JPS61283466A - Torch nozzle for welding - Google Patents

Abstract

PURPOSE:To enable the prevention from the spatter adhesion by containing to a welding torch nozzle the subliming substance gradually subliming and reducing by the arc heat. CONSTITUTION:A torch nozzle is formed by the material blending a subliming substance as the essential component. The subliming substance is the inorganic and organic substance, etc. having the subliming temp. within the prescribed temp. range and reduced with sublimation diffusion gradually by the welding arc heat. The adhesion of the welding hume at the initial time is eliminated thus and therefore no adhesion of the following spatter is caused and the prevention from the spatter adhesion can completely be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Purpose of the invention Industrial field of application The present invention relates to a consumable device for gas arc welding that can prevent spatter generated during gas arc welding of steel materials from adhering to the welding torch nozzle. It concerns the torch nozzle.

Conventional technology Conventional gas arc welding torch nozzle technology includes:
For example, Japanese Patent Publication No. 56-10982, Japanese Patent Publication No. 55-1
For example, Publication No. 0350 is cited. These include copper, ti
4 alloy, aluminum or aluminum alloy, or a torch nozzle in which these are plated or surface-treated with chromium, chromium alloy, etc., is disclosed.

However, these cannot prevent the adhesion of spatter when left as is, and usually a spatter adhesion preventive agent is applied to the surface of these nozzles in advance. Examples include heat-resistant powders such as resins, talc, graphite, metal nitrides, and metal carbides, and these have been used by mixing them with appropriate resins and solvents.

In this type of method, in the case of semi-automatic welding, the worker always holds a torch and frequently removes and coats spatter adhering to the nozzle, and even in fully automatic welding and robot welding, the operator constantly removes spatter adhering to the nozzle. Workers were removing the spatter.

Additionally, due to these problems, torch nozzles made of ceramics or graphite have recently appeared (see Publication No. 52-3380), but these can only be used within a limited range of welding conditions. It cannot be used, and under most welding conditions, spatter cannot be prevented from adhering.

Furthermore, there are consumable torch nozzles that use limestone and rutile (Japanese Patent Publication No. 10218/1982), but the components melt and fall due to arc heat, resulting in rapid wear and tear and poor bead appearance. It has the following drawbacks.

Problems to be Solved by the Invention Welding spatter adheres to the torch nozzle because the welding fume first adheres to the tip of the nozzle or the surface of the spatter adhesion prevention agent, and small spatters of molten iron adhere to it. be. Large particles of spatter gradually adhere to each layer of fume and spatter formed in this way, and finally the spatters are melted together by heat and form a ring shape.

Therefore, the nozzles and spatter adhesion prevention agents conventionally considered could not completely prevent the initial fume adhesion, and as a result, they were not able to completely prevent spatter adhesion.

In other words, it is concluded that the conventional torch nozzles and spatter adhesion inhibitors described above have limitations in their usage conditions. Therefore, spatter deposited during welding automatically falls and enters the bead, causing repeat appearance defects.

In addition, since spatter adhesion cannot be completely prevented in this way,
Particularly in fully automatic welding and robot welding, the operator's hands are required, which is one of the reasons for delaying the introduction of robots and the like in the welding industry.

The purpose of the present invention is to solve the above-mentioned problems.The purpose of the present invention is to prevent spatter from adhering to the nozzle during welding for a certain period of time, and one operator only has to replace the nozzle periodically. The aim is to provide a consumable torch nozzle that requires only a small amount of time.

Structure and operation of the invention The gist of the structure of the present invention is a welding torch nozzle characterized in that it is formed of a material containing as an essential component a sublimable substance that gradually sublimates and decreases due to welding arc heat. .

Means for Solving the Problems In order to achieve the above-mentioned object, the inventors of the present invention repeatedly studied various combinations of sublimable substances and oxidatively decomposed substances and their blending amounts, and found that the sublimation temperature was 100 to 1300. It was discovered that very excellent results could be obtained if the torch nozzle was formed from a material containing a sublimable substance (c) as an essential component.

In the present invention, the sublimable substance has a sublimation temperature of 100-L.
It is a material that can be used as a material for a torch nozzle, and is gradually sublimated and diffused by the heat of the welding arc.

Listed as sublimable substances that can be used in the present invention are inorganic substances such as silicon sulfide, zirconium chloride, zirconium iodide, zirconium fluoride, palladium chloride,
potassium amide, ammonium iodide, tellurium oxide,
Indium chloride, indium oxide, germanium sulfide,
Germanium oxide, gallium iodide, gallium nitride, vanadium fluoride, beryllium fluoride, scandium bromide, nickel fluoride, copper fluoride, zinc sulfide, sodium oxide, calcium cyanamide, zinc oxide, molybdenum chloride, cobalt chloride, titanium chloride , tungsten chloride, etc. In addition, organic substances such as indigo, carbon tetraiodide, tartronic acid, α-amine acetic acid, isonicotinic acid, isophthalic acid, 2-oxyanthraquinone,
-oxyisophthalic acid, 2-oxyterephthalic acid, 1.
Examples include 5-diaminoanthraquinone, 2,7-dioxyanthraquinone, thymine, 3,7-dimethylxanthine, oxyflavone, naphthacene, L-valine, biphthalidylidene, hexabromobenzene, and 5-methyluracil, all of which have sublimation temperatures of 100 to 100. It is desirable to select one with a temperature of 1300'C.

If the sublimation temperature is outside this range, it will be consumed too quickly to be of practical use, or the sublimation will be slow and spatter will adhere before it is consumed, resulting in poor effectiveness.

In addition to these sublimable substances as essential components, the present invention also uses a thermally decomposable compound 1 to control consumption time depending on welding conditions.
For example, metal oxides such as copper nitride, lead carbonate, calcium carbonate, lead carbonate, barium carbonate, calcium magnesium carbonate, rubidium carbonate, iron nitride, graphite, etc. may be used in combination, and CMC, PVA, butyral, methyl cellulose, Of course, resins such as ethyl cellulose, alkyd and acrylic, and binders for ceramics such as PEG may also be used.

In addition, in the present invention, one or more of the various substances listed above are used as sublimable substances, and if necessary, the above-mentioned pyrolyzable substances are used in combination to form the torch nozzle. By appropriately blending a sublimable substance with a high sublimation temperature and a sublimable substance with a low sublimation temperature, the consumption time can be controlled. In other words, it is possible to use a torch nozzle whose sublimation speed is set to suit the target welding conditions.

In this way, in the present invention, since the nozzle itself is sublimated by the welding arc heat, the adhesion of the fume itself, which causes the above-mentioned problem, can be prevented, and the adhesion of spatter, which is the next step, can also be naturally prevented.

It goes without saying that not all of the torch nozzles in the present invention necessarily have consumable properties; for example, only the tip of the torch nozzle may be designed to have sublimation properties.

Example 1 Indium oxide and ammonium iodide in a weight ratio of 1:1
The mixture was mixed in the following proportions, molded into a torch nozzle, and welded using this torch nozzle under the following conditions to examine the degree of spatter adhesion to the nozzle.

The degree of adhesion of spatter is determined by the time it takes until the nozzle tip wears out and normal welding is no longer possible, or until the spatter adheres to the nozzle tip and normal welding is no longer possible (inner diameter 1
It is expressed as the cumulative arc time (until the nozzle diameter of 6 mm becomes 12+a+).

Comparative Example a was tested under the same conditions using an untreated pure copper chrome plating nozzle, and Comparative Example A was a test in which a mixture of silicon carbide and resin with a sublimation temperature of 2000°C was applied to a pure copper chrome plating nozzle. It was tested in the same manner.

Welding conditions Welding method Carbon dioxide automatic welding Welding current 300A Arc voltage 30V Welding speed 400 tam/min Wire
Diameter: 1.2+mm Gas flow rate: 20 i/min Downward fillet welding Welding was repeated in a cycle of arc for 10 seconds and pause for 1 second.

Table A shows the cumulative arc time results measured in the above tests.

Table A As shown in Table A, the nozzle of the present invention provides a longer arc time than untreated nozzles or nozzles coated with high-temperature sublimate, and there is no spatter adhesion during this approximately one hour period. Of course, welding can be done without having to remove it.

Example 2 A torch nozzle was molded from a material in which potassium amide and calcium carbonate were mixed at a weight ratio of 1:1. Welding was performed using this torch nozzle under the following conditions, and the cumulative arc time was measured in the same manner as in Example 1.

As a comparative example, a nozzle made of calcium carbonate alone was tested under the same conditions.

As a comparative example, a nozzle molded solely from indigo, a sublimable substance, was prepared and tested in the same manner.

Welding conditions Welding method Carbon dioxide automatic welding Welding current 45OA Arc voltage 46V Welding speed 450 tan/min Wire
Diameter: 1.6 mm Gas flow rate: 25 m/min downward fillet welding Welding was repeated in a cycle of arc for 10 seconds and rest for 1 second.

Table B shows the cumulative arc time results measured in the above tests.

Table B As shown in Table B, the nozzle of the present invention produced excellent results even in welding at high currents where spatter is extremely common.

In other words, if a thermally decomposed substance such as calcium carbonate is used alone, spatter cannot be avoided because of the adhesion of fume. In other words, by using a substance with a sublimation temperature within a certain range as in the present invention, the sublimation property prevents spatter from adhering to the material, allowing automatic welding without the operator having to remove spatter during welding within a certain period of time. This allows you to do other work away from the machine or welding robot.

It should be noted that when indigo in the comparative example was used alone, the sublimation was a little faster under conditions of large current, and the arcing time was a little shorter, but no spatter was observed at all.

C. Effects of the Invention As explained in detail above, the present invention is a welding torch nozzle in which a sublimable substance is formed as an essential component. There is no adhesion of welding fume during the welding process, and therefore subsequent adhesion of spatter is naturally impossible, and spatter adhesion prevention properties are completely achieved.

Furthermore, by blending a thermally decomposing substance with this sublimable substance, or by using two or more types of sublimating substances in combination, it is possible to freely adjust the sublimation conditions and consumption time of this torch nozzle.

As a result, it is only necessary to replace the nozzle at predetermined intervals, and there is no need to constantly monitor it as in the past, resulting in extremely high workability, making it easy to fully automate and robotize welding. This will enable it to be implemented and introduced.

Claims (1)

[Scope of Claims] 1. A welding torch nozzle characterized in that it is made of a material containing as an essential component a sublimable substance that gradually sublimates and decreases due to welding arc heat.