JPS60106678A - Press welding method of copper alloy by resistance heating - Google Patents

Abstract

PURPOSE:To securely press-weld without the use of any welding material by using a resistance welding machine as a heating and pressurizing means and pressing and crushing the joint part under resistance heating by means of upper and lower electrodes attached with heating plates of electric resistance in the parts to be brought into contact with the joint part. CONSTITUTION:Copper alloy plates 1, 2 are supperposed at the respective top ends and are press-welded by electrodes 6, 7 attached with heating plates 4, 5. Current of 8-10KA is then conducted to the electrodes 6, 7 and the electrodes are pressurized from above and below under about 650kg to join the plates 1, 2.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a method for joining and sealing copper alloys by pressure welding using resistance heating, and is characterized in that it does not require a brazing filler metal or 7 lux. Regarding pressure welding method.

[Background of the invention]

Most conventional joining of copper alloys involves brazing using a burner, and most pipes are sealed by crushing them with pliers, etc., and then using brazing to eliminate the gap between the crushed parts. However, it had the following drawbacks.

(1) Both welding and brazing are done by hand.

e) This work also requires skill.

6) Sealing requires a lot of man-hours.

(4) Work speed is slow and automation is difficult.

[Purpose of the invention]

The object of the present invention is to produce brazing filler metal by only pressure welding by resistance heating.
The object of the present invention is to provide a method for easily bonding and sealing copper alloys using flux.

[Summary of the invention]

The feature of the present invention is that a resistance welding machine is used as a heating means for 0 pressure, and resistance heating is performed by an upper F electrode with a high/0 heat generating plate of high air resistance attached to the part that contacts the joint. This involves crushing one piece, and creating a strong pressure weld without touching the welding material at all.

[Embodiments of the invention]

An embodiment of the present invention will now be described with reference to the drawings.

FIG. 1 shows an example in which copper plates are overlapped and pressed together. Copper plates 1 and 2 are stacked at each end and are resistance pressure welded by electrodes 6.degree. 7 with heating plates 4 and 5 attached. The principle of this bonding is that both the heat generated by the heating plate due to electricity and the contact resistance heat at the stacked copper plate soften and expand the copper plate, creating a new surface and causing a diffusion phenomenon at the contact interface, resulting in complete adhesion. It is something. By increasing the flow rate, the deformation resistance of the copper plates at the joint is reduced, the plate collapses in the thickness direction, the area of the overlapping surface increases, and the new surface becomes larger, increasing the joint strength.

Fig. 2 shows a row for sealing the ends of copper pipes; a shows pipe 1 sandwiched between heat generating plates 5 and 4, and b shows pressure welding by energizing and pressurizing. FIG. As before, the pressed parts are crushed by heat and pressure, and a diffusion phenomenon occurs at the interface, resulting in complete contact. In this case, the advantage is that there is no sharp point unlike cold sealing.

In the case of a copper plate, an example of pressure welding of a steel plate with a width of 141 mm and a thickness of 1.5 m requires a current of 20 KA and a current application time of 39 Hz.

Under one condition of applying force of 1ooo4, the thickness of the overlapped portion becomes approximately %, the overlap area increases by approximately 50%, and the bonding strength is approximately 280 kg in terms of tensile breaking load. Also 52
When sealing the end of a copper pipe of size 18 to 10, the current conditions are 8 to 1 QKA and a wake-up time of 30 liters.

The pressing force is 650 kg, but in each case it is the heating plate that makes important movements. By using a heat generating plate having higher electrical resistance than copper, heat can be efficiently and precisely conducted to the pressure welding part. Without this, the heat would not be concentrated and it would be impossible to pressure-weld copper-plated metals by resistance heating.The energizing conditions can be adjusted by changing the material and thickness of the heating plate depending on the capacity of the resistance welding machine and the form of the copper alloy. can do.

According to this embodiment, the copper alloy can be joined and sealed in a short time, and if the operation is automated, mass production is possible without requiring human labor.

Furthermore, by using heat-resistant tool steel, high-speed steel, or the like for the heating plate, wear of the resistance heating electrode, which is the most problematic in mass production, can be greatly reduced.

〔Effect of the invention〕

According to the present invention, conventional copper alloy joining is mostly done manually,
Although it requires time and skill on the part of the operator, if the pressure welding conditions are appropriately established, stable pressure welding can always be mechanically performed at high speed and easily. The quality and economic effects are also very large.

[Brief explanation of drawings]

Fig. 1 is an embodiment of the present invention, which is a sectional view of the main part in a state where a copper plate is pressure-welded by resistance heating, and Fig. 2 is an embodiment of the present invention, which is a main part in a state where a copper pipe is sealed. In the cross-sectional views, a shows a state in which the end of the copper pipe is sandwiched between electrodes, and b shows a state in which the ends are pressed together. 1.2...Copper plate, 6...Copper pipe, 4.5...Heating plate, 6.7...Electrode. Dormitory 1 Diagram 2 Diagram a, -1

Claims (1)

[Claims] 1. Using a resistance welding machine, two pieces of sheet steel alloy are overlapped at each end, and the parts are energized by upper and lower electrodes with heating plates with high drowsiness resistance placed in the contact parts. A pressure welding method for copper alloys that uses resistance heating to join by pressing and crushing. 2. The copper alloy is in the shape of a pipe, and this pipe is sealed.
To achieve this, a method of pressure welding copper alloys using resistance heating, in which the upper and lower electrodes are fitted with heat generating plates with a high resistance to drowsiness at their contact points, and are crushed while being heated with resistance.