JPH0824953B2 - High-density packed capillary manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a high-density filling thin tube applicable to the production of flux-filling welding wire, heat-resistant alloy welding wire, superconducting ceramics-filled thin tube and the like. .

[Prior Art] For example, in submerged arc welding, a flux is put on a welding portion, a welding wire is inserted into the flux, and welding is performed by an arc.

Therefore, the welding operation cannot be performed in a welding position where flux cannot be accumulated, and it is not suitable for welding the entire circumference of a pipe.

Therefore, a welding rod around which a flux layer is formed and a welding wire in which flux is wrapped in a welding metal plate have come to be used.

[Problems to be Solved by the Invention] However, in the case where the flux layer is formed around the welding rod, the flux layer is easily peeled off, which makes it difficult to handle,
It was limited to short ones.

In addition, since the flux is wrapped with a weld metal plate, the flux is wound with a weld metal plate and then lengthened by a drawing process. Light and shade are likely to occur, and in some cases they may be interrupted.

[Means for Solving the Problems] The present invention is intended to solve the above-mentioned problems and to manufacture long capillaries filled with a packing material at a high density. A filling material consisting of a cylindrically-shaped sintered body having a hole penetrating in the axial direction or at least one easily ductile metal wire inside, and The present invention relates to a method for producing a high-density packed thin tube, which comprises inserting the metal tube into a metal tube, stretching the metal tube together with the filler, and then drawing the tube.

[Operation] When the metal tube containing the filler is stretched and processed, the metal tube is elongated and thinned, and the filler inside is made to squeeze the holes or stretch the metal wire so as to be integrated with the metal tube. Stretches uniformly and thinly.

If the outer shape is modified by wire drawing, a long, densely packed thin tube can be obtained.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a metal tube 2 into which a filler 1 before being stretched is inserted in the manufacturing method of the present invention, the metal tube 2 being relatively ductile of stainless steel, Inconel, copper or the like. A metal or alloy of high quality is used, and the pipe diameter and length depend on the purpose of use, but for welding, an outer diameter of about 10 ^mmφ , an inner diameter of about 8 ^mmφ , and a length of about 200 mm may be used.

The filler 1 may have a constituent material selected according to the purpose of use. For general welding, a flux is used, and for welding a heat-resistant alloy or a hard alloy, a powder of chromium, nickel, cobalt, tungsten, etc. in the flux. Is added so that it has a predetermined ratio with the outer metal when melted. For superconductivity, superconducting ceramics such as niobium, titanium, zirconium, tin, vanadium and gallium are used.

Before the filler 1 is inserted into the metal tube 2, one or more holes 3 penetrating in the axial direction are provided. As a method of providing the hole 3, the metal wire having the same diameter as the hole 3 may be put in and then the metal wire may be pulled out before or after the heat treatment. You may set it up.
Instead of providing the hole 3, a ductile metal wire may be inserted in the axial direction. Here, the diameter of the hole 3 or the metal wire,
The number and arrangement may be appropriately selected according to the stretching ratio, and when the stretching ratio is large, the diameter may be increased and / or the number may be increased.

The heat treatment conditions for the filling 1 differ depending on the constituent materials, but may be such that a bisque-fired sintered body is obtained.

As described above, the filler 1 shaped like a lotus root may be machined to improve the outer diameter accuracy before being inserted into the metal tube 2.

As a means for inserting the filler 1 into the metal tube 2 and then stretching it, for example, a method generally called swaging can be mentioned. That is, forging is performed by tapping the outer periphery of the metal tube 2 with the right and left molds to reduce the diameter and stretch. At this time, as the metal tube 2 is stretched, the filler 1 therein is also deformed and stretched so that the holes 3 are crushed. This is also the case when a ductile metal wire is used instead of the hole 3.
In this way, the hole 3 is almost completely crushed and the metal wire is thinned, and the metal tube 2 is stretched in a state in which it is thin and the packing is densely packed until the outer diameter becomes about 1 mm to 0.5 mm.

Since the outer diameter may not always be uniform when stretched, the shape and surface state are made uniform by lightly drawing with a die.

The manufacturing method of the present invention is not limited to the above-mentioned embodiments, and various changes may be made without departing from the gist of the present invention such that annealing may be performed as necessary. Of course.

[Effects of the Invention] As described above, according to the method for producing a high-density packed thin tube of the present invention, various excellent effects as described below are exhibited.

(I) Since the cylindrical filler is inserted into a metal tube and stretched, a long and flexible metallic thin wire in which the filler is densely and uniformly filled can be obtained. .

(II) If the filler is a flux material, a long flux-cored welding wire can be obtained, the time and effort required for exchanging the welding rod are significantly reduced, and automatic welding is also possible. Further, since the flux can be uniformly filled, the welding conditions are stable and welding defects can be prevented.

(III) Welding materials such as super heat resistant alloys and cemented carbides can be easily reduced in diameter and length by adding powders of hard metals such as chromium and tungsten to the filler. Regardless of the method, the time and effort for exchanging the welding rod can be reduced, and defective welding can be prevented.

(IV) When the superconducting ceramic is used for the filling material, a superconducting ceramic thin wire whose outside is coated with a metal can be obtained, which facilitates coil winding and the like, and enables the superconducting ceramic to be used in various fields. Further, the metal coating layer on the outer side can secure the electric conductivity outside the temperature range where the superconducting phenomenon occurs and prevent burnout.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a metal tube in which a filler used for carrying out the manufacturing method of the present invention is inserted, and FIG. 2 is II-II of FIG.
It is a direction arrow view. Reference numeral 1 is a filler, 2 is a metal tube, and 3 is a hole.

Claims (1)

[Claims] 1. A bisque-like sintered body formed into a cylindrical shape having at least one hole penetrating in the axial direction or at least one ductile metal wire inside, the filler made of powder material, A method for producing a high-density packed thin tube, which comprises inserting a packed material into a metal tube, stretching the metal tube together with the packing material, and then drawing.