JP2611869B2 - Tube and plate welding method - Google Patents

Description

The present invention relates to a method for welding a tube and a plate,
Particularly, the present invention relates to a method of welding a tube and a plate having excellent workability, which can weld the entire circumference of a metal tube having an oval cross section by one linear scan using a tungsten inert gas welding apparatus.

2. Description of the Related Art Conventionally, joining between a tube and a plate, for example, a tube of an automobile radiator and a tank plate has been performed by soldering. However, according to the joining method, even if soldering is neat and careful so as not to leak, when heated in the next step, the solder of the soldered portion will melt,
There was a drawback that it would be defective. In addition, the bonding strength by solder is weak, and when used for a long period of time, there is a disadvantage that the soldered portion is deteriorated due to the vibration of the automobile or the pressure in the radiator and water leaks easily.

In order to improve this, there is an example of a very special automobile radiator in which the tube and the tank plate are joined by welding.However, a welding device is installed along the shape of the open end of the tube, that is, an oval shape. Since the method involves welding while moving, the workability is poor, not only takes a long time for welding, but also has the drawback that work cannot be performed without skilled workability, and that the welding cost is high.

Japanese Patent Application Laid-Open No. 58-163582 discloses a TIG welding method. However, in the conventional example, a circular shape is formed along a welded portion, that is, along the edge of a joint portion between a pipe and a tube sheet, if the shape is circular. In addition, a method in which a torch is scanned and one edge is welded linearly in a narrow area, and a filler material is required. In the cited invention (FIG. 4), a filler wire is used as the filler material. In the prior art invention (FIG. 5), powdered filler metal is stored in a container, supplied to the welding portion from the guide nozzle, and melted by the heat of the gas from the torch. In this method, the torch is moved linearly along the center of the oval shape in the longitudinal direction to scan both edges of the oval hole at the same time, and the opening end is scanned in one scan. Welds the entire circumference without corners and forms an alloy layer between metals without using any filler material. The present invention is welded construction and operational effects are quite different.

Purpose The present invention has been made in order to eliminate the above-mentioned disadvantages of the prior art, and an object thereof is to weld a metal tube and a plate by using a tungsten inert gas welding device. It is to improve the strength of the joint, and by this, it is possible to prevent the influence of the joint even if heated in the next step and improve the durability of the radiator to completely prevent water leakage. is there. It is another object of the present invention to scan the entire circumference of a metal tube having an elliptical cross section linearly once along the substantially center of the open end in the longitudinal direction of the open end of the metal tube. An object of the present invention is to make it possible to perform welding without using an additive, thereby greatly facilitating the welding operation as compared with the conventional example and greatly improving the workability of welding.

Configuration In short, the present invention provides a metal tube having an elliptical cross section by linearly moving a torch portion of a tungsten inert gas welding device in a longitudinal direction of the opening end of the metal tube substantially along the center of the opening end. The open end of the tube is formed by the spread of the tungsten inert gas welding arc over the entire periphery of the open end and the edge of the hole of the metal plate in which a hole having substantially the same shape as the open end is formed. The present invention is characterized in that the edge of the plate is melted to form an alloy layer in which these two metals are melted, thereby welding without using a filler material.

Hereinafter, the present invention will be described based on embodiments shown in the drawings. 1 to 5, a radiator 1 manufactured by a welding method according to the present invention includes a tube 2, a tank plate 3, which is an example of a plate, an upper tank 4, and a lower tank 5. The tube 2 is a tube made of, for example, a copper plate having a thickness of 0.15 mm and having an oblong cross-sectional shape having a length of 13 mm in a longitudinal direction and a length of 2 mm in a transverse direction. A large number of tubes 2 are arranged in parallel. Have been. The two ends 2b and 2c of the plurality of tubes 2 have a thickness of, for example, 0.9 m.
holes 3 of the same shape as the cross-sectional shape of the tube 2
a is inserted into the holes of the tank plate 3 manufactured by aligning and drilling, soldered by a solder 4 as an example of a sealing material, and further subjected to tungsten inert gas welding.

Each of the tank plates 3 is configured as a part of the upper tank 4 and the lower tank 5, and the cooling water taken in from the upper hose connection port 4a is passed through the tube 2, and the heat of the cooling water is fin-transferred to be cooled. After
The lower hose connection port 5a is configured to return to an engine (not shown).

Next, the welding of the tube 2 and the tank plate 3 will be described in detail. Referring to FIGS. 1 to 3, the opening of the tube 2 is applied while applying a light voltage to the voltage 8a of the torch 8 of the tungsten inert gas welding apparatus. Scanning is performed linearly in the direction of arrow A along the substantial center of the opening end in the longitudinal direction of the end 2a. The arc of tungsten inert gas welding with high-temperature argon gas 9 radiated from the torch part 8 in the direction of arrow B is as follows:
The edge of the open end 2a of the tube 2 and the edge of the hole 3a of the tank plate 3 are melted to form an alloy layer 10 in which both metals are melted (see FIG. 5) and are welded firmly.

The present invention is configured as described above, and its operation will be described below. Referring to FIGS. 1 to 3 and 5, a torch portion 8 of the tungsten inert gas welding device is opposed to the open end 2a of the tube 2 joined to the tank plate 3 by solder 7, and a high voltage is applied to the electrode 8a. While scanning, the tube 2 is linearly scanned in the direction of the arrow A in the longitudinal direction of the open end 2a substantially along the center of the open end (see FIG. 3). The arc of the tungsten inert gas welding with the high-temperature argon gas 9 radiated from the torch portion 8 in the direction of arrow B is radiated while gradually expanding, and simultaneously heats the entire circumference of the opening end 2a of the tube 2 to open the tube 2 The end 2a and the edge of the tank plate 3 are melted to form an alloy layer 10 in which both metals are melted.
The whole circumference of is strongly welded. Also, at this time, since welding is performed by melting the material of the tube 2 and the tank plate 3, it is not necessary to add a filler such as a welding rod.

As described above, a large number of tubes 2 arranged in an aligned manner
The tube 2 and the tank plate 3 can be easily welded only by scanning the approximate center of the opening end 2a linearly in the direction of arrow A along the longitudinal direction. In the example shown in FIG. 3, the radiator 1 can be manufactured by welding the tube 2 and the tank plate 3 very efficiently only by five linear scans.

Effect As described above, the present invention welds a metal tube and a plate using a tungsten inert gas welding device, so that the strength of the joint can be improved, and as a result, the metal is heated in the next step. Even so, there is an effect that it is possible to prevent the influence on the joint portion and to improve the durability performance of the radiator to completely prevent water leakage. In addition, no filler material is used by scanning the entire circumference of the metal tube having an oval cross section linearly once in the longitudinal direction of the opening end of the metal tube along the substantially center of the opening end. Welding can be completed without any problems.
This has the effect of greatly improving the workability of welding.

[Brief description of the drawings]

1 is a perspective view showing a welding state between a tube 2 and a tank plate 3, FIG. 2 is a longitudinal sectional view of an essential part, and FIG. 3 is a plan view of a welded portion. FIG. 4 is a partially omitted front view of the radiator, and FIG. 5 is an enlarged vertical sectional view of a main part of the welded portion. 2 is a tube, 2a is an open end, 3 is a tank plate as an example of a plate, 3a is a hole, and 8 is a torch part of a tungsten inert gas welding device.

Continuation of the front page (72) Inventor Akinori Furusho 3-1-1 Hinodai, Hino-shi, Tokyo Inside Hino Automotive Industry Co., Ltd. (56) References JP-A-58-163582 (JP, A)

Claims (1)

(57) [Claims] 1. An open end of a metal tube having an elliptical cross section by linearly moving a torch portion of a tungsten inert gas welding device along a substantially center of the open end in a longitudinal direction of the open end of the metal tube. And the edge of the hole of the metal plate in which a hole having substantially the same shape as the opening end is formed, and the arc of the tungsten inert gas welding is spread over the entire circumference of the opening end to form the opening end of the tube and the plate. A method for welding a tube and a plate, comprising welding an edge portion to form an alloy layer in which these two metals are melted, without using a filler material.