JPH11173470A - Connection pipe in metallic piping system, connection structure in metallic piping system employing the connection pipe, and manufacture of connection pipe in metallic piping system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To connect piping members with no flux used in a metallic piping system such as a compressor for an air-conditioner where a compressor body acting as a piping member made of iron is connected with a heat transfer pipe formed out of copper-made piping. SOLUTION: A connection pipe 3 is manufactured, in which clad material 7 where its inner circumferential part 7A is made of copper, and its outer circumferential part 7B is made of iron, is formed into a pipe shape by rolling in a plate shaped and clad material where one side surface is made of copper, and the other side surface is made of iron, and joining both the ends of the clad material by electric resistance welding. A compressor body is joined with the outer circumferential part 7B of the connection pipe 3 using the connection pipe 3, and concurrently, a heat transfer pipe 6 is joined with the inner circumferential part 7B of the connection pipe 3, so that the body is thereby connected with the heat transfer pipe 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection pipe of a metal piping system used for connecting an iron compressor body and a copper heat transfer tube in a compressor of an air conditioner, for example, and a metal piping system using the connection pipe. And a method for manufacturing the connection pipe of the metal piping system.

[0002]

2. Description of the Related Art In a metal pipe system such as a compressor in an air conditioner such as an air conditioner, a heat transfer pipe as a pipe member for circulating a heat medium for air conditioning is made of copper, while a compressor for condensing the heat medium is used. The main body as a piping member is made of iron. Therefore, at the connecting portion between the heat transfer tube and the compressor main body, the copper member and the iron member must be hermetically joined. And
Conventionally, such joining between a copper member and an iron member is performed by brazing using a flux. Here, the use of the flux at the time of brazing as described above, if the flux is not used, voids are generated and the wettability of the brazing material is deteriorated, which may cause leakage at the connection part. Because there is.

[0003]

However, in the brazing using such a flux, if the flux remains at the connection portion after the brazing process, the remaining flux activates the surface of the base material, that is, Since the compressor main body and the heat transfer tube are eroded and corroded, there is a possibility that the heat medium leaks out due to holes in the compressor main body and the heat transfer tube. Therefore, in the process of manufacturing a compressor of an air conditioner as described above, after the heat transfer tube is brazed to the compressor body, first, the remaining flux is washed, and then the connection between the compressor body and the heat transfer tube is painted. After the application, the compressor itself must be assembled, it takes a lot of time and labor to assemble this compressor, and it is necessary to prepare cleaning equipment for flux cleaning. There was a problem.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an air conditioner in which a compressor body, which is an iron pipe member, and a heat transfer pipe, which is a copper pipe member, are connected. It is an object of the present invention to connect these piping members without using flux in a metal piping system such as a compressor.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to achieve such an object, the present invention provides an electroconductive cladding material having an inner peripheral portion made of copper and an outer peripheral portion made of iron. A connection pipe of a metal piping system characterized by being formed into a tubular shape by sewing. However, by joining the pipe members to each other via such a connection pipe, according to the present invention, at the joint with the iron pipe member, the outer peripheral portion of the connection pipe is connected to the copper pipe member. At the joint, the inner peripheral portion of the connection pipe can be joined to each piping member without using a flux, and there is no need to wash the flux thereafter.

Here, in the connection structure of a metal pipe system using such a connection pipe, the outer peripheral portion of the connection pipe is joined to the iron pipe member, or the connection section is connected to the copper pipe member. The inner circumference of the pipe can be joined, or the outer circumference of the connection pipe can be joined to the iron pipe member, and the inner circumference of the connection pipe can be joined to the copper pipe member. In any case, by using the connection pipe according to the present invention, it is not necessary to use a flux at the time of joining. In particular, when the metal piping system is a compressor for an air conditioner as described above, the iron piping member is used as a compressor body, or the copper piping member is used as a heat transfer tube, thereby manufacturing the compressor. In the process, the cleaning process for removing the flux is omitted, so that the time and labor required for assembling the flux, the cost required for installing the cleaning equipment, and the like can be reduced.

On the other hand, when manufacturing a connecting pipe having the above-described structure, for example, a copper pipe is inserted into an inner peripheral portion of an iron pipe, and both are integrally drawn using a floating plug or the like. From the beginning, it is also conceivable to manufacture the connection pipe as a clad pipe in which an iron outer circumference and a copper inner circumference are joined, but in such a manufacturing method, at least one of the iron pipe and the copper pipe is bent. If this is the case, it becomes difficult to insert and insert the pipes, and oil injected at the time of drawing may enter between the pipes and cause poor joining of the inner and outer peripheral portions, and furthermore, the clearance between the pipes is large. There is also a possibility that the clad tube may be broken or the wall thickness may be unbalanced due to the difference in the elongation percentage between iron and copper. Therefore, in order to avoid such a problem, a plate-shaped clad material having one surface made of copper and the other surface made of iron is used. It may be rounded so as to be on the peripheral side, the both side edges thereof are opposed to each other, and then these two side edges are butted and joined by electric welding to form a tube.

[0008]

1 to 3 show one embodiment of a connection pipe of a metal piping system and a connection structure of the metal piping system using the connection pipe of the present invention. The metal piping system in the present embodiment is a compressor of an air conditioner as described above. The compressor 1 includes a drive motor and a compressor (not shown) inside an iron main body 2 which is a closed-end cylindrical airtight container. At the same time, the connection ports 4 and 5 made of the connection pipe 3 of the present embodiment are provided in the center of the lid portion and the body peripheral portion of the main body 2, respectively.
5 is connected to heat transfer tubes 6 and 6 made of copper. However, the connection port 4 provided in the lid of the main body 2
Is a discharge port serving as an outlet of the heat medium from the compressor 1. At the connection port 4, the connection pipe 3 is formed in a straight tubular shape, while the connection port 5 provided on the body periphery of the main body 2 is
A connection port serving as an inlet of a heat medium to the compressor 1. At the connection port 5, the connection pipe 3 is bent in an L shape.

As shown in FIGS. 2 and 3, the connection pipes 3 and 3 are made of a clad material 7 whose inner peripheral portion 7A is made of copper and whose outer peripheral portion 7B is made of iron. It is configured to be formed in a tubular shape. However,
2 and 3 show the connection port 4 serving as a heat medium discharge port.

Here, as shown in FIG. 2, the connecting pipe 3 is welded to the iron main body 2 of the compressor 1 by abutting the iron outer peripheral portion 7B of the clad material 7 on the main body 2. On the other hand, the heat transfer tube 6 made of copper is joined to the copper heat transfer tube 6 by brazing after fitting the heat transfer tube 6 to the copper inner peripheral portion 7A to some extent. In the figure, reference numeral 8 denotes a joint between the main body 2 and the outer peripheral portion 7B of the connection pipe 3, and reference numeral 9 denotes a joint between the heat transfer tube 6 and the inner peripheral portion 7A of the connection pipe 3. This is the junction. Further, in brazing the connection pipe 3 and the heat transfer pipe 6, it is preferable to use a phosphor copper braze as a brazing material, and by adopting such a configuration, the phosphor component contained in the phosphor copper braze can be used. Since activation of the base material surface is promoted, reliable bonding can be obtained.

Further, when connecting the main body 2 of the compressor 1 and the heat transfer pipe 6 via the connecting pipe 3 as described above, the connecting pipe 3 and the main body 2 are joined first, and then the connecting pipe 3 is connected. And the heat transfer tube 6 are desirably joined. This is because the joining temperature by welding when joining the iron main body 2 and the outer peripheral portion 7B of the connecting pipe 3 is better when the copper heat transfer tube 6 and the inner peripheral portion 7A of the connecting pipe 3 are joined. Since the connecting temperature is higher than the joining temperature due to the joining, when the connecting pipe 3 and the heat transfer pipe 6 are joined first, the heat of the welding at the time of joining the connecting pipe 3 and the main body 2 subsequently causes the connecting pipe 3 to be joined. This is because there is a possibility that the joint 9 between the heat transfer tube 6 and the heat transfer tube 6 is softened and the joint strength is impaired.

On the other hand, in the connection pipe 3 of the present embodiment,
The thickness of the inner peripheral portion 7A and the outer peripheral portion 7B of the clad material 7 are set to be equal to each other, and the bonding strength between the connecting pipe 3 and the main body 2 and the bonding between the connecting pipe 3 and the heat transfer pipe 6 are set. The strength is designed to be substantially equal. However, in a case where the tubular clad material 7 can be further deformed like the connection pipe 3 at the connection port 5 which is bent into an L-shape, the thickness of the copper inner peripheral portion 7A which is rich in ductility is increased. The diameter of the outer peripheral portion 7B may be made larger than that of the outer peripheral portion 7B to make it easier to deform. On the other hand, when high strength is required for the connection pipe 3 itself, the thickness of the outer peripheral portion 7B made of iron is reduced. It may be set to be larger than the inner peripheral portion 7A.

Next, FIG. 4 illustrates an embodiment of a manufacturing method for manufacturing the connecting pipe 3 as described above. In the present embodiment, when manufacturing the connecting pipe 3, first, a copper plate material 10 and an iron plate material 11 are bonded by hot rolling using a rolling roll 12 as shown in FIG. Plate-like cladding material 13 whose surface 13A is made of copper and the other surface 13B is made of iron
To manufacture. Then, the plate-shaped clad material 13 is rolled in the width direction by forming rolls 14 so that the one surface 13A faces the inner peripheral side, and formed into a C-shaped cross section with both side edges facing each other. I do.

Then, the clad material 13 thus rounded is passed through an induction heating coil 16 to heat the side edges by induction current, while keeping a constant gap between the both side edges by a separator 15. , And squeeze roll 17
By pressing from both sides through the gap, the heated side edges are butt-welded and welded, that is, by electric resistance sewing, from the clad material 7 in which the inner peripheral portion 7A is made of copper and the outer peripheral portion 7B is made of iron. Into a substantially circular connecting pipe 3. Further, since the bead is formed on the outer peripheral portion 7B of the thus formed connecting pipe 3 by the melt protruding from the abutting both side edges, the bead is cut by a bead cutter 18 or the like. Next, the connecting pipe 3 is cut into a predetermined length and used for connecting the main body 2 of the compressor 1 and the heat transfer pipe 6 as described above. In addition, by being formed into a tubular shape by electric resistance in this way, the clad material 7 constituting the connection pipe 3 is welded to the welded portions of both side edges of the rounded clad material 13 as shown in FIG. As shown, a weld 7C is formed.

However, according to the connecting pipe 3 manufactured in the above-described embodiment, the clad material 7 is formed as described above.
By joining the copper inner peripheral portion 7A to the copper heat transfer tube 6 and joining the iron outer peripheral portion 7B to the iron main body 2, the iron piping of the metal piping system such as the compressor 1 can be used without using flux. The main body 2 as a member and the heat transfer tube 6 as a copper piping member can be connected. Therefore, since the base material does not corrode due to the residual flux, it is not necessary to clean the joints 4 and 5 after joining in order to remove the residual flux, and the copper piping in such a metal piping system is not required. The connection between the member and the iron pipe member can be reliably and easily performed.

For this reason, in the metal piping system such as the compressor 1 having the connection structure using the connection pipe 3, the conventional flux cleaning step can be omitted in the manufacturing process. The time and labor required for the process can be reduced.
It is possible to improve the working efficiency up to assembling, and it is not necessary to provide a cleaning facility for cleaning the flux, so that the cost required for installing the cleaning facility can be reduced. Therefore, as a result, according to the connection structure of the metal piping system of the embodiment, it is possible to provide the metal piping system like the compressor 1 at a lower cost.

In the connection structure of the metal piping system of the present embodiment, a compressor 1 such as an air conditioner is provided as the metal piping system, in which an iron body 2 and a copper heat transfer tube 6 are connected by a connection tube 3. Although the case has been described, as a connection structure of the metal piping system using the connection pipe 3, a connection structure of only the main body 2 of the compressor 1 in which the connection pipe 3 is connected to the connection port 4 or the connection port 5, It is also possible to adopt a joining structure such as a heat transfer tube 6 in which the connecting tube 3 is joined to the end. In particular, the iron body 2 to which the connecting pipe 3 is joined
According to the joint structure as described above, the connection pipe 3 is made of a copper heat transfer pipe 6.
Before being joined to the main body 2, it is in a state of being joined to the iron body 2, so that the influence of heat due to welding between irons as described above can be reliably prevented.

In the above-described embodiment, the compressor 1 such as the air conditioner described above is described as a metal piping system having a connection structure using the connection pipe 3, but the connection pipe 3 and the compressor 1 are used. The connection structure can, of course, be applied to other metal piping systems that connect an iron piping member and a copper piping member, and can be used, for example, when simply connecting an iron pipe and a copper pipe. is there. Further, in the above-described embodiment, the case has been described where the connection ports 4 and 5 between the main body 2 of the compressor 1 and the heat transfer tubes 6 are constituted by the connection pipe 3. However, for example, the connection ports are formed by subjecting the main body 2 to burring. Of course, it is also possible to form an integral connection with the main body 2 by welding an iron connection pipe or the like, and to connect the heat transfer pipe 6 to the connection port via the connection pipe 3.

On the other hand, in the method of manufacturing the connection pipe 3 according to the above-described embodiment, the plate-like clad material 1 in which one surface 13A is made of copper and the other surface 13B is made of iron.
3 is rounded so that the one surface 13A is on the inner peripheral side, and the two side edges are opposed to each other. Is formed. That is, since the clad material 13 in which copper and iron are bonded together is originally formed into a tubular shape, for example, when the copper tube is inserted into the inner periphery of the iron tube and drawn, the iron and copper are bent by bending or oil. Clad material in which iron and copper are joined at a specified thickness without disturbing the joining of the steel and without causing breakage or uneven thickness due to the difference in elongation between iron and copper during drawing 7 can be reliably manufactured.

In FIG. 4, for the sake of explanation, the process from the production of the plate-shaped clad material 13 by the rolling roll 12 to the cutting of the connection pipe 3 subjected to electric resistance welding is performed continuously. If necessary, each step may be a separate step without employing a simple configuration, and the clad material 13 cut to a predetermined length from the beginning is individually rolled and subjected to electric resistance welding to manufacture the connection pipe 3. It may be. Furthermore, in the manufacturing method of the above embodiment, when manufacturing the flat clad material 13, the copper plate material 10 and the iron plate material 11 are bonded to each other by a rolling method by hot rolling using the roll 12. Although the connecting pipe 3 is used, the connecting pipe 3 can of course be manufactured using the clad material 13 manufactured by another method such as an explosion method.

[0021]

As described above, according to the present invention,
It is possible to reliably and easily connect an iron pipe member and a copper pipe member without using a flux. In a manufacturing process of a metal pipe system such as a compressor having the connection structure of the pipe members, flux cleaning is performed. Time and labor or cleaning equipment
It is possible to improve work efficiency and reduce equipment costs.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a connection structure for a metal piping system of the present invention.

FIG. 2 is an enlarged cross-sectional view around a connection port 4 of the embodiment shown in FIG. 1 and shows a connection pipe 3 of one embodiment of the present invention.

FIG. 3 is a sectional view taken along the line ZZ in FIG. 2;

FIG. 4 is a diagram illustrating one embodiment of a method for manufacturing a connection pipe of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor (metal piping system) 2 Main body of compressor 1 (iron piping member) 3 Connection pipe 4, 5 Connection port 6 Heat transfer pipe (copper piping member) 7, 13 Clad material 7A Copper inner peripheral part of clad material 7 7B Iron outer peripheral portion of clad material 7 8, 9 Joint 13A One surface of copper of clad material 13 13B The other iron surface of clad material 13

Claims (8)

[Claims] 1. A connecting pipe for a metal piping system, wherein a cladding material having an inner peripheral portion made of copper and an outer peripheral portion made of iron is formed into a tubular shape by electric resistance welding. 2. A connection structure of a metal piping system using the connection pipe of the metal piping system according to claim 1, wherein an outer peripheral portion of the connection pipe is joined to an iron pipe member. Metal piping system connection structure. 3. The metal pipe connection structure according to claim 2, wherein the iron pipe member is a compressor body of an air conditioner. 4. A connection structure of a metal piping system using the connection pipe of the metal piping system according to claim 1, wherein an inner peripheral portion of the connection pipe is joined to a copper piping member. Connection structure of metal piping system. 5. The connection structure for a metal piping system according to claim 4, wherein the copper piping member is a heat transfer tube of a compressor of an air conditioner. 6. A connection structure for a metal pipe system using the connection pipe for a metal pipe system according to claim 1, wherein an outer peripheral portion of the connection pipe is joined to an iron pipe member, and the connection pipe is connected to the iron pipe member. A metal pipe connection structure, wherein an inner peripheral portion of the metal pipe is joined to a copper pipe member. 7. The metal piping system according to claim 6, wherein the iron pipe member is a main body of a compressor of an air conditioner, and the copper pipe member is a heat transfer tube of the compressor. Connection structure. 8. The method for manufacturing a connection pipe for a metal piping system according to claim 1, wherein the plate-shaped clad material having one surface side made of copper and the other surface side made of iron is provided. The metal pipe connection pipe is characterized in that it is rounded so that its surface is on the inner peripheral side and its both side edges are opposed to each other. Manufacturing method.