What is argon arc welding

Argon welding of non-ferrous and ferrous metals

Argon welding is an integral technological process in many production and repair enterprises. In the environment of this gas, non-ferrous metals such as copper, aluminum, duralumin and cast iron are welded; steel and other ferrous metals are also successfully welded.

Under normal conditions, without gas supply, many pores are formed, the metal oxidizes, making the connection fragile and short-lived. Argon protects the welding zone from the penetration of contaminated air into it, eliminating the formation of defects.

Features of argon welding

The peculiarities of argon welding include the fact that any metals, not only non-ferrous ones, can be welded in a gas environment. Ordinary steel is not critical to oxidation, but in an inert gas environment the weld is of better quality.

Basically the process is identical as in the case of a conventional arc or semi-automatic with wire feed. The difference is technology. To obtain an ideal result, apply the melt intermittently, grabbing a centimeter at a time. This makes the molten metal flow better.

Argon-arc welding, depending on the method and speed of the process of joining two parts made of non-ferrous metals, is divided into 2 types:

Both types are made with consumable or non-consumable electrodes. In the second case, filler wire or rod is also used, depending on the thickness of the parts being welded.

At modern enterprises, automatic argon-arc welding is actively used, because it allows you to obtain high-quality seams in a fairly short time with a thickness of no more than 1 cm and strictly in accordance with GOST.

A wire made of a similar alloy is used as an electrode, which is automatically fed to the welding site. At the same time, argon is supplied, which protects the welding site from oxidation and the formation of shells.

This method is convenient because you do not have to change the electrode every time.

Argon-arc welding is also performed using special consumable electrodes. They are made from tungsten. When choosing them, you need to pay attention to the percentage of additional components, since there are no universal ones. There are different types of them on sale depending on the type of materials being welded.

Argon-arc welding with non-consumable electrodes is also used, as shown in the photo. They are made of tungsten, a metal that has a high melting point, so it does not melt in the spark zone. It is used to heat the filler material supplied to the joint.

The table below shows the main types of such electrodes designed to work with various metals.

Designation Composition Materials to be welded

WP (green)	99.5% tungsten	Aluminum, magnesium
WY (dark blue)	Ytriated, up to 2.2% oxide additive	Niobium, tantalum, molybdenum, titanium, nickel, copper, bronze
WL-20, WL-50 (blue, green)	Added lanthanum oxide	High alloy steels, copper, aluminum, bronze
WZ-8 (white)	Contains zirconium oxide	Aluminum, bronze, magnesium, nickel
WT-20 (red)	Contains thorium oxide	Stainless steels, molybdenum, tantalum, copper, silicon bronze, nickel, titanium

Argon welding technique

The principle of welding non-ferrous metals using the argon-arc method is based on the creation of an electrical discharge between a consumable or non-consumable electrode and the surface to be welded. The electrode is placed in a ceramic nozzle, into which argon is also supplied. All this is in the holder.

If a non-consumable electrode is used, then filler wire is fed into the melting zone or bath at the same time. The inert gas, being lighter than oxygen, displaces it, which eliminates nitriding and other undesirable processes. Nothing is applied to the filler material, so it is potentially safe. Once in the welding zone, it melts together with the parts being joined, forming a single homogeneous connecting seam.

In order for argon-arc welding to be of high quality, and for the joint of parts to be strong and uniform, it is necessary to follow the technology for performing the work. You should also apply the correct voltage to the electrode. High-frequency and high-voltage pulses are applied to it, due to which the gap between it and the part is successfully ionized, due to which an arc is formed.

Many are sure that it is formed upon contact, but this is not true. It is thanks to the preliminary ionization of the gas in space that such a high purity of the weld and its uniformity are achieved. These pulses are generated at the electrode by a special device called an oscillator. It is connected to the DC power supply circuit from the welding transformer.

The peculiarity of the oscillator is that it makes it possible to qualitatively weld parts using alternating current. This is achieved due to its work as a stabilizer in moments of negative polarity. This process ensures reliable and stable arc burning.

The argon arc welding technique is as follows:

1. The master prepares the parts to be joined. Removes edges from one or both sides, or leaves a gap between them, cleans the surface of oxide and dirt with a wire brush.
2. After preparing the parts, the worker turns on the argon-arc welding machine and brings the torch to the part without touching it with the electrode.
3. Next, you need to turn on the gas supply from the cylinder and pulses to the electrode to form an arc.
4. As the spark burns, the worker supplies filler material.

Welding using this method should be done spotwise so that the so-called pool has time to form. When welding vertical seams, it is necessary to move from bottom to top. The detailed process of welding parts can be viewed in the video.

Argon welding modes

To obtain a high-quality welded joint of non-ferrous and ferrous metals, it is necessary to correctly select argon-arc welding modes. This is done based on experience and can also be found in reference tables. Accordingly, the equipment must be able to change the current to suit specific needs.

Selecting current and polarity

To weld non-ferrous metals in an argon environment, a current of constant or alternating polarity is used. In no case should you work with its inverse value, because in the process difficulties will arise associated with poor arc burning and excessively high voltage.

Charged particles move towards a positive potential, so the electrode will heat up more and burn out faster.

Current selection

The choice of current value for welding is based on three main factors: the type of current, the diameter of the electrode and the thickness of the parts being welded. In order not to keep all these numbers in your head, let's make a table. It describes all the values ​​depending on certain criteria.

Electrode diameter (mm) Alternating current (A) Direct current (A)

1 – 2	20 – 100	65 – 160
3	100 – 160	140 – 180
4	140 – 220	250 – 340
5	200 – 280	300 – 400
6	250 – 300	350 – 450

Voltage

For high-quality welding of parts of various thicknesses when using argon-arc welding, it is recommended to set the voltage to no more than 14 V. With this value, an arc length of about 1.5-3 mm is ensured, which is the optimal value. It also ensures good penetration depth, which is the main criterion for the strength of the connection between parts.

Welding speed

It is purely individual, so it is chosen by the master on the spot. The main thing is not to rush, because welding non-ferrous metals is very capricious.

Argon quantity

Also, along with the choice of electrode diameter, the flow rate of the supplied shielding gas is also calculated. This is done based on the type of metal from which the parts being welded are made, the thickness and width of the seam. This is determined in practice.

Distance from electrode to part

It depends on the thickness of the metal being welded and the method of joining it. For example, for a butt connection, 3-5 mm is enough. If parts are welded at an angle, then the recommended distance should be at least 0.5 cm and no more than 8 mm.

Advantages and disadvantages

Argon-arc welding has both features and disadvantages. Of course, there are more positive aspects to it, and they are as follows:

• You can weld not only copper and aluminum, but also steel.
• The seam is neat from an aesthetic point of view, subject to the technique of feeding the rod and applying the arc.
• Argon-arc welding of non-ferrous and ferrous metals can be done at home with your own hands if you have the necessary equipment and consumables.
• The connection is strong throughout the entire depth of the joint if the parts have been well prepared in advance. The chamfer was removed at an angle of 45 degrees, a gap was provided and the oxide film was removed from the surface.
• In this way, you can weld thin parts without penetration and other undesirable defects.
• When automating the welding process, it is performed not only efficiently, but also quickly.

The disadvantages include:

Complexity of the process. Without the right equipment, you will not be able to perform high-quality welding. In addition, it is necessary to have some experience in order to correctly feed the bar and control the arc. Therefore, a beginner in this matter will have to learn a lot.

Also, the price of professional equipment will be quite high, but you can assemble the components separately, which will be somewhat cheaper.

Types of welding equipment

Argon arc welding is a special method of joining parts made of different metals, which allows us to obtain a high quality weld, its attractive appearance and strength. Therefore, special equipment is required to perform such welding work. There are several varieties of it on sale, depending on the level of mechanization:

• For manual. There are a lot of machines on sale for welding with consumable and non-consumable electrodes.
• For mechanized welding, wire welding in an argon-arc environment is mainly used.
• For automated processing, devices with automatic supply of filler material are used and installed in production facilities.
• For robotic welding, special devices are used that not only feed the wire and control the arc burning process, but also control the welding.

The cost of the equipment will depend on the intended purpose and scope of use.

The equipment for manual welding includes:

Source: https://svarkaspec.ru/svarka/vidy-svarki/svarka-argonom.html

Advantages and features of argon welding

You are probably familiar with the problem of high-quality welding of special types of metal, such as aluminum, copper or non-ferrous metals. With standard electric welding using electrodes, you will not be able to weld a reliable seam, this is due to the characteristics of the metal and its properties. In such cases, experienced craftsmen are looking for another welding method, and welding in an argon environment comes to their rescue.

What is argon welding and what is the principle of operation? What are the pros and cons of this welding method and how to properly weld metal with argon? In this article we will answer all your questions.

general information

Argon-arc welding - what is it? How does argon welding work? This is essentially the same welding as all the others, the only difference is that the process takes place in an argon environment. Argon is a gas stream that is directed into the welding zone during welding.

Below you can see a diagram of welding using argon. Argon, like any other gas, performs a protective function during welding: it prevents metal oxidation, improves the quality of the weld and speeds up work.

Argon for welding, directed into the welding zone, forms a kind of “Dome”, preventing oxygen from negatively affecting the quality of the seam.

Various special metals, such as titanium, can be welded using argon welding. In this work, you can use consumable and non-consumable electrodes and tungsten wire. Tungsten wire is often used when welding dissimilar metals. Welding is carried out both manually and automatically.

Manual argon welding (RAD welding) is the most common and inexpensive type of argon welding. If RAD welding is selected, it is advisable to use a non-consumable electrode.

There is automatic argon welding using a consumable and non-consumable electrode (labeled AADP and AAD, respectively). We will not claim that manual welding is better than automatic welding or vice versa.

Ultimately, each welder decides for himself which method is preferable for him when performing certain jobs.

Equipment

Several types of welding equipment are used for argon welding. This can be a manual method, when the master holds the torch with his own hands and feeds the wire into the welding zone, or an improved manual method, when the wire is fed using a special device.

There is also equipment with which automatic argon arc welding is carried out. The torch and wire are fed into the welding zone automatically; sometimes the welder does not even need to monitor this process; he can be replaced by a special operator. Expensive industries can use robotic equipment that does not require human presence. A program is pre-loaded into the machine, according to which the robot performs welding.

Now let's get down to business. We will tell you how to weld with argon welding so that the work turns out to be of high quality and durable.

How to cook in argon

What is needed for proper welding? Of course, a little theory and a lot of practice. We will tell you the theory, but you will have to do the practice yourself. The more you practice, the faster you can start doing serious work. In the meantime, let's find out what the technology of argon arc welding is and what needs to be taken into account so as not to make mistakes.

First of all, you need to thoroughly clean and degrease the joints of the parts to be welded. Even if there is visually no dirt or corrosion, you still need to clean the metal surface. While working, try to shorten the length of the welding arc. The fact is that a long arc forms a wide, shallow seam. The quality of this connection leaves much to be desired.

Therefore, when working with a non-consumable electrode, try to make the arc as short as possible, bringing the rod closer to the metal surface. But this may not be enough to make the seam narrow and deep. Move the electrode longitudinally without deviating to the side or performing transverse movements. It is for this reason that the welder must have a “steady hand” when welding with argon, otherwise the slightest deviation can lead to deterioration in the quality of the welded joint.

The filler wire and electrode should only be placed in the welding area. If you constantly move the rod or wire to the side, you will break the protective properties of argon and oxygen will penetrate into the weld pool. The wire should be fed smoothly and evenly, avoiding sudden feeding. Otherwise, the metal will spatter heavily and deteriorate the quality of the weld.

At first, many craftsmen (especially beginners) find it difficult to understand at what speed to feed the wire. Unfortunately, there is no single norm that will solve this problem. Everything is learned with experience, so experiment. The additive wire must be fed at an angle and in front of the rod. These requirements are mandatory. Failure to comply with them leads to the formation of an uneven seam and complicates the welding process.

It is also not recommended to abruptly start or end the welding process, since unnecessary oxygen is guaranteed to enter the welding zone. We recommend feeding argon welding gas into the welding zone for 20 seconds before starting work.

If you plan to finish welding, first remove the wire, then turn off the torch. This process should take about 10 seconds. Also, when finishing welding, reduce the amperage.

If you don't do this and simply remove the wire and torch, oxygen will enter the welding area.

As you can see, argon welding requires a lot of patience and at least minimal experience. You can evaluate your work using the penetration indicator. Inspect the seam you made: it should not have a round, convex shape.

If the seam looks like this, it means that it is not fused. In this simple way you can check the quality of the seam and evaluate its strength characteristics.

Of course, this method cannot replace full-fledged quality control using instruments, but you will be able to see the shortcomings of your work at the initial stage.

Welding mode setting

Now that we have figured out how argon welding works, let’s take a closer look at choosing a mode. The quality of the welded joint also greatly depends on this. To choose the right mode, you need to practice a lot and carefully study the theory. We've put together some tips for choosing the right welding mode that we hope will help speed up your learning curve.

So, the welding mode is essentially a choice of the polarity and direction of the current. The choice of welding mode depends on the individual characteristics of the metal (or metals) to be welded. If you need to weld steel structures, set the polarity to straight and constant current. If you need to weld aluminum and its alloys, use direct current and reverse polarity.

It is also important to set the current correctly. This parameter is adjusted based on the thickness of the metal, the diameter of the electrode and the polarity you set. All these parameters are interconnected. Many craftsmen learn through practice what current value needs to be set to perform specific tasks. But we recommend that you first use special tables, one of which you can see below.

We said earlier that a high-quality seam is obtained if the arc is short. The same applies to arc voltage. By the way, do not forget about gas consumption in an argon environment. If you work in production, then you will need to monitor this indicator. To reduce consumption, it is better to create a laminar gas flow. Laminar flow is when gas moves uniformly and does not mix or pulsate.

Advantages and disadvantages

Pros:

• There is no need to heat the joints very much, so the parts are not deformed under the influence of high temperatures.
• Argon gas for welding is called inert, which means that it is heavier than air, so if the technology is followed, oxygen will not penetrate into the welding zone.
• Arcs have high thermal power, so with proper experience, work can be done quickly and efficiently.
• Despite the many nuances, the welding process is not as complicated as it seems, and it can be learned quickly.
• You can weld metals that cannot be joined with other types of welding.

Minuses:

• It is not recommended to weld outdoors if there is a strong wind outside. Some of the gas evaporates, causing the weld to become of poorer quality. Carry out welding in a closed workshop or garage with forced ventilation.
• At first, it is difficult for beginners to correctly set up the equipment and conduct an arc.
• If you plan to use a high-ampere welding arc, then you need to think in advance about how you will cool the seam.

Instead of a conclusion

Now you know what argon welding is and how to introduce it into your work practice. Argon arc welding has a very important advantage - it allows you to connect parts that are simply impossible to connect under other conditions.

And such a need may arise not only in large-scale production, but also at home or in the country (for example, when welding pipes). But remember: theory without practice does not work. Try to practice your skills on test samples as much as possible before moving on to more serious tasks.

Tell us about your experience with argon welding in the comments and share this material on social networks. Good luck!

Source: https://svarkaed.ru/svarka/vidy-i-sposoby-svarki/gazovaya-i-gazozashhitnaya-svarka/osobennosti_svarki_argonom.html

Argon welding - features, technique, principle of operation

Often there is a need to weld materials that cannot be joined with conventional types of welding, for example, aluminum, copper, titanium, and so on. Therefore, in order to create a durable one-piece structure from these metals, argon welding is used. What is argon welding and how does it work? These and other questions are answered in this article.

Features of argon cooking

The process - argon arc welding occurs in an environment of inert gas argon, hence the name of the welding process. The use of argon in welding when joining two metals is a protection against oxidation that can occur due to contact with oxygen in the air. That is, argon covers the welding zone and prevents oxygen from penetrating into the area of ​​the mating surfaces.

The welding mode itself can be performed manually, semi-automatically and automatically. There is a classification of modes that depend specifically on the methods described above and the type of electrode involved in the welding process. Two types of electrodes: consumable and non-consumable. The second type includes tungsten wire, with which you can guarantee a strong and reliable connection between two metals, even dissimilar ones.

So, classification of argon arc welding modes:

• Manual welding with argon, where a non-consumable electrode is used - its marking is RAD.
• Argon welding is automatic, where a non-consumable element is used - AMA.
• Automatic argon arc welding, which uses a consumable electrode - AADP.

Operating principle of welding equipment

The welding equipment includes:

• A welding machine of any type for arc welding with an open circuit voltage of 60-70 volts.
• Power contactor, with the help of which voltage will be supplied from the welding machine to the torch.
• Oscillator. This device converts a mains voltage of 220 volts and an oscillation frequency of 50 Hz into a voltage of 2000-6000 volts with a frequency of 150-500 kHz. These electric current parameters make it easy to ignite the arc.
• A device for blowing the welding zone with argon.
• Ceramic burner.
• An argon cylinder is connected to the burner through a reducer and a hose.
• Non-consumable electrode and filler wire.

You can watch a video on how argon welding works, but this is the principle. First, the welding mode is adjusted and the metals being joined are cleaned. The torch is taken in the right hand, the filler wire in the left, it is not connected to electricity. There is a special button on the torch handle with which you can supply protective gas to the welding zone. The gas supply is turned on 20 seconds before the start of welding work.

The burner must be lowered so that there is a small distance between the non-consumable electrode and the surfaces to be welded - within 2 mm. By the way, the electrode is inserted into the burner in such a way that an end no longer than 5 mm protrudes from it. There is a latch inside the burner into which an electrode of any diameter can be inserted.

The welding machine is turned on and voltage is supplied to the electrode. An arc appears between it and the metals being joined. At this time, argon is supplied from the burner nozzle, which covers the welding zone. The welder feeds filler wire into the welding joint, which melts under the action of an electric arc and covers the gap between the parts. In this case, a slow movement is made along the seam.

Do not ignite the electrode by contacting it with the metals being welded. An oscillator is specially used for ignition, as shown in the video.

What is argon arc welding? Principle of technology

All our lives we are accompanied in everyday life by things made of various alloys and non-ferrous metals.

Remember how many times you were looking for a way to connect together, broken into several parts:

• antique item;
• a burst stainless steel container;
• a leaky saucepan from your beloved mother-in-law;
• and much more.

Argon welding will help you solve these everyday issues. Of course, argon welding performed by professionals will be of excellent quality. But the high cost of such a service puts the repair of necessary utensils on hold until better times.

This is where the average person asks: is it possible to use argon arc welding at home and what will be needed for this?! Yes, friends, a home craftsman can do this, and if you have experience in arc welding, then there will be no problems with argon.

General concepts

Argon arc welding - what is it?! The technology uses an electric arc and gas. This hybrid is an electro-gas combination of metals.

It’s clear with an electric arc: it melts the edges of the material being welded and connects them.

But argon is designed to protect the welding site from harmful impurities and gases, i.e. it displaces oxygen from the working bath and isolates the welding site from exposure to the atmosphere.

Why is this necessary? When joining non-ferrous metals and alloy steels, oxygen has a bad effect on the quality of the seam, and aluminum even catches fire. To solve such problems, they use argon gas, which is 38% heavier than air.

The gas supply occurs in advance, before ignition of the arc, and stops after completion of the welding operations.

Due to the lack of reaction in the area of ​​the working area, argon is called inert.

Argon welding is performed with a consumable or non-consumable tungsten electrode. It is not for nothing that in old electric ovens a tungsten spiral was used for cooking, due to its refractoriness.

Electrodes are produced in different diameters and materials for each type of metal being welded.

The variety of welding technology is divided into 3 types:

1. RAD - manual argon arc welding with a non-consumable electrode;
2. AMA - automatic connection with a non-consumable electrode;
3. AADP is an automated consumable electrode process.

Principle of technology

Consider the RAD technology - the welder's hands hold the torch and filler wire.

Before work, clean the surface of the products to be connected and attach the wire to ground. We take the torch in one hand and the wire in the other and bring the equipment to the surface of the metals at a distance of 2-3 mm. We turn on the gas supply with the button on the burner 15 seconds before the current supply.

After a certain time, an electric arc will appear between the electrode and the metal, which melts the edges of the products and the wire. By slowly moving the torch along the seam and feeding the filler wire, we get a beautiful and reliable connection (not always).

You can't do without skill here. The wire must be held in front of the burner at an angle. With trial and error, you can master the technology!

Watch the video on how to cook with argon correctly:

overview of the main TIG welding applications and fixtures:

About consumable electrode welding

For connections in argon with a consumable electrode, special installations and apparatus are used. Welding occurs using a special torch equipped with a small electric motor that feeds wire from a spool.

review of the semi-automatic Tesla MIG MAG MMA 300 designed for consumable electrode welding:

Advantages and disadvantages of the method

What are the pros and cons of argon welding? Flaws:

• the equipment is difficult for beginners;
• welding work requires experience and skill;
• with the manual method, the speed of work is low.

Advantages:

• the weld seam is protected from atmospheric influences;
• heating of the metal is weak, the experimental product does not change shape;
• possibility of joining any alloys;
• the scope of application is limitless;
• rare replacement of electrodes.

Know that the price per centimeter of argon welding across the country ranges from 30 to 300 rubles and the fact of owning the device can also be considered an advantage.

Why is there such a significant difference in price per cm? Depends on the quality of equipment, material and the greed of companies providing such services.

Results

Let's summarize: now you know what it is - argon arc welding? And if you have to carry out welding work quite often, then it’s worth purchasing such equipment!

(1 5,00 out of 5)

Source: https://plavitmetall.ru/svarka/argonom-argonodugovaya-oborudovanie.html

Argon welding: the essence of the method, advantages and disadvantages, equipment and materials

You may have heard about the peculiarities of cooking certain types of metal, for example, aluminum, copper and other non-ferrous metals.

Using classic electric welding using an electric current conductor, you will not be able to achieve a strong connection.

This is influenced by the characteristics of the material. Then experienced specialists resort to another method of work and use argon arc welding.

What does argon connection mean and how does it work? What positive or negative qualities are present in argon welding and the specifics of welding metal with argon? Let's discuss this point in detail.

Basics

What is included in argon arc melting? What are the specifics of this method? It can be applied to all types of welding, but the only difference is that it is necessary to work in the field of argon.

The argon sphere is a gas flow that comes in when the elements are welded by the inverter. The following is a drawing of a device operating in an argon environment.

This gas, like others, acts as a protection during welding: it prevents the metal from oxidizing, increases the efficiency of seam production and reduces time consumption.

The cooking gas directed to the area creates a kind of “lid” that prevents the flow of oxygen, which worsens the performance of the seam.

Welding in an argon environment allows you to weld metals like titanium. For soldering, electric current conductors with or without the possibility of melting, as well as tungsten wires, are used.

Tungsten wire is mainly used in welding various metals. You can cook either manually or using automation.

Manual argon welding is one of the popular and frequently used types of argon welding. When choosing welding in argon, it is better to use a current conductor that is not capable of melting.

There is automatic welding in an argon environment, which uses a current conductor that can and cannot melt.

It is impossible to say for sure which welding is better - manual or automatic. In the end, each master individually selects the most convenient method for himself when performing tasks with such a device.

Device

To work in an argon environment, various welding devices are used.

The choice may fall on a manual control method, in which case the specialist himself holds the torch and supplies a metal wire to the welding area, or an improved portable method, when a metal wire is fed into the device.

There are also devices powered by electronics and cooked under the influence of argon. The torch and metal wire are supplied to the welding area automatically; sometimes the master does not need to control what is happening; a master is provided for this.

In mass production, robotic devices are used that independently control the process. They are directly programmed to perform argon welding tasks.

Let's get to work. We will explain the use of a welding machine when working in an argon environment, so that the result will satisfy you and serve you for many years.

What techniques to use for working in an argon environment

What do you need to know to get started? It is important to know the theory and develop practical skills. We will explain the theoretical part, but you need to practice it yourself.

With more practice, you will soon be able to take on more complex tasks. First, we will analyze the methods of cooking in an argon environment and what you need to know in order to make as few errors as possible.

First, you need to thoroughly clean and degrease the edges of the parts that you will weld. Even if at first glance everything is clean and free of rust, you still need to clean everything.

During operation, do not make the welding arc long. The reason for this is that the welding arc creates a thick surface seam. This cannot be considered good quality.

This is the reason that with an electric conductor that does not melt, it is better to use a shorter arc when bringing the rod to the product. This may not be enough for a narrow and deep seam.

Move the current conductor longitudinally, without tilting away from the part, without making transverse movements. This is why the master must hold his hand firmly when working in an argon environment, because this is what gives high-quality contact when welding with argon.

The metal wire for soldering and the electrical conductor must be placed in the argon welding area. If you do not hold the rod or metal wire accurately, the quality of the gas may be affected and oxygen will enter the welding area.

The metal wire must be applied with progressive movements and slowly, avoiding sudden application. Otherwise, metal particles will begin to splash, which will worsen the final result.

Selected recommendations

Many welders (especially beginners) do not initially know how quickly to apply metal wire. Unfortunately, there is no standard under which this problem will be solved.

These skills are developed through practice, so try and find the techniques that suit you. The metal wire for the additive must be applied at an angle to the rod.

These rules must be strictly followed. In the absence of such actions, it may turn out that the joint turns out to be crooked and it will become more difficult to correct it.

At the same time, it is undesirable to quickly start work and stop it, this will lead to excess air entering the welding area. We recommend directing gas into the work area for half a minute and only then starting to work.

If you need to stop the process, then remove the metal wire and then turn off the burner. All these steps will take approximately 9 seconds.

Also, towards the end of execution, reduce the supplied current. If you don't do this and just pick up the metal wire and the torch, oxygen will have access to the welding area.

From this it is clear that cooking in argon must be patient and have at least a little skill. Use penetration indicators to evaluate your work. Look at your seam: it should not have any bulges or roundness.

If they are, it means you didn’t melt it well. This is a simple method to determine the quality of the seam made and how durable it is.

This method, of course, does not equate to quality control carried out by the device, but you can immediately see where errors were made in the work.

Setting up the welding system

After we have explained how argon welding works, let's look at the argon arc welding system itself and what mode it should be set to.

To properly set up the device, you need practice and decent knowledge of theory. We have several recommendations regarding the correct setup of the cooking device and, perhaps, they will help you learn faster.

The welding mode is, in principle, the selection of the polarity and direction of the current. The welding mode is selected according to certain properties of the metal used for welding.

If it is necessary to weld metal structures, then set direct polarity and non-alternating current. For welding aluminum and its alloys, choose non-alternating current and reverse polarity.

It is important to set the voltage. It is set based on the thickness of the material, the width of the current conductor and the selected polarity. They are all connected.

Many welders already know from experience what current strength should be selected for a certain type of work. We recommend using special tables at first, one of them is given below.

We have already mentioned that a good quality seam can be made using a short arc. The arc current strength will also be short for a long time. Also, do not forget about the amount of gas when working.

It is important to monitor this indicator while working in production. To reduce consumption, it is advisable to make an irrotational gas supply. Irrotational is the uniform movement of gas, not pulsating or mixing.

Positive and negative sides

Positive:

• There is no need to heat the connection too much so that the parts do not change shape due to heat.
• Argon is an inactive welding gas, so air is lighter than it. This prevents oxygen from penetrating into the soldering area.
• The arc is resistant to elevated temperatures, so experienced specialists perform this work quickly and accurately.
• Tig welding is not that difficult, so it is easy to learn how to do.
• Suitable for welding metal elements that are not suitable for other types of soldering.

Negative:

• It is not advisable to cook outdoors, especially in windy weather. Gas particles are sprayed, this leads to the fact that the welding seam is not very smooth and clear. It is better to cook in a closed space with good ventilation.
• Inexperienced craftsmen will initially find it difficult to set the necessary device settings and conduct an arc.
• When using a high amperage welding arc, it is advisable to first consider what methods will be used to cool the weld.

Conclusion

We told you what argon arc welding is and its application in practice.

Argon arc welding has such a property that it can be used to solder structures that cannot be joined under other conditions.

This may be needed not only in large-scale production, but also at home.

It is important to remember: theory is not enough for quality work; you need to practice a lot. You need to train more before starting to cook serious structures.

Share your experience of argon cooking in reviews and tell us about what you learned from us on social networks. Good luck in your work.

Source: https://prosvarku.info/tehnika-svarki/svarka-argonom

Argon welding - technology features

If conventional welding is not suitable, electric arc welding or argon welding is used. What is its purpose, application features, basic technology, required welding equipment, advantages and disadvantages? The article will be of interest to anyone interested in welding stainless steels and non-ferrous metals.

What is argon welding and what is it used for?

Electric arc welding in a shielded gas environment is used when it is necessary to isolate the process from interaction with atmospheric air. The most popular and effective is the inert gas argon. The process using it is called argon arc welding or, in common parlance, argon welding.

It is used for welding products made of aluminum, titanium, copper, stainless steels - metals and alloys that actively oxidize or contain elements that are actively oxidized by atmospheric oxygen.

Why is argon used - its comparison with helium

Argon, as already mentioned, is an inert gas. It does not react chemically with anything, which is especially important at temperatures above a thousand degrees Celsius in the welding zone.

Another inert gas, helium, has a similar property. It costs much more than argon, so it is used only in special cases. Argon has a specific gravity 38% greater than air. Due to this, it well insulates the welding site and protects it from oxidation.

Helium under similar conditions requires the supply of gas under high pressure to the high-temperature zone and, accordingly, a higher consumption of protective gas.

Due to the different ionization potential, the voltage of an argon arc is lower than that of a helium arc. Its heat generation is less, which means the penetration zone is smaller and the cross-section of the weld is smaller. Unlike helium welding, argon welding forms a long and narrow finger-shaped seam. At the gas-liquid interface, argon has a higher surface tension. As a result, the seam bead is higher with sharp transitions from the base metal to the seam.

Features of the weld seam in argon arc welding

The greater the angle between the surface of the base metal and the weld, the greater the stress concentration in the welding zone. If the joint has sufficiently high requirements for equal strength, it is necessary to grind off the seam bead after welding

With the correct choice of electrode material or additive, welding mode and method of protection, the weld metal is usually softer than the base metal due to a smaller amount of impurities. To ensure strength, it is required that the “soft” zone be as narrow as possible. Welding is more difficult to perform technologically, but avoids the need to strengthen structural elements at the joint.

There are two main technologies used for argon arc welding: TIG welding and MIG welding.

TIG – non-consumable electrode welding

The arc burns between a refractory tungsten electrode and the workpiece. The filler metal rod is fed into the welding zone manually.

The non-consumable electrode welding process has its own characteristics. It is better to ignite the welding arc with straight polarity, when the electrode is the cathode. It is given a sharp sharpening at an angle of 45 - 55 degrees.

This is necessary to obtain a narrower welding arc and narrow the penetration area. The narrower the zone you need to get, the sharper the sharpening should be. It is not recommended to light an arc on the metal being welded, so as not to melt or contaminate the tip of the electrode.

It is better to perform this operation on an auxiliary carbon (graphite) plate.

The polarity of the process should be selected depending on the metal of the parts being welded:

• Stainless steels are better welded with straight polarity.
• Aluminum and its alloys - on reverse or more often on alternating current. This is due to the fact that when the cathode is a part, refractory oxide films formed on the surface of aluminum are better removed from the welding zone. But when the cathode is a part, instability of the emission spot appears because the combustion zone of the welding arc moves to the cold area. Therefore, not just alternating welding current is needed, but high-voltage pulses during periods when the cathode is located on the part.

The welding torch with a tungsten electrode is held at an angle of about 80° to the seam, back to the direction of movement. Filler rod - in front perpendicular to the electrode.

There must be a gap between the parts being welded. The exception is when the parts lie on a copper or steel substrate. Argon is supplied through a nozzle surrounding the welding electrode.

Unlike the usual zigzag or crescent movements made by a coated electrode, tungsten is carried out in a straight line, without deviating from the seam line. This is necessary so that the area of ​​molten metal does not leave the zone protected by argon. The speed of the welding process should not be high so that argon has time to penetrate through the gap between the parts being joined to the back side of the weld.

It is important to maintain a stable distance between the electrode and the workpiece. This is necessary for constant voltage and heat generation of the welding arc. The size of the penetration area, the shape and quality of the weld directly depend on this.

The process must begin 10 - 15 seconds after the supply of argon, so that the molten metal is guaranteed to be protected from interaction with atmospheric oxygen.

At the end of the process, the welding current should be reduced gradually to avoid the appearance of a crater at the end of the seam.

After the arc goes out, argon must be supplied for another 10–15 seconds until the metal cools below the temperature of active oxidation. If possible, it is better to finish the welding process outside the parts being welded.

Vertical sutures are applied from bottom to top. The nozzle is positioned obliquely to the seam so that the argon jet is directed upward. The filler rod is located above the nozzle. If possible, protective screens should be provided to contain the argon gas at the welding site.

There is automatic welding with a non-consumable electrode. In this embodiment, the filler metal wire is fed into the welding zone automatically, and the arc between the tungsten electrode and the workpiece is ignited by applying a high voltage pulse.

MIG – semi-automatic argon arc welding with consumable electrode

Instead of a tungsten electrode, welding wire is fed through the torch.

In automatic mode, before igniting the welding arc, argon is supplied similar to the process with a non-consumable electrode. Next, voltage is applied to the wire, and the wire itself moves to the area where the seam begins. Contact occurs, the wire heats up, its end breaks off and is energized, and an arc is ignited. The arc length can be adjusted automatically or by self-regulation. Welding is carried out in similar modes.

At the end of the seam, the voltage supply gradually stops, the arc goes out, leaving no crater. After 10–15 seconds, the argon supply stops.

In semi-automatic mode, it is recommended to light the arc outside the welding zone on the auxiliary part, and then move the arc to the beginning of the seam. If this is not possible, first purge the torch with argon and then a live wire into the protected area.

In both cases, the argon arc process requires a room protected from drafts so that the gas protection of the molten metal is not compromised. 

To ensure the argon arc welding process, a certain set of welding equipment is required:

• This is a current source capable of supplying direct, alternating and pulsed voltage.
• Device for feeding welding wire.
• Burner with nozzle for supplying protective gas.
• Argon cylinder with gas reducer to reduce pressure.

Before starting the process, parts in the welding zone must be cleaned of dirt and, if possible, oxide films. Upon completion - from metal splashes. For this purpose, the equipment includes a metal brush.

Advantages and disadvantages of argon arc welding

The advantages include the ability to weld metals that lose their properties when the molten zone comes into contact with atmospheric oxygen. Stainless chromium-nickel steels lose their protective alloys in the weld area. Aluminum catches fire or becomes covered with a hard oxide film, making the seam impossible to make tight and durable. Similar problems arise when welding titanium, copper and other active metals and alloys.

Argon arc - has a relatively low heat release, the penetration zone is narrow, so the parts being welded do not warp.

With the correct selection of the welding mode, the molten metal does not splash, and the seam is neat.

Argon is cheaper than other inert gases, has a specific gravity greater than air, as a result of which it reliably protects the welding area when the seam is located at the bottom.

Flaws 

1. Among the disadvantages, the complexity of the process should be noted. Increased requirements for personnel qualifications.
2. The list of advantages mentioned the small width of the penetration zone. This is also a disadvantage that technologically complicates the process.
3. Specialized power sources capable of operating in pulse mode and supplying increased voltage to ignite the arc without contact between the electrode and the workpiece.
4. It is difficult or impossible to apply ceiling welds, since argon is heavier than air and sinks down, exposing the protected area. For high-quality ceiling joints, it is better to use more expensive helium.
5. Relatively high surface tension at the metal-gas interface, leading to stress concentration and the need in some cases to treat the seam after welding.

In general, argon arc welding produces a high-quality and durable connection.

Source: https://prompriem.ru/stati/argonovaya-svarka.html

Argon arc welding. Technology and equipment

Today, not a single construction site or production where it is necessary to connect metal parts can be done without such an operation as welding. This type of connection is considered one of the fastest and quite high-quality. There are several types of welding, but in this article we will talk specifically about argon arc welding. What is remarkable about it, its pros and cons, all this will be discussed below.

Technology

Argon arc welding is essentially the same as electric arc welding, but it uses an inert gas - argon, which is supplied to the place where the electric arc burns. Argon arc welding has two international designations: TIG (welding with non-consumable tungsten electrodes in an argon gas environment) and MIG/MAG (welding with an electrode wire in an argon or carbon dioxide environment).

Thus, a gas environment is created in which the metal melts. Due to the fact that argon does not interact with the metal, it does not change its chemical composition and this is a big plus. The fact that this gas is 1/3 heavier than air helps to displace the latter from the arc environment and isolate the molten metal from the effects of the atmosphere.

This protects the weld from the formation of an oxide film and generally improves the quality of the metal connection. There are cases when oxygen is added to argon in an amount of 4%.

This is due to the fact that when the edges of the metal burn inside a gaseous environment, argon does not completely protect the seam from various types of contaminants and moisture. And oxygen burns these harmful impurities, eliminating the formation of porosity in the seam.

But this is done mainly where very high quality welding joints are required. Usually one argon is sufficient.

Principle of operation

Equipment for argon welding consists of: a welding machine - which includes an inverter converter for generating an electric arc, an oscillator, a torch, an argon cylinder, gas hoses and welding cables.

Argon arc welding (tig) with a non-consumable electrode

Before starting work, the device is turned on and argon is supplied. To form an electric arc, the welder brings the tungsten (when welding with a non-consumable electrode) electrode a short distance to the workpiece. There is one important nuance at this stage. An arc cannot be formed when the electrode is directly connected to the workpiece, as with electric welding.

This is due to the fact that high ionization is required to create an arc in an argon environment. And since the tungsten electrode is refractory (melting point about 5000 °C) and practically does not burn, there is no formation of gases that promote ionization and ignition of the arc. Therefore, in such cases, an oscillator is used.

An oscillator is a device, usually installed in a TIG welding machine, that starts the electric arc in the case of a non-consumable electrode.

This happens as follows: by bringing a torch with a tungsten electrode a short distance to the part, the oscillator delivers a high-voltage, high-frequency pulse to the electrode, which electrically penetrates the distance to the part, forming ionization in a gaseous environment. Thanks to this, the arc is ignited and continues to burn.

When using direct current welding, a straight polarity connection is used. That is, “plus” is applied to the body of the product, and “minus” to the electrode. This is done because with such a connection, up to 70% of the heat is released on the part, that is, the “plus”, and only 30% on the electrode, the “minus”. As a result, the metal of the part melts, and the electrode is less susceptible to combustion.

The exception is aluminum welding. In this case, the best results are obtained by welding with alternating current, since this destroys the formation of the oxide film. As for the oscillator, when using alternating current, after ignition of the arc, it goes into stabilization mode, delivering breakdown pulses every time the polarity changes.

This ensures stable combustion of the electric arc.

Due to the fact that the tungsten electrode does not melt, to form a weld, a filler material is added to the place where the arc burns, which the welder holds with his left hand and, if necessary, applies.

Under the influence of temperature, a bath of molten metal is formed in the parts being joined. Since the burner has an inlet for connecting a gas hose, argon passes through a special cavity to the gas nozzle and escapes between it and the tungsten electrode. Thus, as if “enveloping” the electrode and the cooking bath.

In addition to the gas cavity, the burner also has inlet and outlet pipes for supplying cold liquid and removing heated liquid. This is necessary to cool the burner nozzle due to severe overheating.

TIG welding with consumable electrode

In this case, the role of the electrode is played by a metal rod coated with rutile. When the electrode directly touches the part, a short circuit occurs (as in conventional electric arc welding), as a result of which vapors of molten metal are formed, which give ionization in an argon gas environment.

The arc is ignited thanks to these vapors, so the use of an oscillator in this case is not necessary. The filler wire is fed manually or by a special automated mechanism, in the form of a drum with wire, rollers and an electric motor with a gearbox.

Typically this type of equipment is located at a specialized welding station.

Application area

Argon arc welding (tig and mig/mag) is successfully used when joining non-ferrous metals, alloy steels and aluminum. It is also good for welding aluminum and titanium alloys. For example, alloy wheels and other car components. If the thickness of the surfaces to be welded is small, argon welding can be carried out without additional additives.

Argon welding with a melting electrode is used to join stainless steel and aluminum.

Advantages of argon arc welding

The main advantages of argon arc welding are:

1) high quality of the resulting seam;

2) uniform penetration of the metal depth;

3) indispensable when welding products made of thin sheet aluminum;

4) wide scope of application, ranging from auto repair shops to aircraft manufacturing;

5) does not require frequent replacement of the electrode, which does not create defects when stopping and resuming work.

Disadvantages of argon welding

1) with manual welding - low productivity;

2) for high-quality welding, high qualifications and sufficient practice are required;

3) automatic option - not always convenient, as it is used for single-profile long seams. When welding short and differently oriented joints, it is not practical;

From what was discussed above, it is clear that this type of welding is much more effective and versatile than conventional electric arc welding. It is clear that for home purposes this can be an expensive pleasure, but when using this technology in business, the equipment will more than pay for itself in a minimum period of time.

Source: https://proinstrumentinfo.ru/argonodugovaya-svarka-tig/

What is argon welding, how is it performed and why?

Everyone is aware of the problems that arise when trying to weld metals such as copper, aluminum and some other non-ferrous metals. Standard manual arc welding with electrodes will not give a high-quality result. This is due primarily to the physicochemical properties of materials.

Experienced craftsmen know very well that there is simply no alternative to welding in a protective argon environment. You should become more familiar with the technology, since it is advisable to begin to become familiar with the welding process by studying key theoretical issues. It is the identification of positive and negative qualities that will give a more complete picture and will play a decisive role when choosing a welding mode.

• Basic information
• Equipment
• Technology
• Advantages and disadvantages

Basic information

Before considering the features of gas shielded welding, it is necessary to understand the principles of work. Argon welding has no fundamental difference from MMA welding. Often it is even called argon-arc. The metal is welded by partially melting and mixing a liquid substance with a molten additive. But in this case, this entire process is carried out in a gas cap consisting of argon. Why is argon chosen as a shielding gas?

1. Firstly, it is an inert gas, which means that it does not enter into chemical reactions.
2. Secondly, argon is heavier than air, so it settles in the weld formation zone.

The argon medium is obtained from a gas stream directed into the welding zone from a torch. The protective function of the gas is that it displaces atmospheric oxygen from the zone, preventing the formation of metal oxide. As a result, there is an improvement in the quality of the seam and an increase in the welding rate. If there were no protective gas, the resulting oxygen would lead to the appearance of pores and cracks in the weld area.

The scope of argon welding is very wide. You can weld products made of titanium; this metal is known for its inability to process.

Consumable electrodes, as well as non-consumable electrodes consisting of tungsten, can be used as consumables. Most often, tungsten wire is used to weld dissimilar metals.

Argon welding can be carried out manually, semi-automatically or automatically. The fundamental difference between the modes lies in the method of feeding the filler wire.

It is customary to divide argon-arc welding into three types, depending on the type of electrodes and the feeding method.

1. Manual welding is performed with a tungsten non-consumable electrode. This material was not chosen by chance, since tungsten has the highest melting point. This mode is usually denoted by the abbreviation RAD.
2. Automatic welding with a tungsten electrode is designated as AMA.
3. Consumable electrode welding is known as AAWP.

Now we are not talking about the advantage of one of the modes. Each master is inclined to choose one mode or another, based on technical conditions or his own preferences. According to the international classification, argon-arc welding is designated by the abbreviation TIG (from Tungsten Inert Gas). Even welding equipment is marked with this marking, which indicates that the inverter operates with argon.

Advantages and disadvantages

Argon gas welding is not a panacea. It, like any other process, has certain advantages and disadvantages. The question is that in some cases the shortcomings can be minimized or completely ignored.

The advantages include the absence of excessively high temperatures in the weld pool. As a result of this, the parts are not deformed. The use of argon provides a number of advantages.

1. Firstly, the gas is inert, so chemical reactions are completely excluded.
2. Secondly, argon is heavier than air, it sinks down, displacing atmospheric oxygen.

It is noteworthy that at a relatively low temperature the arc has sufficient thermal power, so argon welding is not only characterized by quality, but also by low time costs.

It was noted that the welder must have certain skills. However, these skills are not that difficult to acquire. Almost anyone can master this process.

Finally, a clear advantage of TIG welding is that it is possible to join metals that simply cannot be welded by other methods.

The disadvantages include the fact that welding cannot be carried out efficiently outside in strong winds. The wind will blow out the argon cap, and oxygen will enter the seam area. It should also be noted that there was a negative result among beginners. You have to overcome all mistakes yourself. It may take several attempts before the master learns to select the optimal welding mode.

Source: https://svarkoy.ru/teoriya/argonovaya-svarka.html