JPS61216895A - Production of powder-cored welding wire - Google Patents

Abstract

PURPOSE:To improve productivity by filling powder into a metallic pipe and subjecting the surface thereof to plating to a prescribed thickness then to drawing at a prescribed value or above of reduction of area. CONSTITUTION:The metallic pipe 2 is formed by extrusion molding, etc. and thereafter the powder 3 of a flux, etc. is filled therein. The pipe is subjected to drawing and annealing, etc. to about 2-8mm outside diameter and is then pickled, further the surface of the pipe 2 is plated with Al or Cu at 0.4-1.5mum thickness. The pipe 2 after plating is subjected to drawing at >=15% reduction of area to prepare the fine powder-cored welding wire 1. The wire is taken up on a reel and is thus made into a product. Since the pipe 2 having a relatively large diameter is subjected to the plating, the plating efficiency is improved and the stage is reduced.

Description

[Detailed description of the invention]

[Object of the invention] (Industrial application field) This invention provides a powder-filled welding wire rod suitable for use in arc welding, in which semi-automatic and fully automatic welding is easily possible. Regarding the manufacturing method of cored welding wire, for example, flux cored wire (FCW) used for CO2 gas arc welding and non-gas arc welding.
) The present invention relates to a method for manufacturing a powder-filled welding wire rod used as a powder-filled welding wire rod. (Prior art) Conventionally, such powder-filled welding wire rods are made by forming a metal tube by sequentially bending a long metal strip in the width direction, and adding flux powder, metal powder, etc. to the inside of the metal tube. Flux powder and / Alternatively, there are seamless ones filled with powder such as metal powder. Among these, the latter seamless powder-filled welded wire rod is 1
For example, it has a cross-sectional shape as shown in FIG. In other words, the powder-filled welding wire 1 shown in Fig. 1 has a powder 3 such as flux powder or metal powder inside a seamless metal tube 2.
It is filled with Such a seamless powder-filled welded wire 1 has problems in that it is difficult to fill the powder and the powder components may become non-uniform. As in the case of powder-filled welding wire rods, air and moisture may enter through the joints and deteriorate the properties of the powder 3, increase the hydrogen content in the weld metal, and the presence of seams may cause the wire rods to deteriorate during welding. There is no problem of deterioration of feedability, and it is excellent in terms of storability, wire feedability, etc. Conventionally, when manufacturing such a seamless powder-filled welded wire rod, a process as shown in FIG. 2, for example, has been adopted. That is, after producing a metal tube 2 with an outer diameter of 15 to 20 mm by extrusion molding or the like, a powder 3 such as flux powder 9 and metal powder is filled into the metal tube 2, and then the area reduction rate is After drawing a wire with a relatively large diameter and necessary annealing to make the outer diameter, for example, about 1.3 mm, pickling is performed, and then the surface of the metal tube 2 is plated with, for example, Cu. A powder-filled welding wire 1 was manufactured by performing light wire drawing of about 1.2 mm to an outer diameter of about 1.2 mm, and this was wound onto a reel. (Problem to be solved by the invention) However, in such a conventional method for manufacturing powder-filled welded wire rods, C
Since U plating is applied, the manufacturing process becomes longer, and plating efficiency cannot be increased due to limitations on the limiting current density during plating, which is a factor that hinders productivity. Since it is a process, the plating efficiency deteriorates as the plating thickness increases. This invention was made in order to solve the above-mentioned conventional problems, and it is possible to omit the wire drawing process and improve production efficiency, and the surface smoothness is extremely good. It is an object of the present invention to provide a method for manufacturing a powder-filled welding wire, which makes it possible to obtain a powder-filled welding wire with excellent wire feedability during welding. [Structure of the Invention] (Means for Solving the Problems) A method for manufacturing a powder-filled welded wire rod according to the present invention involves appropriately drawing, annealing, and pickling a metal tube filled with powder. After that, plating is applied to the surface of the metal tube so that the cross-section reduction rate is 15% with respect to the metal tube.
It is characterized by performing the above wire drawing to obtain a powder-filled welding wire rod with a predetermined outer diameter, and in one embodiment, the plating thickness of the powder-filled welding wire rod is 0.4 to 1.5 μm.
It is characterized in that it is made to be m. The material of the metal tube used in the powder-filled welding wire according to the present invention is not particularly limited, and the powder is not particularly limited, such as a single flux powder, a single metal powder, or a mixture of both powders. It can be determined as appropriate depending on welding conditions and the like. FIG. 3 is a diagram showing the manufacturing process of a powder-filled welding wire rod according to an embodiment of the present invention, and the cross-sectional shape of the manufactured powder-filled welding wire rod can be the same as that shown in FIG. 1. . To explain according to FIG. 3, first, the metal tube 2 is manufactured by a tube-making method such as extrusion molding or roll forming, and then the metal tube 2 is wound around a reel, and powder feeding method using a carrier gas or vibration is performed. A powder 34 consisting of 7 lux powder and/or metal powder is filled into the metal tube 2 by a powder filling method in which 7 lux powder and/or metal powder is added. When the outer diameter of the metal tube 2 is relatively large, such as about 8.0 to 20.0 mm, wire drawing and necessary annealing are performed to reduce the outer diameter to, for example, 2.0 mm.
After adjusting the thickness to 0 to 8.0 mm, pickling is performed. Further, when the outer diameter of the metal tube 2 after filling with the powder is about 2.0 to 8.0II11, it is pickled as is. Next, for example, A411 plating or Cu plating is applied to the surface of the metal tube 2 after pickling. In this case, hot-dip plating or electroplating can be adopted as the plating method, and the plating thickness depends on the powder content after manufacture. More preferably, the welding wire 1 has a thickness of about 0.4 to 1.5 mm. In this way, after plating is applied to the metal tube 2 which has a larger diameter than before, the area reduction rate is 15 OAI.
rrs Suichitci l-l壬--r kL i
X 礒(ad; I-F l')
--Fj degree powder-filled welding wire 1 is manufactured and then wound onto a reel. Therefore, as shown in the above embodiment, plating is performed at a stage where the diameter is larger than in the past, and relatively thick plating is applied, which makes it possible to shorten the process and to make it possible to pass a large current during plating. This makes it possible to improve the plating efficiency, and since wire drawing is performed with a cross-section reduction rate of 15% or more in a state where the plating thickness is relatively large, the smoothness of the surface of the welded wire rod 1 after wire drawing is quite good. Become something. It is more desirable to set the plating thickness at the time of the above plating so that the plating thickness after wire drawing is 0.4 to 1.5 gm.The reason for this is that if the plating thickness is too small, powder will enter. The rust resistance of the welding wire 1 becomes inferior,
This is because it becomes unsuitable for long-term storage, and on the other hand, if the plating thickness is too large, the AM and Cu contents in the weld metal will increase, making it more likely to cause cracks and impeding welding workability. It is. By the way, as mentioned above, the method for manufacturing powder-filled welding wire rods according to the present invention can improve production efficiency to a greater degree than the conventional method. In order to achieve production efficiency greater than or equal to
The wire diameter after wire drawing is do, the wire diameter during plating in this invention method is DP, the speed is Vp, and the speed during wire drawing is V.
o, and when the wire diameter after wire drawing is dO, the results are contradictory: (1) From the conditions based on the wire drawing speed, (2) From the conditions based on the critical current density during plating, the conventional method is more effective than the method of this invention. It is impossible to increase production efficiency. (Example 1) In weight%, C: 0.06%, Mn: 1.00%, St
:O. 20%, P:0. 015%, S2 0.010
%, the balance is Fe, and the outer diameter is 18 m.
After manufacturing a metal tube 2 of m, it is wound around a reel and filled with a powder 3 which is a mixture of a ferroalloy powder such as medium carbon ferromanganese and a nonmetallic powder such as rutile by a feeding method using a carrier gas. The outer diameter of the metal tube 2 is approximately 5.0 m.
The wire was drawn and annealed to a diameter of m, and then pickled. Next, the surface of the metal tube 2 after being submerged is electroplated to a thickness of approximately 4.5 mm. After the wire was drawn at a rate of 94% in area reduction rate, a powder-filled welding wire 1 with an outer diameter of 1.2 mm was produced. Then it was wound onto a reel. In this Example 1, the plating speed was about 700-750
It was possible to manufacture the product at a rate of m/min. Further, the thickness of the Cu plating formed on the surface of the powder-filled welding wire 1 is approximately 0.
, 8 gm. (Example 2) A metal tube 2 having an outer diameter of 5.0 mm was manufactured using the same steel material as in Example 1, and then wound around a reel, and filled with the same powder 3 as in Example 1 using the vibration method. Next, the metal tube 2 was pickled, and then coated with Al to a thickness of about 2 μm by hot-dip plating, and then coated with Cu by electroplating to a thickness of about 4 J.
It was coated to a thickness of about Lm. Subsequently, the metal tube 2 after plating was subjected to continuous wire drawing with a cross-sectional reduction rate of about 94%,
A powder-filled welding wire 1 having an outer diameter of 1°2 mm was manufactured and then wound onto a reel. In this Example 2, the plating speed was about 650-700
It was possible to manufacture the product at a rate of m/min. In addition, the thickness of the Al and Cu plating formed on the surface of the powder-filled welding wire 1 was about 0.9 μm. (Comparative example) A metal tube 2 was made of the same steel material as in Example 1 and had an outer diameter of 18 mm. After manufacturing, it was wound onto a reel and filled with the same powder 3 as in Example 1 using a carrier gas feeding method. Next, the metal tube 2 was drawn and annealed so that the outer diameter was 1.3 mm, and then pickled. Next, Cu plating is applied to the surface of the metal tube 2 after pickling to a thickness of about 0.8 gm by electroplating, and then light wire drawing is performed at a cross-section reduction rate of 14.8% to reduce the outer diameter to 1.8 gm. A 2 mm powder-filled welding wire 1 was produced and then wound onto a reel. In this comparative example, the plating speed was approximately 150-200 m
/min was the limit.

【Effect of the invention】

As explained above, according to the method for manufacturing a powder-filled welding wire rod according to the present invention, after plating the surface of a metal tube filled with powder, the wire is drawn with a cross-sectional area reduction rate of 15% or more to obtain a predetermined shape. Since we are able to obtain powder-filled welding wire rods with an outer diameter, it is possible to omit the wire drawing process, and it is also possible to increase the speed of plating more than before, making it possible to improve production efficiency. It is possible to reduce the manufacturing cost of powder-filled welding wire rods, and because the surface smoothness of the obtained powder-filled welding wire rods is extremely good, it is possible to improve wire feedability during welding. A very good effect is brought about.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of the cross-sectional shape of a powder-filled welding wire;
FIG. 2 is an explanatory view showing an example of the manufacturing process of a conventional powder-filled welding wire rod, and FIG. 3 is an explanatory view showing an example of the manufacturing process of a powder-filled welding wire rod according to an embodiment of the present invention. 1... Powder-filled welding wire rod. 2...Metal tube, 3...Powder.

Claims (2)

[Claims] (1) Powder-filled welding wire material characterized in that a powder-filled welding wire material with a predetermined outer diameter is obtained by plating the surface of a powder-filled metal tube and then drawing the wire with a cross-section reduction rate of 15% or more. manufacturing method. (2) Plating thickness of powder-filled welding wire rod is 0.4 to 1.5μ
A method for producing a powder-filled welding wire rod according to claim (1), wherein m.