JPH08207138A - Method of welding piping cylinder - Google Patents

Abstract

PURPOSE: To enable a hose to be riveted positively to a fastening part by preventing softening due to the heat-influences of brazing or welding. CONSTITUTION: This welding method is for a piping cylinder 1 having a heat welding part 2 to be welded with a welded member 4 and a fastening part 3 to be riveted with a hose in the vicinity of the heat welding part 2, and after the cooling water jacket 11 is mounted on the outer periphery of the fastening part 3, the welded member 4 is welded to the heat welding part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for welding a cylindrical body for piping. More specifically, it is a cylindrical body for piping to which hoses used for refrigerant piping of an air conditioner system in automobiles and motorcycles are connected, for attaching a mounting flange, a charge valve, etc. to the cylindrical body. The present invention relates to a method for welding a pipe cylinder.

[0002]

2. Description of the Related Art As a conventional pipe cylinder, there is a hose fitting 51 as shown in FIG. A mounting flange 52 for fixing to a member such as a pump is attached to one end of the hose fitting 51 by welding such as brazing or welding. When using the hose fitting 51, the hose H is caulked and fixed to the other end by the outer cylinder 53.

When the hose H is caulked and fixed to the hose crimp portion 54, especially when the material of the hose fitting 51 is aluminum alloy, the hose crimp portion 54 is softened by the heat effect of brazing or welding. Therefore, the hose caulking portion 54 is greatly deformed by reducing the diameter. Therefore, sufficient compression force cannot be applied to the hose H, and the hose tightening portion 54
As a result, the refrigerant and the like tend to leak, and the durability could not be ensured. As a measure against such a problem, conventionally, an alloy that can be hardened by heat treatment is adopted as an aluminum alloy, and after brazing or welding, heat treatment for quenching and tempering is performed, and a method for recovering the strength capable of withstanding a caulking force, For example, a method of inserting a sleeve made of stainless steel into the inner diameter of the hose fitting 51 to reinforce it is used.

However, the method of recovering the strength by reheat treatment has a problem in that the cost for reheat treatment is high. In addition, the method of reinforcing with a sleeve has the problems that the number of parts increases and the cost for inserting the sleeve increases.

In view of the above circumstances, the present invention provides a method of welding a cylindrical body for piping, which can prevent softening due to the heat effect of brazing or welding and can reliably crimp the hose to the crimped portion. The purpose is to

[0006]

A method of welding a cylindrical body for piping according to the present invention has a heat-welded portion to which a member to be welded is welded and a caulking portion to which a hose is caulked near the heat-welded portion. A method of welding a cylindrical body for piping is characterized in that a water cooling jacket is attached to the outer periphery of the caulking portion, and then a member to be welded is welded to the heat welding portion.

The gap between the crimped portion and the water cooling jacket is preferably about 0.02 to 5 mm.

The amount of cooling water in the water cooling jacket is 5 cc /
It is preferably at least min.

The welding can be performed by brazing or welding.

An aluminum alloy can be used as the pipe cylinder.

[0011]

According to the method for welding a pipe cylinder of the present invention, a water cooling jacket is attached to the outer periphery of the caulking portion, and then a member to be welded such as a flange or a charge valve is welded to the heat welding portion. The temperature rise of the crimped part due to the heat effect is suppressed. As a result, it is possible to prevent softening of the crimped portion, and it is possible to securely crimp the hose to the crimped portion without reheat treatment or reinforcement with a sleeve.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A welding method for a pipe cylinder according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an explanatory view showing one embodiment of a method for welding a pipe cylindrical body of the present invention, FIG. 2 is a perspective view showing another embodiment of the water cooling jacket in FIG. 1, and FIG. 3 is welding in FIG. Explanatory drawing showing the amount of deformation of the crimping portion when the hose is crimped to the metal fitting obtained by the method, FIG. 4 is an explanatory view showing another embodiment of the welding method of the pipe cylinder of the present invention, 5 is an explanatory view showing the amount of deformation of the caulking portion when the hose is caulked to the metal fitting, which is obtained by the welding method in FIG. 4, and FIG. 6 is another embodiment of the welding method for the pipe cylinder of the present invention. It is explanatory drawing which shows an example.

As shown in FIG. 1, a pipe cylinder 1 according to the present invention is composed of a caulking portion 3 in which a hose is caulked near a heat welding portion 2.

The pipe cylinder 1 is used for hose fittings to which refrigerant hoses used in vehicles such as automobiles are connected, hose fittings to which hydraulic hoses in various hydraulic systems are connected, and other general hydraulic equipment. Such as hydraulic hose fittings. A welded member 4 such as a flange or a union joint for fixing to a member such as a pump is welded to one end of the pipe cylinder 1. In the present invention, the one end is not limited to the one to which the welded member 4 such as the flange is welded, and the outer peripheral intermediate portion 5 of the pipe cylinder 1 is charged with the refrigerant as shown in FIG. For example, a charge valve 34 for welding may be welded, or a sight glass, a bracket, or a port or a branch pipe for branching the flow may be welded.

As the material of the pipe cylinder 1, aluminum alloy, copper alloy, mild steel, etc. can be used.
As the welding method, brazing, welding, soldering, etc. can be adopted.

The caulking portion 3 is provided with three circumferential grooves 6 for crimping the outer circumference of an outer cylinder (not shown) to be fitted on the hose and for securely crimping the hose. The circumferential groove 6 can be formed by rolling or cutting.
In addition, 7 is an outer peripheral groove for fixing the outer cylinder. Further, in the present invention, the number of the circumferential grooves 6 is not limited to three, and can be appropriately selected from 0 to about 10 depending on the application, required performance, caulking method, hose specifications and the like. . The groove may be replaced by a ring-shaped convex shape.

The method for welding a pipe cylinder of the present invention is characterized in that a water cooling jacket is attached to the outer periphery of the caulking portion, and then a member to be welded is welded to the heat welding portion.

As shown in FIG. 1, the water cooling jacket 11
Is composed of a circulating water channel 13 formed in a cylindrical portion 12 having a bottomed cylindrical shape, and inlet / outlet ports 14 and 15 for allowing cold water to flow in and out of the circulating water channel 13. . The water cooling condition of the water cooling jacket can be appropriately selected depending on the hose tightening force, welding conditions, effective size of the crimp portion, the gap between the crimp portion and the water cooling jacket, the material of the metal fitting, the shape of the metal fitting, and the like. In the case of aluminum alloy metal fittings having a relatively small size as in the embodiment, a water amount of about 5 cc / min is sufficient. However, if the shape is large and the heat capacity is large, or if the material has a higher melting point than aluminum alloys such as iron and copper alloys, the temperature becomes higher during welding, and when brazing, the melting point is higher than that of aluminum alloys. Since a brazing filler metal having a temperature of 100 ° C. is used, the temperature required for welding is high, and the amount of heat to be removed is inevitably large. Therefore, the amount of cooling water is required to be several 100 cc / min or more.

However, even if the amount of cooling water is too large, it does not have a negative effect. Therefore, in actual work, even if a small amount is sufficient as in the above example, it is better to flow a larger amount without regard to it. Desirable for management and stability. In addition, the gap between the crimped portion and the water cooling jacket is preferably about 0.02 to 5 mm so that the water cooling jacket can be easily attached and detached and the cooling effect is enhanced.
In the welding method of the present invention, water cooling or air cooling may be performed after the completion of welding. Further, the water cooling jacket in the present invention is not limited to the bottomed cylindrical shape, and may be a penetrating cylindrical shape or the like.

Next, another embodiment of the water cooling jacket in the present invention will be described.

As shown in FIG. 2, a water cooling jacket 21
Is composed of half-moon-shaped members 22a and 22b which are open / closed by a hinge or the like. Each half-moon shaped member 2
Circulation channels (not shown) are formed inside 2a and 22b, and a circulation tube 2 is provided in each circulation channel.
3 are connected. As a result, the cold water is supplied to the inlet 24
From the outlet 25 through each circulation water channel and the circulation tube 23, and cools the caulking portion 3 during the circulation of the cold water.

Next, the method for welding the pipe cylindrical body of the present invention will be described based on examples, but the present invention is not limited to these examples.

Example 1 The pipe cylinder used in the test is a hose fitting having a caulking portion having three circumferential grooves formed at one end as shown in FIG. This hose fitting is made of aluminum alloy (606
3-T83), and the crimped portion has an average diameter P of 1
The length M from the heat-welded portion to the crimped portion is 80 mm.

In carrying out the welding method of the present invention using the hose fitting, first, the hose fitting is placed on the flange, and then a water cooling jacket is provided at the outer peripheral position of the caulking portion so that the gap becomes 0.05 mm. Put on. Then, the heat-welded portion of the hose fitting and the flange were brazed while the amount of cooling water was set to approximately 150 cc / min. After brazing was completed, it was placed in a water tank and cooled.

Next, a hose crimping test for evaluating the crimping deformation amount of the hose fitting obtained in Example 1 will be described.

The test method is as follows. A high-lamit hose (commercial name) with an outer cylinder inserted is fitted into the caulking portion, and then the outer cylinder is pressurized with a predetermined pressure to crimp the hose to the caulking portion. Then, it is a method of measuring the amount of deformation of the pipe cylinder in the swaged portion. The measurement result is shown in FIG. The measurement positions of the amount of deformation are positions A, B, C, and D shown in FIG. 1, and the amount of deformation in the radial direction is the average value at four locations on the circumference of each of the n samples. As shown in FIG.
The hose fitting (Example 1) obtained by the welding method according to the present invention is equipped with a pipe whose flange is not brazed, that is, a hose fitting which is not affected by heat at all (Comparative Example 1) and the water cooling jacket according to the present invention. Compared with a hose fitting (Comparative Example 2) in which the flange was brazed without
The deformation amount of Comparative Example 2 not using the water cooling jacket was large overall, and at the C position, the standard upper limit value L was exceeded, but the change amount was almost the same as that of Comparative Example 1 in which brazing was not performed. Despite the fact that the caulking part is close to the heat-welded part, it was found that the caustic part was hardly affected by the heat of brazing and was within the standard value.

Example 2 As shown in FIG. 4, the pipe cylinder used in the test is a hose fitting to which a charge valve 34 is brazed to an intermediate portion 35 thereof. A hose crimping test was conducted in the same manner as in Example 1 except that the effective length M from the heat-welded portion 32 to the crimped portion 33 was 70 mm, the average diameter P, the welding conditions and the test method were the same as in Example 1. As shown in FIG. 4 as a result of this measurement, the hose fitting (Example 2) obtained by the welding method according to the present invention is a hose fitting in which the charge valve 34 is not brazed (Comparative Example 3, Comparative Example 1). The same as Example 1) and the hose fitting in which the charge valve 34 is brazed without the water cooling jacket according to the present invention (Comparative Example 4), the deformation amount of Comparative Example 4 not using the water cooling jacket is C position. Although the standard value L was exceeded, the deformation amount was almost the same as in Comparative Example 3 in which brazing was not performed, and it was found that the deformation value was sufficiently within the standard value as in Example 1.

The hose fittings used in Examples 3 and 4 had an average diameter of the crimped portion of 12.
The same as Example 1 except that the length is 10 mm. Using this hose fitting, a water cooling jacket was attached to the crimped portion, the flange was brazed, and after brazing was completed, the hose fitting (Example 3) was obtained by cooling in a water tank. Instead of water cooling, a hose fitting (Example 4) cooled by a fan after brazing was completed was obtained.

Then, a hose crimping test was conducted in the same manner as in Example 1. The result is shown in FIG. As shown in FIG. 6, the deformation amount of the air-cooled Example 4 is slightly larger than the deformation amount of the water-cooled Example 3, but the basic upper limit value L is sufficiently large.
I found it inside.

[0031]

As described above, according to the method for welding a pipe cylindrical body of the present invention, when a flange or the like is welded by brazing or welding, the hose formed near the heat-welded portion is caulked. Since a water cooling jacket is attached to the portion for cooling, it is possible to prevent softening of the crimped portion due to thermal influence. As a result, the amount of deformation of the caulking portion when caulking the hose is small, and the strength before welding can be maintained. Further, since the conventional reheat treatment and the sleeve are not required, the cost and the production cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a welding method for a pipe cylinder according to the present invention.

FIG. 2 is a perspective view showing another embodiment of the water cooling jacket in FIG.

FIG. 3 is an explanatory diagram showing a deformation amount obtained by the welding method in FIG.

FIG. 4 is an explanatory view showing another embodiment of the welding method for the pipe cylinder of the present invention.

5 is an explanatory diagram showing a deformation amount obtained by the welding method in FIG.

FIG. 6 is an explanatory view showing still another embodiment of the welding method for the pipe cylinder of the present invention.

FIG. 7 is an explanatory view showing an example of a conventional hose fitting.

[Explanation of symbols]

 1 Pipe Cylindrical Body 2 Thermal Welding Part 3 Crimping Part 4 Welded Member 11, 21 Water Cooling Jacket

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Claims (6)

[Claims] 1. A method for welding a cylindrical body for piping, comprising: a heat-welded portion to which a member to be welded is welded; and a caulking portion to which a hose is caulked in the vicinity of the heat-welded portion. A method for welding a cylindrical body for piping, comprising: mounting a water-cooling jacket on the outer periphery and then welding a member to be welded to the heat-welded portion. 2. The welding method according to claim 1, wherein the gap between the crimped portion and the water cooling jacket is approximately 0.02 to 5 mm. 3. The cooling water amount of the water cooling jacket is 5 cc
/ Min or more, The welding method according to claim 1 or 2. 4. The welding method according to claim 1, 2 or 3, wherein the welding is brazing. 5. The welding method according to claim 1, 2 or 3, wherein the welding is welding. 6. The welding method according to claim 1, wherein the pipe cylinder is made of an aluminum alloy.