JP3636945B2 - Refrigerant piping - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigerant pipe, and more particularly, to a refrigerant pipe provided with a deoxygenation device for removing oxygen from the inside of a pipe around a portion to be brazed.
[0002]
[Prior art]
One method for joining refrigerant pipes in air conditioners is brazing. Brazing is a method in which a copper pipe and a brazing material are heated by an oxygen / acetylene flame, and the pipe is joined by a molten brazing material. At this time, the refrigerant pipe is exposed to a high-temperature flame, and an oxide is generated. Oxides generated in the piping contaminate the refrigerant circuit and become a major factor that hinders the operation of the air conditioner.
[0003]
Thus, as a conventional method for suppressing oxide formation during brazing, for example, a non-oxidative brazing method and an oxide filtration method by attaching a pipe strainer can be cited.
[0004]
The oxide filtration method by attaching a pipe strainer is not a fundamental technique because it only attaches a strainer to a refrigerant pipe and filters the oxide, does not suppress oxide formation itself.
[0005]
Therefore, a non-oxidative brazing method has been conventionally effective as a method for suppressing oxide generation. An example of the non-oxidation brazing method is shown in FIG.
[0006]
In the non-oxidizing brazing method, first, the expanded portion 3 formed at one end of the connecting pipe 2 is fitted into the connected pipe 1. Next, the other end of the connection pipe 2 and one end of the injection pipe 5 are fixed with a close fitting 4 such as a tape, and the other end of the injection pipe 5 is filled with an inert gas such as nitrogen via a valve 6. The hose 7 is connected to the supply port of the cylinder 7 by a hose.
[0007]
Next, an inert gas is supplied from the cylinder 7 into the connection pipe 2 and the connected pipe 1 via the valve 6 and the injection pipe 5. Thereby, the air containing oxygen in the vicinity of the brazed joint between the connected pipe 1 and the expanded pipe portion 3 is pushed away by the inert gas and removed. Accordingly, oxygen around the brazed joint portion is replaced with an inert gas, and therefore, when the pipe expansion section 3 is heated by a burner or the like to braze the pipe 1 to be joined and the pipe 2 to be joined, oxide generation is caused. Can be suppressed.
[0008]
[Problems to be solved by the invention]
However, in order to remove oxygen in the refrigerant pipe, a device for introducing an inert gas into the pipe in advance is required, which increases the cost. In addition, there is a problem that it is difficult for a third party to visually determine whether or not to replace with an inert gas, and the brazing joining work becomes complicated.
[0009]
The present invention has been made in order to solve the above-described problems, and removes oxygen in a pipe before brazing work and easily determines whether or not oxygen is removed before brazing work in appearance. It aims at providing refrigerant piping provided with.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the refrigerant pipe according to the present invention has the following characteristics.
[0011]
(1) In a refrigerant pipe formed by brazing an expanded portion of a connection pipe to a connected pipe, a deoxygenation device for sucking and removing oxygen in the pipe at the time of brazing is provided to the connected pipe.
[0012]
(2) In the refrigerant pipe formed by brazing the expanded portion of the connection pipe to the connected pipe, a deoxygenation device is provided to suck and remove oxygen in the pipe at the time of brazing to the connected pipe and the connection pipe. It has been.
[0013]
According to the refrigerant pipes of the above (1) and (2), the oxygen in the pipe can be removed before the brazing and joining work, and the conventional equipment for flowing an inert gas into the pipe is not required, which reduces the cost. Can be reduced.
[0014]
(3) In the refrigerant pipe according to the above (1) or (2), the deoxygenation device includes at least one of the connected pipe or the connected pipe and a material that can be oxidized outside the connected pipe. Two deoxygenation containers and a hole for communicating the pipe and the deoxygenation container are provided.
[0015]
Therefore, by burning the oxidizable material in the deoxygenation container, oxygen in the pipe flows into the deoxygenation container through the hole. Thereby, oxygen in the piping is removed, and generation of oxides can be suppressed during the brazing operation. Further, whether or not the deoxygenation operation has been performed can be easily determined from the appearance of the deoxygenation container (for example, heating marks), and the brazing operation can be performed smoothly.
[0016]
(4) In the refrigerant pipe according to (3), a heat transfer material that further transfers heat from outside the deoxygenation container to the oxidizable material is provided in the deoxygenation container. The piping and the connecting piping are covered with a heat insulating material that prevents heat propagation in the deoxygenation container on the outside.
[0017]
Therefore, by heating from the outside of the deoxygenation container with, for example, a burner, the oxidizable material can be burned through the heat transfer material. Thus, as described above, by burning the oxidizable material in the deoxygenation container, oxygen in the pipe flows into the deoxygenation container through the hole, and the oxygen in the pipe is removed, Oxide generation can be suppressed during the attaching operation. Moreover, it can be determined easily from the external appearance (for example, heating trace) of a deoxidation container whether the deoxygenation work was performed, and a brazing operation | work can be performed smoothly. On the other hand, since each pipe is covered with a heat insulating material, the shape change of each pipe due to heating during deoxidation can be suppressed, and brazing can be performed even in a place where a large pipe stress acts due to vibration. it can.
[0018]
(5) In a refrigerant pipe formed by brazing a connected pipe with an expanded portion of a connection pipe, one end of the refrigerant pipe is connected to the connection pipe and / or the connection pipe to introduce gas in the pipe to the outside And a valve provided in the introduction pipe for opening and closing the flow of gas in the introduction pipe, and detachably connected to the other end of the introduction pipe and oxygen in the pipe at the time of brazing between the connected pipe and the connection pipe A deoxygenation device having a deoxygenation container for suction and removal.
[0019]
Therefore, when performing a deoxygenation operation, the oxygen in the pipe can be removed by sucking into the deoxygenation container through the introduction pipe through the valve. Furthermore, if the valve is closed, the deoxygenation container can be replaced, and the deoxygenation operation can be performed any number of times. Moreover, internal oxygen can be removed without restricting the shape and diameter of the pipe for brazing.
[0020]
(6) In the refrigerant pipe according to (5), the deoxygenation container includes an oxidizable material and a heat transfer material that transmits heat from outside the deoxygenation container to the oxidizable material. And having.
[0021]
Therefore, by heating from the outside of the deoxygenation container with, for example, a burner, the oxidizable material can be burned through the heat transfer material. Thus, as described above, by burning the oxidizable material in the deoxygenation container, oxygen in the pipe flows into the deoxygenation container through the introduction pipe, and oxygen in the pipe is removed. . Thereby, the production | generation of an oxide can be suppressed at the time of brazing operation | work. Moreover, it can be determined easily from the external appearance (for example, heating trace) of a deoxidation container whether the deoxygenation work was performed, and a brazing operation | work can be performed smoothly.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the component similar to the conventional refrigerant | coolant piping mentioned above, and the description is abbreviate | omitted.
[0023]
Embodiment 1 FIG.
As shown in FIG. 1, the refrigerant pipe of the present embodiment is provided with a deoxygenation device for sucking and removing oxygen in the pipe at the time of brazing to the connected pipe 1 and the connecting pipe 2.
[0024]
As shown in FIG. 2, the deoxygenation device includes at least one deoxygenation container 8 containing the oxidizable material 10 outside the connected pipe 1 and the connecting pipe 2, and each pipe 1, 2 and the deoxygenating apparatus. A hole 12 communicating with the oxygen container 8 is provided. Further, in the deoxygenation container 8, a heat transfer material 11 for transferring heat from the outside of the deoxygenation container 8 to the oxidizable material 10 and the hole 12 is provided with a filter 9 provided in the vicinity of 12 for preventing the oxidizable material 10 from flowing into each pipe. In addition, the connected pipe 1 and the connecting pipe 2 are covered with a heat insulating material 13 that prevents heat propagation in the deoxygenation container 8 on the outside.
[0025]
Here, the hole 12 may be provided on the entire circumference of the pipes 1 and 2. In this case, the deoxidation container 8 may be provided so as to cover a part of the outer periphery of the pipes 1 and 2. The oxidizable material 10 may be steel wool, for example.
[0026]
That is, in this embodiment, the deoxygenation device is attached to the pipe in advance so that it is not necessary to remove it after the deoxygenation work.
[0027]
When performing the brazing operation, the expanded portion 3 of the connection pipe 2 is fitted to the connected pipe 1. The expanded pipe part 3 is closely attached to the connected pipe 1 with no gap so that outside air does not enter the inside of the pipe. Next, the periphery of the deoxygenation container 8 is heated with a burner or the like. The heat is transferred to the heat transfer material 11 via the deoxygenation vessel 8 and further transferred to the oxidizable material 10 via the heat transfer material 11. When the oxidizable material 10 is heated to a high temperature, oxygen around the inside of the expanded pipe portion 3 flows in through the hole 12 and is consumed by a chemical reaction (combustion). On the other hand, the heat insulating material 13 prevents reaction heat of the oxidizable material 10 from propagating to the connected pipe 1 and the connecting pipe 2.
[0028]
In a state where oxygen around the inside of the expanded pipe portion 3 is absorbed (burned) by the material 10 that can be sufficiently oxidized, the expanded pipe portion 3 is heated with a burner or the like, and the connected pipe 1 and the connected pipe 2 are brazed.
[0029]
As a result, by burning the oxidizable material 10 in the deoxygenation container 8, oxygen in the pipes 1 and 2 flows into the deoxygenation container 8 through the holes 12, and oxygen in the pipes 1 and 2 flows. It is removed and the generation of oxides can be suppressed during the brazing operation. Further, whether or not the deoxygenation operation has been performed can be easily determined from the appearance (for example, heating marks) of the deoxygenation container 8, and the brazing operation can be performed smoothly. Furthermore, no special tools / equipment other than the burner are required during the deoxidation work, and the work is simplified and the work cost is reduced. Moreover, since each piping 1 and 2 is coat | covered with the heat insulating material 13, the shape change of each piping 1 and 2 by the heating at the time of deoxygenation can be suppressed. For this reason, brazing joining can be performed even in a place where a large pipe stress acts due to vibration.
[0030]
In the present embodiment, the deoxygenating device is provided in both the connected pipe 1 and the connecting pipe 2. However, the present invention is not limited to this. You may provide in either one of the piping 2. FIG.
[0031]
Embodiment 2. FIG.
In the first embodiment, the deoxygenation device is attached to the pipe in advance so that it does not need to be removed after the deoxygenation work is performed. However, in the present embodiment, as shown in FIGS. The deoxidation container 18 of the deoxygenation device is detachably provided. In addition, the same code | symbol is attached | subjected to the structure same as the structure of the said Embodiment 1, and the description is abbreviate | omitted.
[0032]
As shown in FIG. 3, in the refrigerant pipe of the present embodiment, one end of the introduction pipe 14 for introducing oxygen in the pipe expansion portion 3 is connected to the connection pipe 2 and opens and closes the gas flow in the introduction pipe 14. A valve 16 is provided in the introduction pipe 14. Further, at the other end of the introduction pipe 14, a deoxygenation container 18 is provided that detachably attaches oxygen to the pipe when sucking the connection pipe 2. Further, in the deoxygenation container 18, an oxidizable material 10 is built in, and a heat transfer material 11 that transmits heat from the outside of the deoxygenation container 18 to the oxidizable material 10 is provided.
[0033]
When performing the brazing operation, the periphery of the deoxidation container 18 is heated with a burner or the like with the valve 16 opened. This heat is transferred to the heat transfer material 11 through the deoxygenation vessel 18 and further propagates to the oxidizable material 10. When the oxidizable material 10 reaches a high temperature, oxygen in the periphery of the expanded pipe portion 3 is absorbed and consumed by the oxidizable material 10 through the introduction pipe 14 by a chemical reaction (combustion). After sufficiently removing oxygen around the expanded pipe 3, the expanded pipe 3 is heated with a burner or the like, and the connected pipe 1 and the connected pipe 2 are brazed.
[0034]
Therefore, the oxygen around the joint can be removed simply by heating the deoxygenation container. Furthermore, if the valve 16 is closed, the deoxygenation container 18 can be replaced, and the deoxygenation operation can be performed any number of times. Moreover, internal oxygen can be removed without restricting the shape and diameter of the pipe for brazing.
[0035]
In addition, as in the first embodiment described above, a material that can be oxidized can be burned through the heat transfer material by heating from the outside of the deoxygenation container with, for example, a burner. As a result, oxygen in the pipe flows into the deoxygenation container through the introduction pipe, oxygen in the pipe is removed, and generation of oxide can be suppressed during the brazing operation. Moreover, it can be determined easily from the external appearance (for example, heating trace) of a deoxidation container whether the deoxygenation work was performed, and a brazing operation | work can be performed smoothly.
[0036]
In this embodiment, the introduction pipe 14 is connected to the connection pipe 2, but the present invention is not limited to this, and the introduction pipe 14 may be connected not only to the connection pipe 2 but also to the connected pipe 1. Further, it may be connected only to the connected pipe 1.
[0037]
【The invention's effect】
As mentioned above, according to the refrigerant | coolant piping which concerns on this invention, the apparatus which flows in inert gas into a piping like the past becomes unnecessary. Further, whether or not the work for suppressing the oxide before the brazing work has been performed can be easily determined from the appearance of the deoxygenation apparatus and the appearance (heating mark) of the deoxygenation container. Therefore, the work is simplified, and the connected pipe and the connecting pipe can be brazed while reliably suppressing the oxide.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a configuration of a refrigerant pipe provided with a deoxygenation apparatus according to the present invention.
FIG. 2 is a diagram showing a configuration of a deoxygenation apparatus shown in FIG.
FIG. 3 is a view showing another example of the configuration of the refrigerant pipe provided with the deoxygenation apparatus according to the present invention.
4 is a diagram showing a configuration of the deoxygenation device shown in FIG. 3. FIG.
FIG. 5 is a view showing a configuration of an inert gas replacement jig used in a conventional deoxidizing brazing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe to be connected, 2 Connection piping, 3 Expanded part, 4 Adhering tool, 5 Injection pipe, 6,16 Valve, 7 Cylinder, 8,18 Deoxygenation container, 9 Filter, 10 Oxidizable material, 11 Heat transfer material, 12 holes, 13 heat insulating material, 14 introduction pipe.

Claims (6)

In the refrigerant piping formed by brazing the expanded portion of the connecting piping to the connected piping,
A refrigerant pipe characterized in that a deoxidation device for sucking and removing oxygen in the pipe at the time of brazing is provided on the connected pipe. In the refrigerant piping formed by brazing the expanded portion of the connecting piping to the connected piping,
A refrigerant pipe characterized in that a deoxygenation device for sucking and removing oxygen in the pipe at the time of brazing is provided on each of the connected pipe and the connecting pipe. In the refrigerant piping according to claim 1 or 2,
The deoxygenation device includes at least one deoxygenation container containing a material capable of being oxidized outside the connected pipe or the connected pipe and the connecting pipe, and a hole communicating the pipe and the deoxygenating container. Is provided,
A refrigerant pipe characterized by removing oxygen in the refrigerant pipe by burning an oxidizable material in the deoxygenation container. In the refrigerant piping according to claim 3,
In the deoxygenation container, a heat transfer material is further provided to transmit heat from outside the deoxygenation container to the oxidizable material, and the connected pipe and the connection pipe are provided outside the deoxygenation container. Refrigerant piping, characterized by being coated with a heat insulating material that prevents the propagation of heat. In the refrigerant piping formed by brazing the expanded portion of the connecting piping to the connected piping,
One end of the pipe to be connected and / or the pipe to be connected and an introduction pipe for introducing the gas in the pipe to the outside,
A valve provided in the introduction pipe for opening and closing a gas flow in the introduction pipe;
A deoxidation container that is detachably connected to the other end of the introduction pipe and sucks and removes oxygen in the pipe when brazing the connected pipe and the connecting pipe;
A refrigerant pipe comprising a deoxygenation device having In the refrigerant piping according to claim 5,
The deoxidation container has therein an oxidizable material and a heat transfer material that transfers heat from outside the deoxygenation container to the oxidizable material.

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