JPS5844976A - Connecting method for aluminum pipes - Google Patents

Abstract

PURPOSE:To produce aluminum pipes continuously by one time of a preparatory plan in the starting stage of work by swaging the connecting end parts of base materials for aluminum pipes substantially down to the prescribed finish size of the aluminum pipes and subjecting said parts to flash butt welding. CONSTITUTION:The respectively opposed connecting end parts 2 of the coils of base materials 1 for aluminum pipes are swaged to a taper shape by rolling whereby the joining end faces 3 of the parts 2 are worked substantially to the same size (d) as the finish size of aluminum pipes. The parts 2, 2 are mated at the faces 3 and welding electric power is applied between the parts 2 and 2 via electrodes 5, 5 from an electric power source 4 for welding, whereby said parts are subjected to flash butt welding. After the burrs 6 formed by the welding are ground away to smooth the parts 2, 2, the parts are finished with dies, whereby an aluminum pipe of a prescribed size is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing lightweight AC8RC steel core aluminum stranded wire, and a method for connecting an aluminum pipe to 45F.

As for connection methods for aluminum pipes, there are many connection methods used depending on the purpose (as disclosed in 1 literature). However, Connecting aluminum pipes requires expensive equipment and strict dimensional accuracy between the connecting ends of the aluminum pipes.In addition, the connection processing using conventional methods Since the connection work is performed at the final processing stage of the AC3R, the connection work must always be performed accurately, which is a factor that deteriorates workability.Furthermore, with this method, it is difficult to manufacture AC3R of the required length. Each coil of a very large number of aluminum pipe base materials is subjected to one-drawing process, passed through multiple dies, and wired to a continuous wire drawing machine.
Preparation work such as forming an aluminum pipe of a predetermined size must be repeated for each coil, which significantly deteriorates work efficiency.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks and to develop an aluminum pipe so that when manufacturing an aluminum pipe of a predetermined size from an aluminum pipe base material, only one set-up is required at the start of work. Provides a way to connect, it K
An object of the present invention is to disclose a method for connecting aluminum ξ-beams that can greatly improve work efficiency.

The method of connecting aluminum pipes according to the present invention is conventional.

It is necessary to connect each coil of the aluminum pipe base material in advance before processing the aluminum pipe base material into an aluminum pipe of the specified dimensions because the wall thickness of the aluminum pipe base material is thin compared to its outer diameter. When performing flash butt welding, even if pressure is applied between the joints and voltage is applied, misalignment occurs between the centers of the base metals to be connected, and the tensile strength is insufficient for wire drawing. This idea was developed based on the fact that it was not carried out due to the inability to maintain the

The connection method according to the present invention involves swaging each opposing connection end of an aluminum pipe base material into a tapered shape by rolling to a predetermined finish size of the aluminum pipe, and cleaning and brushing the connection ends to flush them. The gist is to connect by butt welding. This allows the aluminum pipes to be connected without centering the base materials at the base material stage, and also prevents the plastic deformation caused by the multiple dies used to process the aluminum pipes into a predetermined size at the connection end. It is possible to apply tensile strength between the connecting ends that is sufficient to withstand the area of becomes.

Next, a method for connecting aluminum and R-beams according to an embodiment of the present invention will be further explained with reference to the drawings.

Molded using an extruder. As shown in FIG. 1, an aluminum Eve base material 1 has a hollow circular cross-sectional shape.

As shown in FIG. 2, the opposing connection ends 2 of the coils of each aluminum pipe base material 1 to be connected are connected.

Swaged into a tapered shape by roll rolling.

At least the joining end surface 6 of each connection end 2 is AC8R.
Each is processed to have a dimension d that is substantially the same as the finished dimension of the aluminum pipe for. After the swaged connection ends 2 are cleaned and brushed for the next process of welding, the joint end surfaces 6 of the opposing connection ends 2 are brought into contact with each other, as shown in FIG. A flash butt welding machine equipped with electrodes 5 from a welding power source 4 on each connection end 2 is used to weld the two together.

At this time, conditions such as voltage, pressure, and welding stroke for flash butt welding are not particularly limited, but should be changed appropriately depending on the material, size, and shape of the workpiece, and preferably, Pieces should be welded as described above and subjected to a tensile test, and a combination of conditions that provides high tensile strength should be selected. As shown in Fig. 4, a burr 6 generally occurs between the connection ends 2 that are connected by welding, so such a burr 6 is removed by means such as grinding and flashing is applied. , as shown in FIG. 5, so that the surface is smooth and continuous.

The aluminum pipe base material 1 connected in this way is passed through a die so that it has the finished dimensions of the aluminum pipe to be manufactured, but the plastic deformation process by the die is performed between the joint ends 2 of the aluminum pipe base material 1. (excluding the overall unprocessed partial pressure, and the arrangement of the die, the plastic deformation resistance force generated when the aluminum quipe base material 1 passes through the die, the fracture of the part between the connecting ends 2) By appropriately selecting the load so that it is below the load, aluminum pipe 7 (Fig. 6) having a predetermined finished dimension can be manufactured continuously without the risk of breakage between the joined ends due to the pulling resistance force due to plastic deformation of the die. can.

In addition, in order to equalize or substantially eliminate the internal stress remaining in the aluminum pipe 7 after plastic deformation processing using a die, and/or to compensate for the size and shape of the aluminum pipe 70,
This continuous aluminum pipe is subjected to wire drawing processing using a wire drawing machine, but even in this case, since the connecting end 2 has already been formed into a predetermined finished size by roll rolling, there is no stress. Therefore, the wire drawing process can be performed continuously.

In addition, the pars on the inside of the pipe that may occur when connecting the above-mentioned connection ends by flash butt welding can be sufficiently removed when the copper core is inserted into the aluminum pipe. Even if it is left inside the pipe, the presence of particles can be completely ignored due to the close contact with the copper core.

In the above explanation, only aluminum pipes for %AC8R were explained, but the method can also be applied to copper pipes, iron pipes, etc.

From an economic point of view, pipe members with high plastic deformation resistance are preferably avoided in view of the tensile loads between the connecting ends. Furthermore, although it is best for the dimension d of the connection end to be swaged by roll rolling to be the same as the finished dimension of the pipe for the reasons mentioned above, the resistance to plastic deformation caused by the die or wire drawing machine The swage machining dimension d of the connection end is determined according to the difference between the
It is also possible to finish the pipe with dimensions that suitably approximate the finished dimensions of the aluminum pipe.

On the other hand, in extreme cases, the inside of the pipe between the connection ends that can occur due to flashmet welding can become partially solid, and this solid part and other parts The difference in plastic deformation resistance between the wire and the original hollow part becomes large, and during high-speed wire drawing, a sharp change in plastic deformation resistance occurs at the boundary point between the solid parts.

In order to avoid the possibility of wire breakage, it is preferable that the amount of plastic deformation in the portion between the connecting ends be sufficiently small so as not to create a substantial solidity due to a flash.

As described above, according to the present invention, plastic deformation and wire drawing can be performed after each coil is connected at the pipe base material stage.

By performing one set-up at the start of work, pipes with a predetermined finished size can be manufactured continuously.

This greatly improves work efficiency and has an extremely large economic effect.

[Brief explanation of the drawing]

1 to 6 are diagrams showing step-by-step a method for connecting pipes according to the present invention. 1-m-aluminum pipe base material 2-m-connection end 6-m-joint end surface 4-m-welding power source 5-m-electrode 6-1-burr 7-1-aluminum pipe

Claims (1)

[Claims] Each opposing connection end of each coil of the aluminum pipe base material is swaged to dimensions that are practically the same as the finished dimensions of the specified aluminum pipe, and a flash butt is formed between each of the swaged opposing connection ends. By welding and connecting each coil, aluminum pipes with predetermined finished dimensions can be manufactured continuously from the aluminum pipe base material.
How to connect ξ Eve.