How to choose a welding machine for welding aluminum

How to choose an aluminum welding machine

Aluminum is a common structural metal. Craftsmen often repair parts at home, in garages, and small car service centers. The quality of seams depends not only on the qualifications of the welder and his experience, but also on the equipment. Manufacturers offer many models of different prices.

When purchasing an aluminum welding machine, it is important to consider some nuances. View not only the operating parameters of the generator, but also the regulators. The inscriptions on them should be large so that you do not have to wear glasses.

A good device is intuitive and designed for professionals of any skill level and age.

Features of aluminum welding

When choosing an aluminum welding machine for a workshop, the characteristics of aluminum alloys are taken into account. In production, when installing structures, devices for argon welding are used.

This is due to the properties of the metal: it melts at a low temperature - only 660°C, but a refractory film of oxides forms on the surface, which can be broken through by heating to 2200°C.

The degree of heating of aluminum is difficult to determine by eye - the metal does not change color, and it is more difficult for the welder to monitor the melt pool.

The ability of aluminum to actively oxidize negatively affects the quality of the weld. An argon atmosphere is used to protect the melt pool. A cloud of inert gas settles over the working area, preventing air access. To work with aluminum you need equipment to supply shielding gas.

When sealing cracks and minor repairs, it is effective to use argon TIG welding using a tungsten non-consumable electrode that supports the arc. The seam is formed with a surfacing wire.

In private properties, gardens, and garages, steel often needs to be repaired, so it is necessary to provide for the possibility of manual electric arc welding with conventional consumable electrodes (MMA).

Devices by welding method

Of the entire line of argon welding machines, the most reliable are considered to be inverters capable of converting alternating current with a frequency of 50 Hz into direct or high-frequency alternating current up to 50 kHz. Gas equipment is connected to models for TIG mode.

Source: https://svarkaprosto.ru/oborudovanie/apparat-dlya-svarki-alyuminiya

Aluminum welding machines: features of aluminum welding

Aluminum has its own special technical characteristics and cannot be welded using conventional equipment. The machine for welding aluminum with alternating and pulsed current protects the bath and hot metal from contact with air and quickly heats the work area. Fine settings allow you to select operating modes when the oxide film is destroyed and the aluminum does not start to burn.

Some features of aluminum and its alloys

Aluminum differs from other metals in its high thermal conductivity, chemical reactivity and low specific gravity. A welding machine for aluminum must work quickly and protect the weld pool well . Conventional equipment for metal structures and body welding will not be able to provide conditions suitable for welding aluminum.

Aluminum oxidizes quickly even when cold at room temperature. The oxide film formed on top is much harder than the base metal and melts at 2000⁰C, which is 2 times higher than the melting point of aluminum itself. Part of the strength of lightweight duralumin parts is provided by a hard film of aluminum oxide. When mechanically stripped to bare metal in the open air, the oxide film is restored very quickly.

Aluminum has a high coefficient of linear expansion when heated. If the parts are overheated, they will be severely warped.

High thermal conductivity contributes to the rapid spread of heat throughout the body of the part and the same almost instantaneous cooling of the seam, when the slag has not yet come out.

The process and its features

Based on the characteristics of the metal and its alloys, a welding machine for welding aluminum must have the following characteristics:

cracking the oxide film;
fine adjustment of modes;
work with pulsed and alternating currents;
inert shielding gas;
ability to work with aluminum and tungsten electrodes;
high current;
stable arc.

High temperatures are generated in the welding zone. It is necessary to cook aluminum quickly, without interruption . The duration of the burner operation is increased by water and air cooling of the holder and the body of the burner itself.

Cooling in the welding zone will occur more slowly if the parts are completely heated to a temperature of 250 - 280⁰C before work. This will eliminate the formation of a transition zone along the seam and hot cracks.

The difficulty in welding aluminum is the inability to clearly see the weld pool. The metal does not change its color when heated and melted.

What should a welding machine be like?

Welding of aluminum alloys is carried out using machines in TIG mode, alternating and pulsed current with a frequency of up to 200 Hz and a current of up to 200 A. These include:

semi-automatic;
argon-arc welding machines;
inverters.

An oscillator is used to break up the oxide film . It is installed in the device body and increases the oscillation frequency to 300Hz. Welding equipment operates on three-phase current 380V.

Before welding aluminum and high-alloy steel, including stainless steel, you should select refractory electrodes and appropriate additives. In both cases, a non-consumable electrode and filler wire with silicon and chromium are suitable.

Technology requirements

The technology begins with careful preparation of the ends to be welded . Before work, the welding area on aluminum and duralumin parts is thoroughly cleaned of oxides. A grinder with a fine-grained wheel is suitable for this. The suture is applied continuously in one pass. Welding of aluminum pipes is done in 2 passes, from bottom to top.

The gas is turned on before the arc ignites. The process begins at high currents. Welding is completed at low currents. Welding machines must change current and voltage after starting work.

To weld aluminum, a tungsten consumable and non-consumable electrode is used . Filler rods for aluminum are used in two types: pure metal and cast aluminum with the addition of silicon.

Welding thin aluminum with argon. Thick sheets and parts are boiled in a protective argon-helium gas.

Before starting welding, the electrode should be sharpened . Melting into a semicircle. The non-consumable one is sharpened at an angle of 40⁰ with a small platform. During the welding process, there should be a drop of pure metal at the end that is smaller than the diameter of the electrode.

[stetxbox id='alert'] Important! If the drop on the electrode darkens, it means there is not enough gas or the argon is not pure, with the addition of air. If an increase in gas consumption does not change the situation, you need to change the gas cylinder.[/stextbox]

The arc length when welding aluminum should be constant within 12 - 15 mm. A shorter one will burn through the sheet, especially thin ones. A long arc will not heat up the metal as it should.

Welding of duralumin is carried out using the same technology as pure metal . Only the current decreases. When choosing the best way to weld duralumin, you should choose aluminum wire. On pulse devices, it simply flows in a stream into a heated bath and connects with the metal.

If a hobbyist has a boat and needs to repair it, a pulse inverter with an oscillator and a tungsten electrode with aluminum filler wire will do. A cheaper option for rare applications is AC argon-arc welding. For workshops with a large volume of work, it is better to choose a high-performance pulse machine or semi-automatic machine.

Installation regulators

Aluminum requires fine adjustments and lowering the current during the welding process. The main functions that an aluminum welding machine should have:

contactless ignition;
zoolocation – adjusting the arc polarity ratio;
AC balance adjustment.

Non-contact ignition ensures the ignition of the arc without striking the part and its constant burning.

When operating in AC mode, the polarity of the arc changes from direct to reverse and vice versa. Zoolocation allows you to select the optimal direction of the current and the frequency of polarity changes.

The duration of pauses and pulses is adjusted by a balancer depending on the thickness of the metal being welded.

Additionally, the welder sets:

starting current;
magnitude and nature of the main current;
Arc forcing.

In addition to these functions, several timers ensure high-quality welding. They are responsible for:

gas supply before welding;
current decay time;
supply of gas after completion of work.

shielding gas is supplied before the start of the welding process - ignition of the arc. This ensures that the bath is completely closed before the melting process begins.

You need to start welding aluminum at a high current, then lower it. The timer automatically reduces the current after a certain time after starting operation.

Aluminum cools quickly, but it still takes time to prevent the seam from oxidizing and cracking. After the electric arc is turned off, gas is supplied to the working area for another 5–7 seconds .

Installation and shutdown

Regardless of what material needs to be welded, the equipment must be turned on and off in a certain sequence.

Check the integrity of the housing, cables and grounding.
Connect the cables to the device and parts.
Place and secure the gas hose on the holder.
Connect cooling.
Set operating modes depending on the thickness of the metal and the length of the seam.

A duralumin sheet is placed on the slab and secured. After this, you can turn on the equipment. If the current is constant, then you should choose reverse polarity and special electrodes operating in AC/DC mode. They are convenient for welding materials that cannot be processed using standard methods.

After welding, you should wait a short time until the part cools down, without turning off the argon. Then turn off everything in reverse order.

Operation of equipment during operation

Aluminum is welded at high currents and high frequencies. For equipment, this mode poses a large load. The work-rest regime specified in the technical data sheet of the equipment should be observed.

You should fine-tune the device and check the grounding.

When working on a semi-automatic machine with aluminum wire, the length of the hoses should not exceed 3 meters. The nozzle should be chosen wider than usual. Aluminum wire is soft and expands greatly when heated. As a result, friction occurs and it jams.

The gas nozzle is selected with a wide nozzle and a mesh inside. The flow is uniform and covers the bath well.

Kinds

For aluminum, alternating current electric arc machining is mainly used . A hot plasma stream can easily melt any metal, but aluminum has a refractory film and will warp greatly when heated by a gas burner. In addition, it actively reacts not only with oxygen, but with nitrogen and carbon. The result is a brittle seam with a thick layer of slag and parts with a large lead.

Semi-automatic

Semi-automatic welding machines use aluminum wire . It is fed into the burner at a constant speed and melts in the bath. Attached to the handle is a nozzle that supplies protective gas. The whole process is controlled by a semi-automatic machine; the welder’s hand only directs the molten pool to form a seam.

Semi-automatic welding is highly productive. It is good to use in production with a large number of parts for welding from different steels and metals. When working with aluminum, a continuous seam up to 5 m long can be applied.

Inverter equipment

For welding aluminum and its alloys, a conventional inverter with a cylinder containing argon gas connected to it is suitable. Argon, helium and their mixture are used as protective flux.

Most often, home welding work, from which aluminum and duralumin are welded, is carried out using simple inverters . The device produces a current sufficient for short-term welding of non-ferrous metals.

For welding, special electrodes are selected that are designed to work with metals with high thermal conductivity, these are the O3P and O3A series, diameter 2.5 - 3 mm. They are a rod made of a special alloy and coating.

Before welding aluminum with an inverter , the electrodes must be well calcined. If moisture remains in their coating, used as a flux , it forms pores in the weld metal and slag inclusions.

The seam should be applied slowly, ensuring that the bath has time to warm up and the slag to float to the surface. The inverter connection of parts gives a strong and beautiful seam with a small heating zone on the sides.

Argon welding

Manual argon arc welding is most often used by amateurs when repairing a car or boat, or welding small parts . Non-consumable tungsten electrodes and filler wire are mainly used as consumables. Together with them, argon, a shielding gas, is supplied to the welding zone.

Non-consumable electrodes create high temperatures using an arc. At the same time, the coating also does not burn; there is no flux that is usual for manual welding.

In addition to tungsten, carbon electrodes and special ones for welding metals with a high heat transfer coefficient, such as aluminum, copper and their alloys, can be used. They are designated A3. Available with rutile, cellulose and tungsten coating.

Argon welding can be performed on inverters and transformers. The main condition is the gas connection.

Consistency at home

At home, you should first check that the equipment is working properly. Then the details are prepared. They are installed on a special workbench or plate. Fixed for welding, if possible without tacks.

Immediately before work, clean it, removing the oxide film mechanically.

Electrodes and wire must be dry, calcined in an oven. If possible, parts are also heated in a furnace or with an argon burner. After this, welding is performed.

Aluminum can be welded with long seams horizontally. Short lines are used for vertical lines and ceilings.

Electric arc welding of aluminum in an argon environment can be performed in a garage or home workshop. It is best to use the inverter as a universal equipment.

Source: https://svarka.guru/oborudovanie/vidy-apparatov/dlya-alyuminiya.html

Welding machine for aluminum: how to choose the right characteristics (current strength, class, functions)

Aluminum is increasingly used in the production of everything. It is used to make dishes, containers, and even spaceships. Therefore, craftsmen who understand welding aluminum parts are highly valued.

But the result of working with this material depends not only on the hands of the welder. The equipment he used has something to do with it. For aluminum, argon arc TIG welding is classically used.

This technique works great on any aluminum elements, such as sheets or small parts. It is based on the use of the inert gas argon together with welding equipment with a TIG function.

This article will help you understand which aluminum welding machine will make your job easier.

general information

Nowadays, the best equipment option for welding aluminum or stainless steel is considered to be a small semi-automatic device, which must have built-in parameters for TIG welding.

"Resanta", "BlueWeld", as well as other manufacturers well-known among welders, definitely have such a semi-automatic machine on their shelves.

So even in small towns it is not difficult to find a machine for argon arc welding of aluminum.

Making a choice

In addition to the main TIG function, an aluminum welding machine must have other additional characteristics. The main thing is that it should be understandable on an intuitive level for everyone: from a young beginner to an experienced master.

All levers, toggle switches, connectors, buttons should have the name in large font so that even a person with imperfect vision can easily handle the device.

The welding arc generated by the semi-automatic machine must be non-contact and have a slow decay function. It’s good if you have the ability to change the polarity settings, use the current pulse welding mode.

These features will make work not only more enjoyable, but also faster.

Many models of welding devices have been created for processing stainless steel and aluminum. In order not to get lost among this diversity, you need to understand what nuances can become the main ones when choosing.

Current strength

The main characteristics of the equipment are related to current. You need to look at what maximum current the semiautomatic device can support. The size of the parts you can weld, the density of the metal, and welding capabilities depend on this.

Professional models of aluminum welding machines can easily handle a current of two hundred amperes. In the case of one device, this may not be enough, but the other will distribute the current so that this force will be sufficient.

For example, two devices may have the same amperage, but their price will be different, as a result of the work itself.

For example, BlueWeld PRESTIGE TIG 222 has a price of about two thousand dollars, and Svarog PRO TIG 200 P DSP is only five hundred. Both in the passport have the same current strength - 200 A.

And it seems that it makes no sense to pay more for the first one, because its maximum current is the same as the second one. But in practice everything is more complicated.

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Manufacturers set prices for a reason anymore. Expensive machines for welding aluminum, as a rule, produce a completely different result. A cheap device will do the job, but the quality of the seams will be “C”, while a more expensive device will do the job “A+”.

The point is what components were used in production, and what additional functions are “attached” to the device. BlueWeld is more expensive not only because of its fame.

To assemble it, they simply selected expensive equipment, and added modern technologies during development. This may explain the price of many foreign welding devices.

Class

Our example shows that the prices of aluminum welding machines divide them into classes. Welding equipment can be household, semi-professional, professional and industrial.

We are not going to talk about the latter, since this is not our topic. But let's look at the first three in more detail.

For home, garage, and country house repairs of aluminum products, devices in the range of $500-700 are suitable. They cope well with rare car repairs, assembling small items (like a gate), and other household problems.

If you need a device for such work, then these small semi-automatic machines with a small number of built-in parts will suit you. In addition, they are easy to repair and improve.

Half-pro options are more expensive, ranging from $1,000 to $1,300. They have more functions than household ones. This gives the master more room for improvisation.

They also weigh more due to the fact that they have more filling in the form of additional microcircuits or circuit boards. This equipment is suitable for welders working for themselves (on-site design work), as well as for small workshops.

Professional aluminum welding equipment can cost well over a thousand dollars. It all depends on how much the manufacturer values its products, and what markup the seller allows himself.

This equipment is large-sized, but at the same time it is designed to perform complex connections of even the thickest sheets of metal. There is no point in buying such a device for home repairs, since many of its functions will not even be used.

Multifunctionality

Devices that are suitable for aluminum often have not only a TIG function, but also an MMA mode. That is, you do not have to use only argon welding.

You can also weld with coated electrode rods using manual or semi-automatic arc welding. Such machines for welding aluminum are universal.

But this does not apply to absolutely all models, so check the equipment passport to see if it has both options. “Double” ones are more expensive than simple ones, but for the sake of functionality it’s better not to skimp.

Dimensions

Rectifier and transformer welding machines take up a lot of space. The same cannot be said about inverters. For this reason, the latter took the lead, replacing both of the first options.

Devices for TIG welding of aluminum are much more functional than their predecessors, but they will not weigh as much as a soldering iron. There is no way a large number of parts will fit into a super compact shell.

If a TIG device weighs ten kilograms or less, it means that the manufacturer has reduced the number of its functions for the sake of compactness. If there are still a lot of functions, then the price of the device will become higher.

Equipment even for household work usually weighs 20 kilograms or more. You need to pay attention to this, given that in addition to the device itself, you need to “carry along” additive materials, gas cylinders and other accessories.

Source: https://prosvarku.info/apparaty/apparat-dlya-svarki-alyuminiya

Choosing a argon arc welding machine - 5 main principles

There are dozens, if not hundreds of argon arc welding machines on the market. The possibility of TIG welding is implemented in many modern models of manual arc welding inverters and in semi-automatic machines. The variety of options creates certain difficulties in choosing the right model, especially for a beginner.

To get started, you should answer 5 simple questions:

What types of metals will you be working with?
What is the thickness of the parts being welded?
Is it useful to weld structures less than 1 mm thick or made of stainless steel?
How intensively do you plan to use the device?
Do you have experience in TIG welding or are you just starting out?

The answers will determine the functionality that must be present in welding equipment in order for it to flawlessly cope with the assigned tasks. There are important differences between AC and DC devices. Direct current is required while welding various types of steel, copper, cast iron, etc. For materials such as aluminum, magnesium and metals with an oxide film on the surface, machines operating on alternating current must be used.

D.C Alternating current

Various types of steels	Aluminum
Stainless steel	Magnesium alloys
Cast iron
Copper
Titanium alloys

There are also universal options. Their functionality determines the required type of current to be used for welding a specific type of metal. It's easy to distinguish them. The name of such devices often uses the abbreviation AC/DC (for example, FUBAG INTIG 200 AC/DC).

ANSWER #2. Welding current range

TIG welding of metal structures of a certain thickness is available in the appropriate welding current range. Let’s say the main scope of work is steel metal structures up to 6 mm thick. An inverter with a current of up to 200 A is suitable here. Welding aluminum 6 mm thick will require more than 200 A.

Well, a device with a range from 5 to 200 A will allow you to work with stainless steel up to 1 mm thick and aluminum up to 5 mm. Here we provide general recommendations for the INTIG series welding machines and for the most commonly used metals and thicknesses. This will help you navigate when choosing equipment for your tasks.

Type of metal Metal thickness, mm Type of current Current strength¸ A

Steel alloys	1,0	DC	20 — 40
1,5	DC	40 — 70
4,0	DC	120 — 140
Aluminum	1-2	A.C.	20 — 60
4-6	A.C.	120 — 180
6-10	A.C.	220 — 230
11-15	A.C.	280 — 360

When choosing a device, pay attention to the stability of the arc at a current strength of less than 10 amperes. The parameter determines the ease of arc formation and the level of control. It is important to know that the starting current should be much lower than the operating current. This is especially critical for welding thin sheets of metal. .

If you have to weld metals of small thickness, then you should pay attention to argon arc welding machines operating in pulse mode. The pulse mode facilitates welding at low currents. During the welding cycle, the welding current changes from maximum (pulse current) to minimum (pause current) with a certain frequency. The process is stable, heat input is reduced - metal warping is minimized, the part does not overheat.

This mode is necessary to control the heat input into the weld or welding without a filler rod. At the same time, welding can be carried out using both direct and alternating current.

The operating time of the welding machine (work cycle) directly depends on such characteristics as the duration of switching on. The higher its indicator, the longer the tig installation is used without interruption. For example, consider the operating cycle of the FUBAG INTIG 200 DC device. It will work for 6 minutes at a maximum welding current of 200A and will need 4 minutes for a technological break. In practice, it is extremely rare for anyone to cook without stopping for longer than 3-4 minutes, because... Periodically you need to stop to prepare the area for welding, adjust parts, change the welding rod, etc. By correctly assessing the expected load, you can save a lot. An underestimated value of this parameter will lead to an increase in the time required to complete welding operations, since welding will have to be interrupted frequently to cool the inverter. Unreasonably high switching times for tasks significantly increase the cost of equipment. All TIG welding machines are equipped with high-frequency ignition and crater filling functions.

Crater filling. From the point of view of the quality of the welded joint, it is necessary to exclude the formation of a crater in the final part of the weld. For this purpose, the tig device provides a smooth current reduction mode.

High frequency ignition. Provides a confident start to the welding process - the arc ignites without contact with the metal surface, which eliminates metal burning. In addition, no tungsten inclusions remain on the metal.

And some more useful stuff

1. Gas purging. This function protects the seam from oxidation.

2. Liquid cooling of the torch. Intensive use of the device implies overheating of the burner. To prevent this from happening, the models are equipped with a cooling system, which is also worth considering when choosing a TIG installation.

3. Supply voltage. Devices with high welding currents are usually produced in a three-phase version. Their younger brothers are single-phase.

Now you have everything you need to make the right choice. If you have any additional questions or want to visually consolidate your knowledge, check out our video tutorial on the FUBAG RUSSIA channel:

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Source: https://fubag.ru/tips/vybor-apparata-argonodugovoy-svarki-5-glavnykh-printsipov/

Choosing a reliable machine for welding aluminum, advice on selection and work

Even experienced welders, when faced with joining aluminum using the manual arc method for the first time, are often disappointed with the quality of the weld. If you need to regularly work with such a “capricious” metal, then our article will help you choose a welding machine for aluminum that will be able to create high-quality sealed seams.

In this article: [Hide]

Which machine is best for welding aluminum Using MIG/MAG machines for welding aluminum
Using TIG machines for aluminum welding
selection of aluminum welding

Selecting a welding machine

In addition to the TIG function, pay attention to some additional features. In particular, a good device should be intuitive for a master of any age and level of training. All adjustments, buttons and connectors must be labeled in large letters so that even an elderly person with poor eyesight does not have difficulty operating the device.

The device must generate a welding arc in a non-contact manner; in addition, it must have a slow arc extinction function. It would be useful to have the ability to control the polarity balance and the pulse welding mode. All these functions will not only simplify your work, but also significantly speed it up.

There are a lot of models of devices designed for aluminum and stainless steel on sale. The assortment is really large, so before purchasing, decide on some nuances that may become critical.

Welding current strength

The first thing you need to pay attention to is the maximum welding current. The thickness of the metal that you can weld and your capabilities as a craftsman depend on it. Most more or less serious models have a welding current of 200 Amps.

And you may think that this is not enough. But it’s not so much the number that is important, but how the device manages this characteristic. For comparison, you can take two machines with the same welding current strength, but radically different costs and results of work.

For example, the BlueWeld PRESTIGE TIG 222 device costs more than $2000 and produces 200 Amps, while the Svarog PRO TIG 200 P DSP costs $500 and produces the same 200 Amps. A beginner will probably think that it is not worth paying extra for the expensive model from BlueWeld, since it produces the same maximum current. It’s only when you use it that the fun begins.

Devices with the same current strength, but from different price categories, produce radically different results. A cheaper device does the job, but is not able to provide the same quality of seams as a device from a high price category.

It's all about the components used to design the devices and the additional functionality. The model from BlueWeld is more expensive not only because it is a well-known brand.

It’s just that the manufacturer uses higher quality components when assembling it and introduces new technologies. And so it is with many devices.

Device class

Based on our example above, it is not difficult to guess that devices are divided into classes. Main classes: household, semi-professional, professional and industrial. We will not talk about industrial ones, since they are not entirely relevant to the topic of our article. But we’ll talk about the other classes in more detail.

Household welding machines for aluminum cost up to $500-700 and are readily purchased by home craftsmen. Such devices are suitable for infrequent repairs (including car bodies), for assembling small metal structures (for example, a canopy) and other simple work. This is the best option if you need a device for your country house or garage. Such devices weigh little because they consist of a small number of components. Easy to repair and modify.

Semi-professional models cost up to $1000-1200 and differ from household ones in greater functionality, thanks to which the welder has more opportunities. The weight of such devices is greater than that of household models. Again, due to increased functionality and the appearance of additional details. A semi-professional device is suitable for a master with an individual entrepreneur engaged in field work, or for a small workshop.

Professional machines cost from $1,200 to infinity (depending on the impudence of the manufacturer and seller :)) Such units are capable of performing the most complex welding tasks and are used in large industries or at expensive service stations. It is not advisable to buy such a device for home use, since in such conditions it is difficult to reveal its full potential.

Versatility of the device

Many units for aluminum and stainless steel are equipped not only with a TIG function, but also with an MMA function. This means that you can cook not only using argon, but also using regular coated electrodes. Simply put, it is simple manual arc welding.

This feature turns the device into a universal assistant. However, not all models are equipped with this feature. When choosing a machine, pay attention to whether it is equipped with TIG and MMA welding.

These aluminum welders are a little more expensive, but the versatility is still worth paying for.

Dimensions of the device

Welding inverters themselves are quite compact compared to transformers or rectifiers, which were actively used in the 20th century. However, a TIG welding machine comes with a lot of features that cannot be packed into an ultra-compact body. Don't expect a functional aluminum welding machine to weigh 5 kg like budget inverters for manual arc welding.

If a TIG welding machine weighs up to 10 kg, then it either has limited functionality due to its size, or is very, very expensive. Devices for household welding with more or less acceptable functionality weigh from 20 kg and more. Take this into account, because in addition to the inverter, you also need a gas cylinder and welding components, and all this must be transported somehow.

To solve this problem, you can buy or assemble a special cart. But the cart will not help if you need to take the device to the dacha on a crowded train and take it back to the apartment when cold weather sets in. So pay attention to the weight and dimensions of the device when purchasing.

Types of welding for working with aluminum

Differences in the properties of aluminum and other metals have led to the emergence of a number of features when creating permanent structures. Aluminum parts can be connected using one of three types of welding:

The most common of the methods listed above was and remains TIG or manual arc welding. It is used for joining products made of aluminum and alloys based on it for critical purposes. Despite the fact that the welding speed with this method is 4 times lower than with the other two, this cannot be called a disadvantage. The proof is the result, namely a high-quality and neat welding seam, and an almost complete absence of pores.

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Source: https://instanko.ru/osnastka/apparat-dlya-svarki-alyuminiya.html

Choosing a welding inverter for aluminum welding

Without light and durable aluminum alloys it is no longer possible to imagine human economic activity. These materials are also used in everyday life, they break down and often need repair.

Therefore, the topic of welding aluminum at home with an inverter, which is quite widespread among skilled people, is very relevant.

The aluminum welding process has its own characteristics, which are important to take into account in the work, and our task is to consider in detail the specifics of this process and the necessary equipment and devices. We will try to study this topic comprehensively and carefully.

Aluminum welding process and its features

Connecting aluminum parts requires taking into account the physical and chemical properties of this light and durable metal. The fact is that a thin and durable oxide layer with a melting point of about 2,000 o C is formed on its surface, and the melting point of the alloy itself is about 650 o C.

It is almost impossible to mechanically remove the oxidized layer, so the welding process takes place in argon, a neutral gas that prevents access of aggressive oxygen to the connecting seam.

Aluminum welding is carried out at home with an inverter, which has an operating mode with alternating pulse current, which also helps to destroy the refractory oxide film.

Welding inverter for aluminum and stainless steel

The industry produces various aluminum alloys, which differ in strength properties, weight and processing conditions. Based on weldability, the most common aluminum alloys are divided into the following main groups:

silumin, aluminum-silicon alloy (Al2, Al4 and Al9), which has limited weldability;
aluminum-manganese alloy AMts, weldable without restrictions;
aluminum-magnesium alloy, AMg3, is weldable without restrictions, AMg1, AMg5 and AMg6 are weldable to a limited extent;
duralumin, aluminum-copper compound grades D1, D16 belong to the difficult-to-weld group;
heat-sealable alloys of the AB, AK, B95 grades are also difficult to weld.

In most cases, high-strength welding is carried out with alternating current using argon and a non-consumable electrode; it provides high-quality connections of metal of different thicknesses. But it is also possible to weld aluminum with an inverter using direct current of reverse polarity on the electrode.

In this case, it is necessary to warm up the elements to be welded, thoroughly remove the oxide layer and use calcined, special electrodes for coated aluminum. Several passes must be made along the seam, and the parts themselves, with a thickness of more than 5 mm, must first be prepared for the process.

Sometimes a welding machine for durable welding of aluminum is equipped with an oscillator, which allows you to connect workpieces made of stainless steel, titanium and perform delicate welding of metals of different thicknesses.

You need to know that different welding methods and equipment have their own advantages and disadvantages, which must be taken into account when purchasing a specific machine.

Types of aluminum welding

The presence of alloying additives in aluminum alloys, as well as the oxide layer, do not allow the metal to be welded using conventional methods, so special methods of joining parts are used for this work. The most popular of them are the following methods:

connecting parts with a tungsten non-consumable electrode in an inert environment using alternating current (AC TIG);
welding in an argon environment with direct current with semi-automatic wire feed (DC MIG);
fusion using a welding inverter without the use of inert gas with coated consumable electrodes (MMA).

The argon arc method (AC TIG) is used for careful welding without pores and rough seams with manual wire feeding and argon supply of 6-8 liters per minute.

Alternating current ensures the melting of the refractory oxide layer on the surface of the aluminum plates and creates a weld pool necessary for the process of joining parts.

This aluminum welding machine allows you to repair thin-walled parts made of various alloys, but is very sensitive to contamination of the tungsten non-consumable electrode.

When welding DC MIG, an adjustable wire feed to the joint of parts and an argon supply from a gas cylinder with a flow rate of 7-9 liters per minute are used. The work is carried out using direct current using a special torch with a nozzle. An adjustable gearbox is used to supply gas, and the welding wire is pushed by a special mechanism in the body of the welding machine. Welding requires sufficient qualifications and, with experience, gives good results.

Welding using the MMA method requires increased attention to the cleanliness of the surfaces being welded, since the process occurs without inert gas. Some effort must be made to minimize the influence of the oxide layer.

To clean the surface, use a mechanical method, as well as acetone-containing solvents. Before starting work, the parts to be welded are heated to a temperature of 250 °C, and the electrodes for aluminum are calcined because they have a hygroscopic coating.

With this method, reverse voltage is applied to the electrode.

Welding sequence at home

The industry offers a variety of welding machines for welding ferrous, stainless steel, titanium and aluminum. When choosing a unit, you must be guided by the type of welding work that you need to perform, as well as the cost of the product. If there are difficulties, you need to consult with specialists who will help you make the right choice and suggest how to quickly and easily improve your welder’s qualifications.

Welding aluminum with an inverter at home

A universal inverter for aluminum welding must provide the use of alternating, direct and pulsating current, and have the greatest possible degree of adjustment of output parameters. Different types of welding require their own components and additional equipment. Welding also requires training and skills, and we will tell you about the basic requirements when working at home, namely:

thorough mechanical cleaning of the welded surfaces from the oxide layer is required;
it is necessary to degrease the surface with acetone;
for successful operation, parts with a thickness of more than 5 mm must be prepared by chamfering at an angle of 45 degrees;
when arc welding without argon, it is necessary to calcinate the electrodes and heat the workpieces to a temperature of 200 degrees;
the use of high-quality electrodes, wire and argon will ensure a strong weld;
smaller parts and a thin, strong seam can be obtained using argon arc welding with alternating current, or using a semi-automatic device with direct current;
before work, it is necessary to check the strength of the connections in the inert gas and coolant supply system;
check for reliable grounding connection.

Let's sum it up

We have described the general principles of working at home when welding aluminum using an inverter. It should be taken into account that work of such complexity requires high-quality equipment, components and qualifications. Professionals will help you make the right choice and undergo initial training, and mastery will appear over time.

Source: https://electrod.biz/apparat/vid-svarki/svarochnyiy-invertor.html

Aspects of selecting a machine for aluminum welding

Creating durable and reliable structures from various metals and alloys requires special equipment. Moreover, each material has its own samples of welding machines, which significantly complicates their selection. And while standard equipment can be used for steel products, the properties of aluminum require the use of only special techniques.

This material is lightweight and has high thermal conductivity. Therefore, to work with it you will need an aluminum welding unit. At the same time, the process itself is considered one of the most complex, which requires its implementation by a specialist.

Welding machine design

Complete set for argon welding

Structurally, such equipment consists of the following components and mechanisms:

Gas cylinder and hose;
Cassettes with wire, mechanism and pipeline for its supply;
Burners;
Batteries;
Control unit.

The operation of the device for welding aluminum is as follows: gas enters the arc and thereby protects the product from oxidation. To supply it, a semi-automatic welding torch is used. They are equipped with a handle made of insulating material.

Welding unit design

It contains:

The torch package includes a nozzle and a tip for supplying current. The ceramic materials used in its manufacture are designed to protect the nozzle from sticking of molten metal.

Elements made of copper-graphite alloys are used as tips. They allow you to ensure high-quality contact. The torch is connected to the welding machine in one of two possible ways: a connector or a solid connection.

The functions of the power source in the device can be assigned to a transformer or inverter. Not only the dimensions, but also its price depend on which of the listed devices is used.

Welding inverters are most widely used, as they are lightweight and easy to transport and operate.

Wire feeding in a semi-automatic welding machine for welding aluminum is carried out in various ways:

Pushing;
Pulling;
Combined.

The first one is considered the most common. It is carried out using a drive located in the body of the device. The combined method usually uses both pulling and pushing mechanisms. Moreover, they are used for long sleeve lengths.

The wire used in welding machines can be:

Steel;
Made of stainless steel;
Aluminum.

Operating principle of the equipment

The connection of parts made of non-ferrous metals or alloys is carried out using a semi-automatic welding machine for aluminum. When carrying out work, you must act in a certain sequence. First, you should set the polarity of the welding current, usually for flux-cored wire it is direct, and for a gas environment it is reverse.

Let's watch the video, a little about the principle of welding:

Then a reel of wire is mounted and carbon dioxide is connected. To do this, a reducer is installed on the cylinder, which is connected to the device using a hose. Before starting welding, adjust the wire tension.

Criterias of choice

Before purchasing such complex equipment, you need to determine the scope of work that you decide to perform with its help. For professional use you will need one model, and for home use another. Moreover, they must meet the requirements placed on them and operate with the least amount of energy and other consumables.

If you find it difficult to choose, then perhaps you should entrust the purchase of a welding machine for welding aluminum to a professional. This will eliminate problems during operation.

The best models of devices for working with aluminum

If you believe the opinion of consumers, the champion in its class is the powerful programmable TIG welding machine from the Tiger brand. It's lightweight, feature-packed, and features high-performance electronics to deliver incredible power in a small package.

Equipment of this brand is suitable for mechanized and even robotic production, and is available in 170 and 210 A versions. The DC model has a source for welding with direct current, and AC/DC also has an alternating current.

The inverters of the Invertig PRO series have proven themselves well. Devices of this class are easy to use, reliable, easy to operate, and combine advanced welding technologies. They are highly energy efficient, have maximum operating time, and air or water cooling of the burner.

Almost all the energy they consume is converted into a welding arc. Such devices are an ideal choice for mechanized or automatic production.

Welding inverters for argon-arc welding of the Mitech brand (AC/DC) are used in combination with non-consumable tungsten electrodes. They are suitable for permanently connecting parts made of steel and non-ferrous metals, including aluminum. The basis of the unit is a high-frequency transformer with a ferrite core. But the main feature of the device is the use of power transistors from the world's leading manufacturers Toshiba and Fuji (Japan).

Conclusion

Before you start welding parts, you should carefully study the instructions for use. This will help to avoid errors in work and will allow you to achieve high quality and reliability of the seam.

Source: http://GeneratorVolt.ru/invertornyjj/aspekty-podbora-apparata-dlya-svarki-alyuminiya.html

Aluminum welding machines: review of models, prices, settings and all the nuances

Due to its chemical and physical properties, welding of aluminum structures is carried out differently than welding of steel, stainless steel and other metals. To ensure that the seams are strong and even, and the aluminum alloy construction is reliable, special technologies .

Aluminum alloys are characterized by strength, low weight and high resistance to corrosion. The combination of such qualities made it possible to use them in many industries: aircraft manufacturing, shipbuilding, the automotive industry and others.

Aluminum in its pure form, without impurities, has very little strength and its application is of a slightly different nature. It is rarely used in the manufacture of structures, only in the food and electrical production cycles, where it is used for the manufacture of molds and packaging.

Welding aluminum is complicated by its low melting point , so during work there is a high probability of burning through the workpieces.

Chemically active aluminum has a peculiarity - in air it is covered with an oxide film, which serves as protection from environmental influences. The same film is an obstacle to good welding of parts made of aluminum and its alloys.

The fact that molten aluminum does not change its color complicates the work process - it is more difficult for the welder to visually control the width of the seam. A high level of worker training and specialized equipment are required.

We invite you to familiarize yourself with a very detailed material about TIG welding of aluminum

Welding unit regulators

The devices have many settings that help you maintain the necessary parameters. Among them:

Initial gas supply relay, it will help set the gas purging time interval.
Starting current regulator.
Regulator of the main current, setting its magnitude and character.
The decay time of the current is controlled by a timer. Unscrew the regulator to the zero position.
Arc forcing regulator. With its help, the working element is ignited easily and quickly.
Pulse frequency switch for welding with pulsed current.
Pulse mode balancer that sets the duration of pauses and pulses.
Regulator of the ratio of forward and reverse polarity of the arc during the AC welding process.
Timer for gas supply at the end of the welding process.

Operation of welding equipment when working with aluminum

The operating procedure is as follows:

Select AC mode. We set the required current and balance.
We turn on the device and cooling system.
On the gas cylinder reducer we set the desired gas flow rate.
We begin work by pressing the button on the burner.

Be sure to check all connections , connect grounding and make sure there are no gas leaks. Each operation must be performed carefully, in compliance with all rules. Work is carried out wearing a protective mask and a special suit.

Equipment and materials for argon arc welding

The quality of an arc welding seam depends on the polarity of the current and its type, as well as on the diameter of the electrode, welding speed and arc voltage.

The depth of the seam increases with higher current, and the width is directly related to the speed of work - at high speed you will get a narrower seam. Large diameter electrodes reduce the depth of metal penetration.

Below are the characteristics of some devices, the use of which facilitates the process of welding aluminum structures.

Semi-automatic MIG welding of aluminum

MIG welding involves feeding the welding wire during operation and protecting the welding area with argon supplied through the torch. Aluminum, with its high thermal conductivity, requires constant monitoring of arc power to prevent burnout. The welder also needs to ensure proper wire feeding, which will be needed more when working with aluminum and its alloys than when working with other metals such as steel or stainless steel.

about such welding is presented below

Features of semi-automatic MIG welding of aluminum:

A prerequisite when welding aluminum using a semi-automatic MIG is the use of pulses. They penetrate the oxide film, destroy it, and prevent the aluminum from overheating. Only pure argon is used, without impurities of foreign gases.
Torches for working with aluminum wire should be short in length. The diameter of the wire is selected especially carefully - for thin wires it becomes problematic to carry out uniform feeding, and wire with a large cross-section requires a more powerful current.
The rollers for feeding aluminum welding wire must have a U-shaped cross-section, and the cable channel cannot be used metal. For aluminum welding wire, a graphite or Teflon channel is used.

With any welding method and equipment, the quality of work will largely depend on the preliminary preparation of the metal - chemical and mechanical cleaning are required. Do not neglect this if you want to get a reliable and durable weld seam.

When choosing a device, everyone is guided not only by the convenience and functionality of the equipment, but also by the financial component. Many craftsmen even prefer homemade devices. This option is justified only if you know well the principle of operation of the device and are confident in your abilities.

It is safer to purchase a high-quality industrial-made device. The price range of the devices and installations offered is large, it is always possible to choose the most acceptable option. Remember - a reliable device and strict adherence to the operating instructions are the key to your safety.

Source: https://generatorexperts.ru/invertornye/apparaty-dlya-svarki-alyuminiya.html

Which welding machine for welding aluminum and duralumin should a beginner choose?

The process of welding aluminum and duralumin has several features that must be taken into account both when working and when selecting equipment for it. Firstly, aluminum is a rather capricious material, therefore, doing aluminum welding yourself requires sufficient experience in this matter.

As for the tool, the welding machine for welding aluminum must be an inverter one. Also, the aluminum tig welding machine must have dimensions convenient for transportation in a car and have handles for carrying. It is advisable that the machine comes with an oscillator for aluminum welding.

In general, any inverter semi-automatic machine can perform such work as aluminum and duralumin welding. Therefore, for a beginner, the further choice of equipment should be based on the features of aluminum welding described below.

Beware of complications

You can see the video below about how aluminum welding occurs. We focus your attention on the main difficulties that arise when welding aluminum. The first problem encountered when tig welding semi-automatic aluminum is the formation of an oxide film. Aluminum has a melting point much lower than the oxide layer, so pulse welding is needed to break through the film and melt the aluminum.

Aluminum and duralumin welding occur with the possibility of burning through the part being welded, since aluminum has high thermal conductivity. Therefore, it should be warmed up well before starting welding work.

And:

Cleaning an aluminum part is a prerequisite for carrying out a procedure such as welding aluminum; the video with welding instructions, which you will find in our article, begins with this procedure. This will break up the resulting film to some extent and then speed up the work. But! You need to start welding no later than 24 hours from the time of stripping.
It is very important that the aluminum welding machine maintains a constant arc length during the process. Its length for working with aluminum should be in the range of 12-15 mm, otherwise problems may arise. With a shorter arc length, a burn will form, with a longer arc, non-fusion will occur. The exact value of this parameter depends on the thickness and alloy composition of the material.
Since aluminum has high thermal conductivity, it is subject to rapid cooling and, as a result, hardening. Therefore, certain difficulties may arise in filling the crater at the completion of the weld. Therefore, novice welders to work with aluminum will need a welding machine with a function that gives a higher current to heat the part at the beginning of work, and a low current at the end to fill the crater. An oscillator for welding aluminum will not be superfluous.

In general, for such a skill as welding aluminum, as for any other, practice is necessary. With it will come not only a complete understanding of the process itself, but also an understanding that the wide range of modern welding machines available must be understood in order to perform the job efficiently.

After practicing for some time on available materials, you will definitely be able to master the technique of welding aluminum and develop an understanding of the equipment issue.

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Source: https://swarka-rezka.ru/kakoy-svarochnyy-apparat-dlya-svarki-al/

How to choose a welding machine for aluminum

Aluminum welding may be necessary to seal a crack in the engine oil pan or gearbox. This is often how a damaged engine cooling jacket block is repaired this way. Aluminum welding machines are in demand in the chemical and food industries, in the manufacture of containers, collectors, filters and other products.

But aluminum and its alloys AlMn, AlSi, AlMg are less weldable due to the main feature - the presence of a refractory oxide layer on the surface. Its melting point is 2044 degrees, while the metal underneath it flows after 660 degrees.

This is a major problem because the low current is unable to melt the outer layer and the filler metal is deposited on the surface. High current strength leads to through burns.

Therefore, classical technologies are not suitable for aluminum welding.

Other difficulties in working with this metal include the following:

Small difference between melting and freezing temperatures. Aluminum becomes fluid at 660 degrees. But if you let it cool by only 15-20º C, then it already begins to crystallize. An aluminum welding machine is required that can maintain the operating current in such a range that a seam can be formed.
Increased thermal conductivity. Heat spreads through aluminum 5 times faster than mild steel. The weld pool cools quickly, and the part can become significantly warped over a large area even from a small seam.
Preservation of color in molten form. When welding ferrous metals, it is easy for the welder to control the condition of the weld pool and the amount of additive supplied, since it becomes dazzling white, in contrast to red slag. Aluminum does not change color in liquid form and it is more difficult for the welder to visually understand how well the seam is formed.
Increased shrinkage. After cooling, the deposited beads of metal can sag significantly, which forms pits in the weld and requires repeated surfacing from above.
Interaction with the external environment. Upon contact with ambient air, aluminum evaporates hydrogen, which leads to large pores in the weld structure. Such a connection will not withstand the pressure of water or other liquid. It is necessary to protect the weld pool from external gases.
Increased fluidity. In the molten state, aluminum is similar to water - it is more difficult to direct the liquid metal with a torch, especially when making a weld in an inclined plane. This also leads to accelerated through-burns.

The first welds of novice aluminum welders are always bad. Gradually, the problem is solved by training in practice. But the correct choice of a welding machine designed for joining aluminum is of paramount importance here.

Which machine is best for welding aluminum?

Since covered electrodes with an aluminum core are commercially available, it seems that the cheapest way to weld this metal is manual arc welding using an inverter. But in reality, MMA welding on aluminum will only allow you to connect the two sides of the metal with drops of additive applied on top.

A strong and airtight seam will not work here. For a quality connection, you will need a welding machine for welding aluminum with MIG or TIG modes. Each of them has its own characteristics, which should be taken into account when choosing.

Using MIG/MAG machines for aluminum welding

MIG welding is the use of semi-automatic machines in which the welding wire is continuously fed through a channel directly into the torch. The second cable with a clamp is attached directly to the product. The short circuit of the wire against the surface of the workpiece leads to the initiation of an electric arc. At the same time, the gas from the nozzle isolates the weld pool from the external environment.

pros

high welding speed;
good visibility of what is happening in the weld pool;
The welder's second hand is free to support the workpiece or stay at height;
you can create continuous long seams;
after the end of the process there is no slag crust.

Minuses

Expensiveness of the equipment itself. There are also additional costs for shielding gas (a mixture of argon and carbon dioxide).
Aluminum filler wire is thin and flexible, so it “walks” a lot and is more difficult for the welder to guide.
If you often need to alternate between welding ferrous metals and aluminum with one semi-automatic machine, then changing the steel channel in the torch to a Teflon one takes a lot of time.
The seam from a semi-automatic machine on aluminum is not uniform in width. If it is located on the front side of the workpiece, then subsequent mechanical cleaning is required.

What functions should semi-automatic machines for aluminum have?

Aluminum cannot be joined using any semi-automatic machine. Welding equipment must have the following functions:

Hot Start. This function is called “Hot Start” because it allows you to apply a high-quality seam from the first millimeters of the connection. To do this, a high idle speed (80-90 V) is maintained on the wire, and the current is initially supplied slightly higher than the main one.

For aluminum, this is useful by quickly heating the surface and destroying the oxide. Thanks to this effect, the seam begins to form immediately, without the additive beads sticking on top. On professional devices, you can adjust the “Hot Start” adjustment value to determine how “hot” it will be.

Pulse. This function does not produce an even base current, but promotes its alternation. The result is an amplitude where the current increases until the working pulse, and then pauses with a decrease. At the moment of peak stress, the oxide melts, and during the pause period, smooth fusion of the filler metal is ensured with a minimum amount of spatter.

On professional semi-automatic machines, you can adjust both the pulse frequency and its length, which allows you to customize welding depending on the thickness of the aluminum and the type of its alloy. The function is especially relevant for thin metal to avoid overheating of the surface and the formation of through holes.

Dable Pulse. Doubles the previous effect. In addition to the amplitude alternating the base and main currents, there is an oscillatory rise and fall of the peak current. This function further improves the quality of aluminum welding down to droplet transfer of metal. Minimal heat input prevents the workpiece from overheating and deforming it. The seams are thin but deep, and the welding speed increases.

Using TIG machines for aluminum welding

TIG welding of aluminum is carried out using an inverter that produces alternating current.

In one hand the welder holds a torch with a tungsten electrode. Its contact with the surface of the part to which the mass is connected leads to the formation of an electric arc. Tungsten does not melt, so the length of the electrode does not change. For welding aluminum, a round shape of sharpening the rod is used.

In the welder's second hand, the filler wire is fed into the weld pool to increase the height of the seam and make the joint stronger. Argon shielding gas escapes from the burner, preventing contact with outside air.

Pros of TIG for aluminum welding

the seam is tight and airtight;
no mechanical processing required;
there are no pores in the structure;
You can make narrow seams 2-3 mm wide.

Cons of TIG for aluminum welding

increased consumption of funds for filler wire and gas;
low welding speed;
high cost of equipment;
Only short seams can be created;
the needle quickly becomes covered with splashes and its shape needs to be adjusted;
When welding aluminum sheets 1-2 mm thick, a substrate is required to prevent failure of the heated metal.

The quality of seams that can be obtained when welding aluminum using TIG welding.

What features should TIG inverters for aluminum have?

Although any inverter can be equipped with a valve torch for TIG welding, it is possible to qualitatively join aluminum using the argon arc method only if you have the following functions:

Pulse. Plays the same role as in a semi-automatic machine. Reduces heat input and prevents fluid-flowing material from burning out. Professional devices support setting the pulse wave. The square wave gives deep penetration and high process speed.

Triangular allows you to easily weld thin sheets of aluminum with minimal heat transfer. The rounded wave makes it easier to control the weld pool for uniform penetration of critical joints.

The sinusoidal one produces a soft arc with a wide coverage of the weld pool, but not deep penetration.

Pre and post gas. Starts a 2 second pre-purge of shielding gas to displace ambient air from the welding start point. Argon is supplied after the arc is interrupted for 3-10 seconds, allowing the weld pool to crystallize normally without oxygen interference.

Switch to AC. TIG welding with an inverter can only be carried out using alternating current. To do this, the characteristics of the device must include the designation AC/DC.

MIX TIG. This mode alternates the effect of direct and alternating current on the material. First, AC comes into operation, destroying the oxide film with its frequency. Then it is replaced by DC, which provides deep penetration with uniform distribution of filler metal. This function is especially practical when it is necessary to connect aluminum with a thickness of 2 and 7 mm to each other.

Balance adjustment. Allows you to set the frequency of automatic change of voltage polarity, which, with a positive value, extends the service life of the tungsten electrode and increases the penetration depth, and with a negative value, it reduces heat input and protects against burn-throughs and deformations.

Having studied the requirements for aluminum welding machines, you can easily select welding equipment for your auto repair shop, workshop or garage.

selection of aluminum welding

Source: https://srbu.ru/instrumenty-i-oborudovanie/1704-svarochnye-apparaty-dlya-alyuminiya.html