follows. That is, in the process of rolling the fins 2 on the sheet material T by the fin rolling roll 10 as described above, the individual rolling grooves 12 are formed.
Are formed obliquely with respect to the circumferential direction of the roll, so that the fins 2
The above is gradually formed from one part to another part.

At this time, from the rolling start point of each fin to the rolling end point, as shown by an arrow Y in FIG. In the rolling end region A, the filling pressure into the groove becomes the highest. As a result, in the region B, an excessive force is repeatedly applied to the end of each fin rolling groove 12, and the partition wall between the fin rolling grooves 12 is easily damaged. Further, since the metal material repeatedly intrudes into the small gaps between the boundaries between the divided rolls 10B and 10C and between the divided rolls 10D and 10E, the groove shape is deteriorated at these boundaries, and the roll life is shortened. .

Further, in the fin rolling end region A, the filling pressure of the metal material into the groove becomes the highest, so that the fins 2 become unnecessarily high as compared with the rolling start portion. When the fin 2 exits from the fin, the fin 2 easily interferes with the edge of the fin rolling groove 12. As a result, in the region B on the outer periphery of the roll corresponding to the region A, there is a problem that the edge of the fin rolling groove 12 is damaged early, and the life is further shortened.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is difficult for a fin rolling roll to be chipped in a process of rolling a fin on a metal plate strip, and a grooved transmission that can extend the life of the fin rolling roll. It is an object of the present invention to provide a heat tube manufacturing apparatus and a fin roll having a long life.

[0010]

In order to solve the above-mentioned problems, an apparatus for manufacturing a grooved heat transfer tube according to the present invention is characterized in that a fin is formed on one surface of a metal strip by rolling the metal strip. A fin rolling roll and a receiving roll to be rolled, and a plurality of forming rolls for forming the plate material on which the fins are formed into a tubular shape so that the fins are located on the inner peripheral side or the outer peripheral side, And a welding mechanism for heating and butt-welding both end edges of the formed strip material, wherein the fin rolls are formed coaxially with fin roll grooves formed on an outer peripheral surface. A plurality of split rolls are provided, and these split rolls are such that the end faces on the side where individual fins are finally formed on the plate material with the rotation of the fin rolls are diffusion bonded to each other. It is characterized by.

[0011] A thickness adjusting mechanism for rolling the plate material and partially adjusting the thickness thereof may be provided at a stage preceding the fin rolling roll. This thickness adjusting mechanism has a function of relatively reducing the thickness of the plate material in a region near the diffusion bonding surface where the fin rolling roll finally forms individual fins on the plate material. .

On the other hand, the fin roll of the present invention comprises a plurality of split rolls having fin roll grooves formed on the outer peripheral surface and arranged coaxially with each other, and each of these split rolls is only diffusion bonded to one side. It is characterized by having been done.

[0013] Adjacent split rolls may have different angles of the fin rolling grooves formed in them. Further, on both sides of the fin roll, side rolls having a smooth surface may be arranged coaxially, and these side rolls may be exchangeable with other side rolls having different outer diameters.

[0014] Further, the outer diameter of the fin roll and / or the receiving roll may be such that the fin roll has a diffusion surface facing a region where individual fins are finally formed on the strip with the rotation of the fin roll. The diameter may be relatively reduced in the region near the bonding surface.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 is a side view showing a first embodiment of an apparatus for manufacturing a grooved heat transfer tube according to the present invention. This embodiment is for forming a grooved heat transfer tube having a W-shaped fin as in FIG. 11, but the present invention is directed to a V-shaped fin or a “VVV” type that is bent five times. The present invention can be similarly applied to manufacture of a grooved heat transfer tube having fins.

In the figure, reference numeral 20 denotes an uncoiler for continuously feeding out a metal plate material T having a constant width and a constant thickness. The fed plate material T is arranged to face each other via a pair of pressing rolls 22. It is passed between the fin rolling rolls 24 and the receiving rolls 26 that have been formed. And the fin rolling roll 24
As a result, the W-shaped fins 2 and the grooves 4 and the flat side edges 6 (see FIG. 11) are formed on the surface of the plate material T, while the back surface of the plate material T is kept smooth. It is.

As shown in FIG. 2, the fin rolls 24 are divided into coaxially arranged annular divided rolls 24B to 24E having the same diameter and divided rolls 24B to 24E.
E and a pair of annular side rolls 24A coaxially fixed to both sides of the shaft E, as shown in FIG.
Are fixed coaxially to

An annular flange portion 29 is integrally formed on the outer peripheral surface on one end side of the roll shaft 27, and a male screw portion 33 is formed on the outer peripheral surface on the other end side. Flange part 29
Side roll 24A, divided rolls 24B to 24 integrally joined to outer peripheral surface 27A between
E, the side rolls 24A are passed in order, and the nuts 31 are screwed into the male screw portions 33, so that the rolls 24A to 24A
E is fixed to the roll shaft 27. Roll 24A-2
Even if the inner diameter of 4E at room temperature is made slightly smaller than the outer diameter of the outer peripheral surface 27A, the rolls 24A to 24E are heated to a high temperature and then baked on the outer peripheral surface 27A to further prevent rattling. Good.

On the outer peripheral surfaces of the split rolls 24B to 24E,
As shown in FIG. 2, a number of spiral fin rolling grooves 25 are formed in parallel at a constant pitch over the entire surface. The fin rolling grooves 25 between the adjacent split rolls are plane-symmetric with respect to the joining surface of the split rolls. Thus, when the plate material T is rolled, the W-shaped fins 2 and A large number of grooves 4 are formed at a constant pitch.

The feature of this embodiment is that the split roll 24B
To 24E, the end face on the side where the individual fins are finally formed on the plate material T with the rotation of the fin rolls 24,
That is, they are diffusion bonded to each other. That is, in the illustrated example, the split rolls 24B and 24C, 24D and 24E
Are bonded by diffusion bonding, and the split rolls 24C and 2C
The contact surface of 4D is not diffusion bonded. Therefore, the split rolls 24C and 24D are separable. In a conventional split-type roll, it is usually impossible to perform diffusion bonding between the split rolls. The reason is that if the divided rolls are mechanically pressed from both sides and fixed without diffusion bonding, there will be no trouble during rolling in normal use, and if the divided rolls are joined to each other, damage will not occur. This is because it becomes impossible to replace the resulting split rolls individually.

The inventors of the present invention have also attempted to strongly press and fix each of the divided rolls with a fastening mechanism. However, no matter how much the mechanical fastening force is increased, it is possible that the breakage of the boundary between the divided rolls may occur. They have found that they cannot be sufficiently prevented, and as a result of research, have reached the present invention. Split roll 24
If the contact surfaces of B and 24C and 24D and 24E are diffusion bonded to each other, the split rolls 24B and 24C and 24D and 24E cannot be separated, but the split rolls 24B and 24E cannot be separated.
C and the split rolls 24D and 24E can be replaced as an integral unit, and the life of the fin rolls 24 can be extended, so that the split rolls 24B and 24C and 24D and 24E cannot be separated. Does not matter.

In order to perform diffusion bonding, the fin rolling grooves 25 of the pair of divided rolls 24B and 24C, 24D and 24E are formed.
After aligning the positions, each pair is pressed against each other by using a jig and brought into close contact with each other, and the whole is put into a vacuum heating furnace and heated to around the recrystallization temperature of the roll material. As a result, atoms are diffused at the respective contact surfaces of the split rolls 24B and 24C and 24D and 24E, and are joined to each other. By employing the diffusion bonding, the bonding of the split rolls 24B to 24E formed of a high melting point material such as a cemented carbide can be easily performed. Further, according to the diffusion bonding, the deformation of the bonding surface is extremely small, and there is no inclusion such as a brazing material. Therefore, the shape accuracy does not decrease as compared with the case where the diffusion bonding is not performed.

Thus, the split rolls 24B and 24C, 2
By diffusion bonding of 4D and 24E, even the end faces of the groove partition walls (protrusions between the fin rolling grooves 25) butted at the bent portions of the fin rolling grooves 25 are integrally connected. You. Therefore, when the line speed of the rolling is increased and / or on the side where the individual fins are finally formed on the plate material with the rotation of the fin rolling rolls 24, the bent portions of the fin rolling grooves 25 are formed. Even when an excessive pressure is applied to the fin roll 24, the end of the groove partition wall butted at the bending portion is less likely to be lost, and the life of the fin roll 24 can be extended.

In this embodiment, since the side rolls 24A are not diffusion-bonded to the split rolls 24B to 24E, replacement of the side rolls 24A is easy. The side rolls 24A have a function of forming finless portions 6 having a fixed width on both side edges of the plate material T, respectively, and the width and thickness of these finless portions 6 greatly affect the electric resistance welding. Therefore, when the material and thickness of the plate material T are changed, it is necessary to change the size and shape of the side roll 24A in order to adjust the width and thickness of the finless portion 6. In the embodiment, the change can be easily performed. It is desirable that several types of side rolls 24A having different dimensions are prepared in advance. Side roll 2
The end of 4A may be chamfered or may be tapered.

Since the split rolls 24B and 24C and the split rolls 24D and 24E can be exchanged as an integral unit, only the unit on which the chip has occurred needs to be exchanged. The required cost can be reduced.

If the direction of the axis of the fin rolls 24 is reversed, the material flows toward both ends and the center of each W-shaped fin 2. The contact surface between the side roll 24A and the split roll 24B, the contact surface between the split roll 24C and the split roll 24D, and the contact surface between the split roll 24E and the side roll 24A may be diffusion-bonded. Even in that case,
Side roll 24A, split roll 24B, split roll 2
4C and the split roll 24D, and the split roll 24E and the side roll 24A are unitized, and can be replaced for each unit. Alternatively, only the contact surface between the split rolls 24C and 24D can be diffusion bonded. In this case, the split roll 24C and the split roll 24
This is because the highest pressure due to the material flow occurs at the bending portion located at the boundary with D.

However, when rolling is performed in a direction in which the material flows toward both ends and the center of each W-shaped fin 2, deformation due to the material flow is caused on both side edges of the plate material T. Therefore, it is preferable to perform the rolling in the direction shown in FIG. 11, that is, the direction in which the material does not flow toward the both side edges of the plate material T, since the subsequent welding may be hindered. . The same applies to the case where the fin 2 is formed in a V-shape instead of a W-shape, or in the case where the fin 2 is formed in a “VVV” shape that is bent five times.

On the outer peripheral surfaces of the split rolls 24B and 24E,
In the vicinity of the side roll 24A, the side roll 24
A conical surface whose outer diameter gradually decreases toward the side A may be formed. In this case, the strip material T in the groove 4 after the rolling is performed.
Is formed so as to gradually increase toward both side edges of the plate material T. In this case, further, in the same portion, the depth of the rolling groove 25 of the divided rolls 24B and 24E is formed so as to gradually decrease toward the side roll 24A, and the height of the fin 2 formed on the plate material T is increased. May be adjusted to decrease as it approaches the weld. Further, the outer peripheral surface of the side roll 24A may be a tapered surface whose outer diameter decreases outward in the axial direction, so that the thickness of the plate material at the finless portion 6 is reduced within the groove 4. It may be set to be larger than the thickness of the strip material. In each of these cases, it is possible to increase the strength near the weld.

The angle formed by the fin rolling groove 25 with respect to the circumferential direction of the roll is a value determined according to the characteristics required for the heat transfer tube P, and is not limited in the present invention. Is preferably about 5 to 25 °. The depth of the fin rolling groove 25 is not limited, but is generally about 0.1 to 0.3 mm. The higher the fins 2, the greater the rolling reduction, so the material flow of the strip material tends to be remarkable, and the effect of the present invention is more likely to be exhibited accordingly. The cross-sectional shape of the fin rolling groove 25 is not limited, and may be a triangular cross-section (the tip may be rounded or pointed), or may be trapezoidal or semi-circular. .

Fin Roll 24 and Receiving Roll 2
As shown in FIG. 1, the strip material T rolled by 6 is to be gradually rolled into a tube through a pair of rolls 28 and a plurality of forming rolls 30 arranged in pairs, and to be abutted by a rolling separator 32. The gap between both end edges is kept constant, and is passed through the induction heating coil 34 to heat both side edges. In this embodiment, the plate material T is rounded so that the fins 2 are located on the inner peripheral surface side.
Conversely, the plate member T can be rounded so that the fin 2 is located on the outer peripheral surface side (the same applies to other embodiments described later). The plate material T which has been formed into a tube and heated is passed through a pair of squeeze rolls 36, and is pressed from both sides so that both heated side edges abut and are welded.
Since a bead (upset) protruding by plastic flow is formed on the outer peripheral surface of the heat transfer tube P thus welded, a bead cutter 38 for cutting the bead is provided.

The heat transfer tube P from which the beads have been cut is placed in the cooling tank 40.
After passing through the sizing rolls 42, the sizing rolls 42 are arranged in a plurality of pairs and are reduced to a predetermined outer diameter. Further, the heat transfer tube P having a reduced diameter is wound up by the rough coiler 44.

Although the dimensions of the grooved heat transfer tube P are not limited in the present invention, when the values of a general heat transfer tube are exemplified, the outer diameter is about 3 to 15 mm, and the thickness of the tube wall in the groove 4 is Is about 0.15 to 0.5 mm. The material of the grooved heat transfer tube P is not limited, and various materials such as copper, copper alloy, aluminum, aluminum alloy, and steel can be used. Preferably, copper or copper alloy is used. Copper oxide (for example, JIS1220 alloy) and oxygen-free copper are suitable.

According to the grooved heat transfer tube manufacturing apparatus having the above-described structure, the split rolls 24B and 24C and the split rolls 24D and 24E are respectively diffusion-bonded, so that the fins are formed at the interface between each pair of split rolls. Rolling groove 25
Even the end faces of the respective groove partition walls butted by the bent portions are integrally connected. Thus, when the line speed of the rolling is increased, when the tall fins are rolled, and / or with the rotation of the fin rolling rolls 24, the side on which the individual fins are finally formed on the plate material. In the above, even when an excessive pressure is applied to the bent portion of the fin rolling groove 25 due to the material flow, the end of the groove partition wall butted by the bent portion is less likely to be lost, and the life of the fin rolling roll can be extended. it can.

[Second Embodiment] FIG. 4 shows a fin roll 24 used in an apparatus for manufacturing a grooved heat transfer tube according to a second embodiment of the present invention. This embodiment uses a split roll 24
B and 24C and the split rolls 24D and 24E are common to the first embodiment in that they are diffusion bonded to each other.
The diameters of the outer peripheral surfaces of the split rolls 24B to 24E are not constant, and each of the split rolls 24B to 24E is located near the mating surface between the split roll 24B and the split roll 24C and near the mating surface between the split rolls 24D and 24E. 24
The difference is that the outer diameter of E is relatively reduced. Therefore, two concave portions 46 are formed on the outer peripheral surface of the fin rolling roll 24 over the entire circumference.

The mating surface of the split rolls 24B and 24C, and the split rolls 24D and 24E
When the fins 2 are rolled onto the sheet material T by the fin rolling rolls 24, the fins 2 correspond to the places where the individual fins 2 are finally formed, and the material flow toward these mating surfaces appear. That is, the vicinity of these mating surfaces is
In FIG. 11, this corresponds to the region A on the fin rolling end side.

If the direction of the axis of the fin rolls 24 is reversed, the material flows toward both ends and the center of each W-shaped fin 2. As described above, the contact surface between the side roll 24A and the split roll 24B, the contact surface between the split roll 24C and the split roll 24D, and the contact surface between the split roll 24E and the side roll 24A are respectively diffusion bonded. Alternatively, after only the contact surface between the split roll 24C and the split roll 24D is diffusion-bonded, the side roll 24A and the split roll 2
4B, near the mating surface of the split rolls 24C and 24D, and near the split roll 24.
In the vicinity of the mating surface between E and the side roll 24A,
The outer diameter of each of the split rolls 24B to 24E is relatively reduced, and three concave portions 46 are formed on the outer peripheral surface of the fin roll 24.
May be formed.

The cross section of the concave portion 46 has a wide V
The shape may be a letter shape or a rounded shape. When the fin 2 is rolled by the fin rolling roll 24, the width W1 and the depth D1 of the concave portion 46 are determined by the mating surface of the split rolls 24B and 24C and the alignment of the split rolls 24D and 24E. The material flow generated toward the surface should be set in such a manner that it can be absorbed in these recesses 46 and that the fins 2 do not locally rise in the region corresponding to the mating surface.

The width W1 and the depth D1 of the concave portion 46 satisfying this condition are not limited, but in the case of a general grooved heat transfer tube, the depth D1 is 3 to 20% of the thickness of the plate material T. Is more preferable, and more preferably about 5 to 10%.
If the depth D1 of the concave portion 46 is too small, the phenomenon that the fin 2 becomes high in the region on the fin rolling end side cannot be prevented, and the life of the fin rolling roll 24 is shortened. Conversely, if the depth D1 of the concave portion 46 is too large, the fin 2 becomes too low at the corresponding portion, which affects the heat exchange performance. Also, the recess 46
Is preferably 3% or more of the width of the plate material T. If it is too small, the effect of preventing the fin 2 from becoming high in the region on the fin rolling end side is reduced. Recess 4
6 may be equal to the width of two divided rolls. In this case, the outer peripheral surface of each split roll is inclined over the entire surface.

In this embodiment, the fin 2, the groove 4, and the finless portion 6 are formed by the fin rolls 24 as shown in FIG. In this rolling process, the material pressed down to form the groove 4 is moved from the fin rolling start side to the fin rolling end side in the fin rolling groove 2.
5, a concave portion 46 is formed in the fin rolling end portion of the outer peripheral surface of the fin rolling roll 24, and the processing amount is reduced by that amount, so that the material flow is absorbed by these portions, and the fin rolling is performed. Excessive metal material can be prevented from entering the depth of the groove 25. Therefore, the height of the fin 2 in the region corresponding to the concave portion 46 does not become excessively large.

At a position corresponding to the concave portion 46 of the fin roll 24, a slight convex portion 50 may be formed on the surface of the plate material T as shown in FIG. It is desirable that the thickness be 75% or less of the thickness of the strip material T before rolling. This is because if it is too large, this part becomes hard and roll forming becomes difficult.

Other configurations may be the same as in the first embodiment. According to the second embodiment, the fin rolls 24
When the fins 2 and the grooves 4 are rolled, the material pressed down to form the grooves 4 flows along the fin rolling grooves 25 from the fin rolling start side to the fin rolling end side. Also, the material flow can be absorbed by the concave portion 46 formed on the outer peripheral surface of the fin rolling roll 24 on the fin rolling end side portion, and it is possible to prevent excessive metal material from entering the fin rolling groove 25. . Therefore, the height of the fin 2 does not become excessively high in a region corresponding to the concave portion 46, and interference between the fin 2 and the edge of the fin rolling groove 25 can be prevented, damage to the edge is suppressed, and the split roll 24B ~
The service life of the fin roll 24 can be further extended in synergy with the diffusion bonding of 24E.

Third Embodiment Next, FIG. 6 shows a fin roll 24 and a receiving roll 26 according to a third embodiment of the present invention. The other parts are the same as in the first embodiment, and a description thereof will be omitted.

In this embodiment, the fin rolls 24
The concave portion 46 is not formed in the receiving roll 2
6, the mating surface of the split roll 24B and the split roll 24C, and the split roll 24D and the split roll 24
Two concave portions 52 are formed over the entire circumference at positions facing the mating surfaces with E, respectively. Width W2 of recess 52
The depth D2 is set in the same manner as the recess 46 of the second embodiment.

According to such an embodiment, when the fin 2 and the groove 4 are rolled by the fin rolling roll 24, a part of the plate material T is elastically deformed into the concave portion 52 and escapes. The processing amount in the portion facing 52 is relatively reduced. Therefore, even if the material pressed down when forming the groove 4 flows from the fin rolling start side to the fin rolling end side, the material flow can be absorbed by the concave portion 52, and the fins 2 are formed in these regions. Excessive height is prevented, and fins 2 having a substantially uniform height as shown in FIG. 7 can be rolled. Therefore, the interference between the fin 2 and the edge of the fin rolling groove 25 is reduced, the edge can be prevented from being damaged by the interference, and the pair of the split rolls 24B to 24E is diffused and joined together, and the The service life of the rolls 24 can be further extended.

[Fourth Embodiment] FIG. 8 shows a main part of a fourth embodiment of the present invention. In this embodiment, instead of changing the shape of the fin rolling roll 24 or the receiving roll 26, the former stage of the fin rolling process shown in FIGS. 2 and 3, that is, the holding roll 22 and the fin rolling roll in FIG. 24, a rolling mechanism for the strip T shown in FIG. 8 is provided to adjust the thickness of the strip T.

The rolling mechanism of this embodiment includes a grooving roll 54 and a receiving roll 60 which are arranged to face each other. The outer peripheral surface of the receiving roll 60 is flat, while the outer peripheral surface of the grooving roll 54 is In each of the first and second embodiments, a gentle protrusion 56 is formed at a position corresponding to a mating surface between the split rolls 24B and 24C and a mating surface between the split rolls 24D and 24E. The width W3 and the height D3 of these ridges 56 are not limited, but may be set in the same manner as the width W1 and the depth D1 of the recess 46 in the second embodiment.

In this embodiment, as shown in FIG. 1, the strip material T is continuously fed out from the uncoiler 20, and the fed strip material T is received by a grooved roll 54 via a pair of holding rolls 22. It passes between rolls 60 (not shown in FIG. 1). Then, a pair of shallow concave grooves 58 are formed on the surface of the plate member T by being pressed down by the protrusions 56.

Next, the plate material T having the concave groove 58 formed on the surface thereof is passed between the fin roll 24 and the receiving roll 26 shown in FIGS. W-shaped fins 2, grooves 4, and finless portions 6 (FIG. 1)
1). At this time, in the vicinity of the fin rolling end point, the concave groove 58 is formed in the strip material T in advance, and the processing amount in the portion facing the concave groove 58 is relatively reduced. Even if the material pressed down by 24 flows from the fin rolling start side to the fin rolling end side, the material flow can be absorbed by the concave grooves 58, and the fins 2 become excessively high in these regions. It is possible to roll the fins 2 which are prevented and have a substantially uniform height.
Therefore, the interference between the fin 2 and the edge of the fin rolling groove 25 is reduced, the edge can be prevented from being damaged by the interference, and the pair of the split rolls 24B to 24E is diffused and joined together, and the The service life of the rolls 24 can be further extended.

In another embodiment of the present invention,
As shown in FIG. 9, the width of the protrusion 56 may be increased to about half the width of the plate material T.

Although a plurality of embodiments have been described, the present invention is not limited to only the above embodiments, and the features of each embodiment may be appropriately combined. For example, the concave portion 46 may be formed on the fin rolling roll 24 and the concave portion 52 may be formed on the receiving roll 26 at the same time, or a plate material thickness adjusting mechanism may be combined. If necessary, the side rolls 24A may be integrally diffusion-bonded with the split rolls 24B and 24E.

[0052]

As described above, in the grooved heat transfer tube manufacturing apparatus and the fin roll according to the present invention, each of the split rolls, that is, the fin roll is rotated, and the individual fin rolls are rotated on the sheet material. Since the end faces on the side where the fins are formed last are diffusion bonded to each other, the end faces of the groove partition walls butted at the bent portion of the fin rolling groove are also integrally connected. Thus, even when the rolling line speed is increased, when tall fins are rolled, and / or when excessive pressure is applied to the bending portion of the fin rolling groove at the end of the material flow, the bending portion can be formed. The ends of the groove partition walls butted against each other are less likely to be lost, and the life of the fin rolling roll can be extended.

In the case where side rolls having a smooth surface are arranged coaxially on both sides of the fin roll, and these side rolls can be replaced with other side rolls having different outer diameters, welding is performed. It can easily respond to changes in conditions.

If the outer diameter of the fin rolling roll and / or the receiving roll is relatively reduced at the position at the end of the material flow, the fins may be excessive due to the bias of the material. Can be prevented. Therefore, the interference between the fin and the edge of the fin rolling groove is reduced, the edge is prevented from being damaged by the interference, and the service life of the fin rolling roll is further extended in synergy with the effect of diffusion bonding of the divided rolls to each other. It is possible.

Further, a thickness adjusting mechanism for rolling the plate material and partially adjusting its thickness is provided at a stage preceding the fin rolling roll, and the plate material is disposed at a position at the end of the material flow. When the thickness is reduced, it is possible to prevent a phenomenon that the fins become excessively high due to the bias of the material. Therefore, the interference between the fin and the edge of the fin rolling groove is reduced, the edge is prevented from being damaged by the interference, and the service life of the fin rolling roll is further extended in synergy with the effect of diffusion bonding of the divided rolls to each other. It is possible.

[Brief description of the drawings]

FIG. 1 is a side view showing a first embodiment of an apparatus for manufacturing a grooved heat transfer tube according to the present invention.

FIG. 2 is a front view showing the vicinity of a fin roll of the manufacturing apparatus.

FIG. 3 is a sectional view of a fin roll of the manufacturing apparatus.

FIG. 4 is a front view showing the vicinity of a fin roll of a second embodiment.

FIG. 5 is an enlarged cross-sectional view of a sheet material rolled by the manufacturing apparatus.

FIG. 6 is a front view showing the vicinity of a fin roll of a third embodiment.

FIG. 7 is an enlarged cross-sectional view of a sheet material rolled by the manufacturing apparatus.

FIG. 8 is a front view showing a plate member thickness adjusting mechanism according to a fourth embodiment.

FIG. 9 is a front view showing a modified example of the plate material thickness adjusting mechanism.

FIG. 10 is a partially developed plan view showing an example of a grooved heat transfer tube.

FIG. 11 is a plan view of a rolling process of a sheet material showing a conventional problem.

[Explanation of symbols]

 Reference Signs List 1, heat transfer tube with P groove 2 fin 4 groove 6 both side edges (no fin portion) 24 fin roll 24A side roll 24B to 24E division roll 25 fin roll groove 26 receiving roll 30 forming roll 34 induction heating coil (welding Part of mechanism) 36 Squeeze roll (part of welding mechanism) 46, 52 Concave part 54 Grooving roll 60 Receiving roll 56 Ridge part 58 Groove

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F28F 1/40 F28F 1/40 E

Claims (6)

[Claims] 1. A fin rolling roll and a receiving roll for rolling a fin on one surface of the plate member by rolling with a metal plate member interposed therebetween, and a plate member formed with the fins, A plurality of forming rolls for forming into a tubular shape so that the fins are located on the inner circumferential side or the outer circumferential side, and welding for heating and butt-welding both end edges of the plate-shaped strip material formed into a tubular shape. A fin roll, the fin roll has a plurality of split rolls that are formed coaxially with a fin roll formed on the outer peripheral surface, and these split rolls are used to rotate the fin roll. A device for manufacturing a grooved heat transfer tube, characterized in that the end faces on the side where individual fins are finally formed on the plate material are diffusion bonded to each other. 2. The grooved heat transfer tube manufacturing apparatus according to claim 1, wherein adjacent split rolls have different angles between the fin rolling grooves formed therein and the roll circumferential direction. . 3. Side rolls having smooth surfaces are arranged coaxially on both sides of the fin roll, and these side rolls can be replaced with other side rolls having different outer diameters. The apparatus for manufacturing a grooved heat transfer tube according to claim 1 or 2. 4. An outer diameter of the fin roll and / or the receiving roll is such that the outer diameter of the fin roll is opposite to a region where individual fins are finally formed on the strip with the rotation of the fin roll. The apparatus for manufacturing a grooved heat transfer tube according to any one of claims 1 to 3, wherein a diameter of the groove is relatively reduced in a region near the joining surface. 5. A thickness adjusting mechanism for rolling the plate material and partially adjusting the thickness thereof before the fin rolling roll, the thickness adjusting mechanism comprising: The rolling roll has a function of relatively reducing the thickness of the plate material in a region near the diffusion bonding surface where individual fins are formed last on the plate material. 4. The manufacturing apparatus for a grooved heat transfer tube according to any one of the above items 4. 6. A fin rolling groove is formed on an outer peripheral surface, and a plurality of divided rolls are provided coaxially with each other, and each of the divided rolls is diffusion-bonded to one side only. Fin rolling roll.