Welding work for beginners instructions for use. Learning how to cook with inverter welding

Welding sheets of thin metal with an inverter allows you to quickly and efficiently produce a metal product.

Thin-sheet material is called a material with a thickness of up to 5 mm, it is often used in the production of blanks for cars, motor boats, as well as for the manufacture of pipes, various hull structures, etc.

The main problem in welding thin sheets metal is more likely to be damaged.

The reason for this may be the careless movement of the welder, as a result of which a burn may form on the workpiece.

In addition, welding of thin metal, carried out by a person without experience, may turn out to be of poor quality due to non-compliance with the technology.

Since the welding process is carried out exclusively by the inverter using low current, even a slight gap in the working distance between the workpiece and the electrode must not be allowed.

Otherwise, an arc break cannot be avoided. Therefore, it is not recommended to start welding thin sheets with an inverter without knowledge of the process features.

Welding thin metal requires, like any other welding process, to have on hand protective clothing: a special welding helmet, gloves and outer clothing made of rough fabric, but under no circumstances should rubber gloves be worn.

Step one

We carry out the setting of the welding current and select an electrical conductor that will allow you to work with an inverter.

We take the welding current indicator based on the characteristics of the metal sheets being joined.

Usually, the manufacturer indicates the current strength for specific cases on the inverter case.

We use electrodes for inverter arc welding with a diameter of 2-5 mm. Next, we insert an electrical conductor into the holder, connect the ground terminal to the workpiece.

To avoid sticking, do not bring it to the part too sharply.

step two

Welding of thin metal using an inverter apparatus begins with the ignition of the arc.

We touch the line to be welded at a small angle with the electrode a couple of times, which will activate it.

We hold the electrical conductor at a distance from the workpiece to be welded, which will correspond to its diameter.

Step Three

If all of the above is done correctly, a high-quality seam connection should be obtained.

On the this moment there is scale or scale on the surface of the weld, they must be removed with an object, such as a hammer.

The following video for beginner welders will demonstrate how to properly connect thin sheets of metal with an inverter.

How to control the arc gap?

The arc gap is the distance formed during welding between the elements to be joined and the electrode.

Be sure to maintain a stable size of the specified distance during the operation of the inverter.

If you cook thin metal with an inverter and at the same time keep a small arc gap, then the welded seam joint will be convex for the reason that the main part of the metal does not warm up well.

If you cook thin metal with an inverter semiautomatic device and at the same time keep too much distance between the electrical conductor and the workpiece, then such a large gap can interfere with penetration.

The electric arc will bounce, the weld metal will lie crooked.

The correct and stable distance will make it possible to obtain a high-quality seam connection, while it is necessary to weld thin metal with an inverter, as mentioned above, with a gap corresponding to the diameter of the electrode.

Having gained experience and the ability to control the inverter arc length, it will be possible to achieve optimal results.

Due to the electric arc, which is fed through the gap and melts the base metal, a weld pool is formed. It also moves the molten metal into the weld pool.

Features of the formation of the weld

If during the welding process the movement of the electrode is too intense, then all that can be achieved is a deformed joint.

This fact is explained by the fact that the line of the weld pool is below the level of the base metal, and if the penetration of the arc into the base metal is strong and fast, it pushes the pool back, as a result, a seam appears.

That is why it is necessary to control that the welding seam line is located on the surface of the metal sheets.

A high-quality seam can be achieved by circular and zigzag movements of the electrode along the surface to be joined.

With zigzag actions, it is necessary to monitor the formation of the seam line alternately in three positions: from one edge, from above the weld pool, from the second edge.

Here, one should not forget that the weld pool moves with heat, which is very important when changing the working direction.

With a lack of electrode metal, an undercut is formed - a narrow groove in the base metal along or along the edges of the weld, appears as a result of a lack of metal to fill the bath during transverse movement.

In order to avoid the formation of such a lateral recess or undercut, it is recommended to monitor the outer boundaries and the weld pool, if necessary, adjust the groove width.

Operate the weld pool allows the force of the electric arc located on the tip of the conductor.

Do not forget that when working with a welding product at an angle, the bath will not stretch, but will push.

Therefore, a vertically located electrical conductor allows you to get less convex welding joints.

The process is explained by the fact that at this time, all thermal energy, the weld pool is pushed to the bottom, melted and distributed around.

With a slightly inclined position of the product, all the force is repelled back, as a result, the weld pops up.

If the electrode product is tilted too much, the force is transferred in the direction of the seam line, which does not allow effective control of the bath.

To achieve a flat seam connection, apply the slopes of the electrical conductor at various angles.

In this case, welding should begin at an angle of 450, which will make it possible to control the bath and correctly connect the metal with a semi-automatic device.

Welding of thin sheet metal with a consumable electrode

In order for the process of welding thin metal with a semiautomatic device to be successful, it is necessary to use an electrical conductor with a suitable diameter.

For example, for sheets of thin metal with a thickness of up to 1.5 mm, products with a diameter of 1.6 mm should be used.

Correctly welding thin metal with a consumable electrode means preventing overheating during the welding process, which can lead to burning in the product.

The electrical conductor is moved along the line to be welded at an average speed, as soon as there is a risk of combustion, the speed is increased.

The current strength during inverter welding of metal sheets should not exceed 40 amperes.

When choosing the current strength for working with a consumable electrode, it is better to make a test weld, which will simplify the solution of the task.

At the same time, on a test product, you can cook semi-automatically in different modes taking into account the speed of movement of the electrode.

It is necessary to cook in such a way that it is possible to fully ensure the penetration of the steel edges and at the same time not burn through the material.

A feature of welding thin metal with a consumable electrode inverter is the instantaneous melting of the edges, which does not allow you to fully monitor the weld pool.

That is why it is better to start semi-automatically cooking thin sheets of material after gaining experience.

In the process of welding thin sheet metal products, spot or intermittent welding technology can be used.

Due to the short functioning of the arc, tacks are formed, subsequently the electric arc is extinguished, then the process is repeated at a distance equal to the size of 2 or 3 electrode diameters.

The period between the creation of points is best minimized so that the molten metal does not have time to cool.

This method is ideal if you need to weld leaky structures made of thin sheets with an inverter. Spot grips will eliminate possible risk warpage of metal.

How to choose the polarity when working with an inverter?

Polarity is the basis of a good welded joint. Direct polarity provides for reduced heat input to the base metal with a narrow but deep melting area.

With reverse polarity, there is a reduced flow of thermal energy into the material with a wide and shallow melting area of ​​the base metal.

It is the polarity of the electrons that must be paid attention to before starting work with the inverter.

If you cook metal at direct current, then you can use the positive and negative charge of the source.

But at the same time, you need to know where to connect which charge.

Here it is necessary to take into account that if a material being welded is provided with a positive charge, it will become very hot.

If this charge is connected to an electrical conductor, then the electrode will get very hot and burn, which can lead to burning of the metal.

The way out is the reverse polarity of the inverter and the optimal current strength.

In the process of working with an inverter, the electrode is connected "+" to the inverter arc, and "-" to the sheet of metal.

A few of the following tips and thematic video material will also be useful for novice welders:

• The ability to observe the weld and control it from all sides in the process of arc welding with an inverter will allow you to get a high-quality result and eliminate the formation of burnt holes;
• During welding, the electrical conductor must be kept as close as possible to the product until a red spot begins to appear. This will mean that there is already a metal drop under it, due to which the metal sheets are connected;
• When moving the electrodes slowly metal surface, appearing red-hot drops of metal connect the segments of the sheets and thereby form a welding seam.

After studying the above information and watching the videos, it will be much easier to weld thin sheets of metal with an inverter.

Welding inverters (with their low price of 7-10 thousand) form high-quality seams, even if they are in the hands of beginners. Of course, the work will turn out good if you follow simple rules. All of them are described in the article. However, before work, beginners need to read the instructions for the device. There are usually several useful tips as well as safety precautions. Remember that everyone can learn to weld metal.

How a welding inverter works

Welding inverter - a tool for welding metal. It got its name from the fact that it converts alternating current into direct current. And although the inverter efficiency is about 90%, its power consumption is low, so you don’t have to worry about high electricity bills.

Most often, the welding inverter runs on 220 volts, some types - from 380. At the same time, it is possible to work at reduced voltage: a 3 mm electrode, for example, can be used at 170 volts.

It is much easier to weld with an inverter, compared to a transformer or rectifier. In addition, even a beginner can hold the arc. That is why most people learn the art of welding on it.

Preparation for work

What electrodes to use

The electrode is a rod made of metal, which is coated with a special coating - a slag mixture. Gas-forming substances are sometimes added to it. Coating will protect the molten metal from oxidation.

The rod is selected depending on the type of metal to be welded. For example, to work with carbon or stainless steel, you will need the UONII electrode grade. There are also universal electrodes. These include the ANO brand. They are used for reverse and forward current of any polarity.

The electrodes are also divided by diameter, which varies from 1.6 mm to 5 mm. The size is selected depending on the thickness of the metal being welded: the larger it is, the larger the diameter. A table may come in handy when working with a welding machine.

The thicker the rod, the more power the inverter welding machine must have. Therefore, for beginners, a diameter of no more than 4 mm is suitable; thin metal can be welded with an electrode and in 2 mm.

Polarity and value of welding current

The thickness to which the metal can be melted directly depends on the set current strength. The arc power is also determined by this indicator. The size of the electrode determines the required current strength.

Depending on the surface, the value of the welding current is selected. On horizontal surfaces it is maximum, on vertical surfaces it is less by about 15%, on overhanging surfaces it is 20%.

A household type welding machine can deliver up to 200 amperes. On a professional instrument, the values ​​\u200b\u200breach up to 250 and above. The direction in which the current flows will determine the polarity. On the inverter, it is possible to change the polarity.

As you know, the current moves from minus to plus. Therefore, the "+" terminal heats up more. This feature allows for high-quality metal welding. In the event that the parts to be welded are thick, then the positive terminal is connected to one of the parts. This method is called direct polarity.

A negative terminal is attached to thin products. This connection method is called reverse polarity.

Welding instruction

Welding basics

Before proceeding directly to welding metal products, you need to study the main design features of the inverter welding machine. They are shown in the diagram.

The inverter itself has average weight: up to 7-8 kg. At quality tool on the side of the metal case there is a ventilation grill that prevents the transformer from overheating.

There is an on/off button on the back panel. On the front there are two connectors: "+" and "-". A cable is connected to them, at one end of which there is an electrode, and at the other - a clamp. The cables themselves must be of sufficient length and flexible.

Step by step instructions on how to cook with an inverter.

1. Inverter welding begins with the preparation of protective equipment. At your disposal is a welding mask, a thick jacket, rough but not rubber gloves.
2. Select an electrode. If you are a beginner, then do not use a rod thicker than 4 mm. On the front panel, adjust the desired amperage. Wait a little; If you bring the electrode directly to the metal, sticking will occur.
3. We fasten the clamp (it is also called the mass terminal) to the metal surface.
4. The arc is ignited. Then we bring the electrode to the metal and touch it a couple of times. Thus, the rod is, as it were, “activated”. The distance at which the electrode is held is usually equal to its diameter.
5. The rod during welding can move according to such schemes.

Arc ignition at the beginning of welding + (Video)

Striking the arc is the first step, and beginners have problems with it. First, the rod is tapped a little on the metal so that the grease is removed from it. Then a method similar to lighting a match is applied. The electrode is led over the surface of the product and slightly touches it. If suddenly the rod sticks to the metal, it is either sharply removed from the side, or the inverter is completely turned off.

You need to strike until a bright arc appears. To prevent the arc from disappearing, keep the electrode at a distance of 4 mm from the metal.

How to move the electrode during welding + (Video)

The electrode can only move along certain trajectories. They have already been shown. If you move the electrode only straight, the seam will come out discontinuous. The speed of its movement affects the properties of the seam. If you move quickly, the seam will be narrow and not convex, if slowly - wide and convex. In the place where the seam will end, the electrode is delayed for 3-4 seconds.

How to form a weld and avoid defects + (Video)

An uneven seam, most often, is formed when the electrode moves too fast. Speaking about creating an even and high-quality seam, you need to introduce the concept of a weld pool. The weld pool is that part of the metal that is in liquid state. Filler material enters this part. The appearance of a pool is a good sign that the welding is proceeding correctly.

The contour of the bath is located under the surface of the metal part. The bath forms a good seam if the welding arc passes evenly and to a great depth into the workpiece. It is necessary to ensure that the seam does not go down, but remains at the level of the surface. good connection easier to create if done with an electrode circular motions. In this case, the bath should be distributed in a circle.

When seaming corners, remember that the tub moves with heat. Adjust the force of the arc to control the dimensions of the tubs.

The seam will not be too convex if you keep the electrode close to the vertical position. If you tilt the rod (for example, by 45˚), then the seam will begin to emerge. And when the electrode is very close to the horizontal position, the bath begins to diverge, and the seam is bent. Therefore, the optimal tilt angles are from 45˚ to 90˚.

Arc gap control

The arc gap is the distance between the metal surface and the electrode. The gap at each stage must be the same so that the welding is of high quality and without defects.

If the gap is small, then the weld will turn out to be too convex, and the material itself will not fuse well. This happens because the product cannot heat up. With a large gap, the welding arc will move from side to side, and the seam will come out crooked and fragile. The correct gap shown in the figure will give good penetration and a smooth seam.

How to weld thin metal sheets + (Video)

For welding thin metal, it is preferable to use the reverse connection of the inverter, i.e. "-" is attached to the sheet. In this case, the current strength should be at medium values. It is better to choose an electrode that will have a long melting time. The MT-2 model is well suited. It is used by welders long time and therefore performed well.

The rod, in the case of thin metal, can be tilted by about 35˚. First, you carefully bring it closer to the metal, then wait for a red spot to appear, turning into a drop. Smoothly move the electrode so that the drop remains the same size. So the seam will be even.

To understand how to learn, you must first find out what exactly these devices are. The welding inverter has a fairly compact design, it is much easier to move it from one place to another compared to an ordinary transformer-based welding machine. In addition, working with a modern device is much more convenient.

Weld metal elements with the help of an inverter, it is quite reliable only if you know at least its approximate device. First of all, the design of this equipment does not take up too much space: all the necessary parts are placed in a small metal box, which does not exceed half a meter in length, usually no more than 20 cm in width, and about 30 cm in height. The total weight of the structure is about 10 kg.

Its principle of operation is to issue electric current with suitable strength and tension. The inverter produces a direct current in the area of ​​the welded surface, which is formed from the alternating voltage located in the household network - 220 V.

The devices always have two terminals - the cathode, or negatively charged conductor, and the anode - positive. One of them is used to connect the electrode, and the other is connected to the metal that will be welded. After the voltage begins to be applied, a single electrical circuit is formed. If you make a slight gap in it, the size of which will be only a few millimeters (as a rule, no more than 8), then air ionization occurs in this place and a corresponding electric arc occurs.

To be correct, it should be understood that the bulk of the heat is released precisely in electric arc, which burns at a temperature of about 7000 degrees. This allows you to qualitatively melt the edges of the welded metal blanks.

When the arc sparks, not only the edges of the metal melt, but also the electrode itself, as a result, all these materials mix with each other. If welding work is carried out poorly, then slag, which, as a rule, is much less dense than the metal, will remain in the thickness of the metal. This significantly reduces the quality of the resulting welded joint.

Typically, slag comes to the surface and prevents the elements to be welded from being oxidized by oxygen contained in the air, or from beginning to absorb nitrogen from the environment. After the molten metal begins to solidify, a welded joint is formed.

The main parameters of welding work

To learn from the experience of experienced welders, you need to understand such a thing as current polarity, because it can be direct and reverse. The first is formed if the current flows from the cathode to the anode. Reverse polarity is obtained in the opposite situation.

If a person knows how to cook correctly, then he will understand that the highest temperature will be formed at the terminal from which an electric current begins to flow. When using straight polarity, the temperature will be higher directly on the workpieces. As a rule, welders who are just starting to learn the basics of this craft use this technology.

With reverse polarity, a higher temperature is formed at the electrode. This technology is useful when working with sheets of metal of small thickness, as well as when working with metals that do not respond well to overheating, which can lead to damage to the workpiece.

An important role is played by the thickness of the electrode or welded wire. This indicator directly depends on how thick the parts to be welded will be. In principle, this indicator should be repelled when choosing the current strength. It turns out that the higher the thickness of the electrode, the greater the strength of the electric current must be applied to it.

It should also be borne in mind that the current strength indicator is directly affected by the location of the seam - horizontal, vertical, ceiling, and so on. For the gradual development of inverter welding, you should carefully study the table, which shows the corresponding current strengths, electrode diameters and other important indicators related to welding.

What are the main positive qualities of the inverter?

The inverter apparatus is much more convenient for carrying out welding work. Even most professional welders say that this technology is much better and simpler than a primitive transformer. Thanks to the application this product you can not only easily form an arc, but also get it ultimately as stable as possible.

This effect helps to prevent excessively strong spatter of the metal. The inverter is also good because it provides a number of different kind additional features. In particular, one of the most useful functions is the so-called "Hot start", which allows you to make the welding current at the very beginning of the work as strong as possible. This makes it much easier and faster to form an arc.

Another feature is "Strong Arc". This element is activated only if the electrode is too close to the elements to be welded. With such a development of events, the device will increase the current in automatic mode. This allows the metal to be melted as quickly as possible so that the electrode does not stick to the workpieces.

The third useful quality is the Anti-Zalip option. If necessary, it makes the electric current as low as possible so that the electrode can be torn off the metal surface very quickly and work can continue. The function is very useful for those who have not yet fully figured out how to properly tear off the electrode from the workpiece.

The inverter is a fairly economical device. If we consider electrodes with a diameter of 3 mm, then for their high-quality use it is quite enough to set a voltage with a power of 4 kW - this fully corresponds to the normal parallel connection of two electric kettles.

The cost-effectiveness of the design in terms of electric current consumption allows literally within one season to justify the rather high cost of an inverter welding machine.

What safety precautions must be observed?

To figure out how to cook with inverter welding, you first need to understand the basic safety standards. The fact is that welding work is particularly dangerous for human health and life, so they should be approached with caution.

• Before starting work, you need to clean the adjacent space from wooden objects and other things that can quickly ignite. This moment is very important for those people who are just starting to master welding. Electrodes, slag, molten metal are very hot, which can cause a quick fire.
• You should wear tight clothing that covers your entire body if possible: long tight trousers, a jacket or sweater with long sleeves. This is done so that drops of molten metal cannot get on the skin and cause severe thermal burns.
• Eyes and face must be protected with a special mask with built-in dark glass or light filter. It will not let in sunlight, but the burning of the arc will be perfectly visible, and this filter will also allow you to carefully consider how the metal is melted and the weld is filled.
• If the arc burns, but metal welding does not occur, then this may indicate a malfunction of the apparatus or insufficient current. You can add it on the working panel of the equipment. If this does not help, then the tool should be immediately de-energized, since some kind of breakdown must have occurred inside it. It may cause electric shock.
• It is strictly forbidden to work in wet weather, when too low temperatures and other adverse atmospheric phenomena, because this also often causes electric shock.
• You should not observe the conduct or performance of welding work without a protective glass - this causes a severe burn of the cornea, from which you will have to recover within a few days. Burns of this plan are different: a weak degree is characterized by the appearance of bright spots before the eyes; the middle degree begins with a feeling of sand in the eyes; severe can cause partial or complete loss of vision.

How to light an arc correctly?

People seeking to figure out how to learn how to weld with an inverter welder should first practice how to properly strike the arc and keep it burning throughout the entire period of work.

At the first stage, you should connect the terminals, depending on what polarity you plan to work with - direct or reverse. If there is no experience in welding at the moment, then only direct connection should be used. It is better for a beginner welder to take universal electrodes suitable for most metals: their diameter is 3 mm.

The use of thicker electrodes is undesirable, as they can cause serious arc fluctuation and unstable arc burning. Working with such consumables requires better skills.

Initially, you need to set the current to 100 A. Using the mask out of habit can cause some discomfort, but it can be sacrificed to preserve vision. Before direct ignition of the arc, you need to lightly tap the electrode on the metal to knock the coating off its edge.

You can set fire to the arc in one of the following ways:

• strike;
• light touch.

If you take into account all the points considered, then figuring out how to cook with a welding inverter will not be too difficult. Moreover, it can be used for various materials.

If you do not know how to learn how to cook with a welding inverter, video and prepared step-by-step instruction will help you understand all the nuances of this process. It is not uncommon for novice welders to pick up a machine to weld a car body, patch holes in metal structures, etc.

You can learn how to cook a car body or other parts for beginner welders using an inverter. Correctly using a welding inverter is not as difficult as many people think. Even if you have never picked up this tool, and are poorly versed in the types of electrodes, this will not become an obstacle on the way to self-repair car or the manufacture of some kind of metal structure.

There are a lot of reasons to learn how to cook with an inverter. Having at your disposal Svaris 160, Svaris 200 or any other good device, to master the welding business will be even easier. Not the last role is played by the apparatus used in the welding process.

The whole process is divided into three main stages:

• Training;
• Inverter arc ignition;
• Making a weld.

Training

The inverter is a welding device. This device provides the connection of metal elements by welding them together. So you can properly weld the body of your own car, close up holes in a metal fence, fix window bars and perform a number of other household tasks.

Preparation consists of several steps.

1. Place of welding by the inverter. Determine in advance the space where your Svaris 160 or 200 will be located for welding activities. To do this, you need to clear the area of ​​debris, wooden, paper objects that can catch fire due to a flying spark. It is best to cook by placing the inverter on a concrete floor.
2. Inverter connection. Usually, to connect a household inverter, they use single-phase circuit. This allows you to work with an inverter from a 220V outlet. The whiskers of the inverter have plus and minus terminals. The electrode goes to the minus, and the plus is connected to one of the treated surfaces.
3. Worker protection. An important point that directly affects your safety. Is it possible to work without gloves? In no case. You can cook only if you have a complete set protective equipment- gloves, mask, tight suit, rubber boots. The body must be completely closed.
4. Turn on the inverter. Take in your hand the terminal on which the electrode is installed. A special toggle switch turns on the device and you can start the ignition process. Pre-set the desired value of the welding current. If the electrode for the inverter has a diameter of 3 mm, the current will be 100 A. It will be correct to pre-examine technical documentation, which was equipped with your Svaris 160, 200 device or another inverter model. It is extremely important for beginners to understand how to cook the same car body. But it is better to get the first experience on simpler surfaces. Try just welding a couple of metal blanks together.

arc inverter

The next stage is the ignition of the inverter arc. Here, follow a few recommendations so that the device does what you expect from it.

• Learning how to ignite an inverter is not difficult, but it will take time. At first, you may encounter certain difficulties, but soon it will take a minimum of effort;
• For all novice welders, the main difficulty begins precisely with the ignition of the arc. Therefore, it is not right to think that only you are doing so badly;
• To ignite the arc of the inverter during the first welding on cold metal, a strike is used. This method is similar to lighting a match on a box;
• Pass the electrode over the workpiece, slightly touch the surface of the part you are going to weld;
• The first time you may encounter sticking, that is, the electrode will simply stick to the metal. To correct the situation, simply tilt the terminal to the other side. So you break the rod. If it does not work, just disconnect the inverter from the power supply;
• You need to strike until the arc appears. In no case do not start striking without lowering the mask over your face. Looking at the arc without filters is detrimental to vision;
• To maintain the arc, you need to fix the electrode tip at a distance of 3-5 millimeters from the surface to be welded;
• Here, for beginner welders, another difficulty arises - holding the desired distance. If you get too close, the electrode will stick. When removed, the arc is lost, so you will have to re-ignite;
• During welding, the electrode will gradually be consumed, and the coating will burn out. The metal will begin to fill the space in which the welding process is performed. Therefore, do not forget to gradually move the electrode along the seam with your hand.

Weld

In addition to the weld, you need to understand the essence of the weld pool. This is the only way to achieve the desired result.

1. When the arc is ignited, a puddle of molten metal forms. It is called a welded bath.
2. To connect the parts, weld the car body, the electrode should be gradually moved along the boundaries of the two elements to be welded.
3. A pool will move behind the electrode, which is called the liquid metal zone.
4. To achieve the desired quality of the connection of parts, the welder must oscillate the electrode relative to the seam being created.
5. If you lose the arc when you start welding, you don't have to worry about having to re-ignite. Now it is easier to do. To do this, bring the end of the electrode a few millimeters closer to the surface.
6. Special masks are good because you can see a bright arc and a weld pool through them. The direct contact of the electrode with the surface is less visible, but you cannot remove the mask with light filters for this.
7. When the length of the rod remains literally 5-6 cm, welding should be stopped. Turn off the inverter with the toggle switch, change the electrode, after which you can turn on Svaris 160 or 200 again.
8. After completing the welding operation, restoring the car body, be sure to tap the seam with a hammer. So you remove the formed slag from the surface. You can determine the cleaned surface by its appearance. The seam devoid of slag shines.

Electrode movement

Many beginners who start brewing for the first time mistakenly think that Swaris 160 or 200 will do all the work for them. We do not argue, Svaris 160 and Svaris 200 are really good inverters. But having a quality device is not enough to do the job right.

The main mistake is rectilinear movements when creating a seam. Professionals don't cook like that. In order to repair the car body or perform a number of other operations, you need to learn how to use the device correctly and observe the seam.

1. Having prepared the car body for welding, and turning on your Svaris 160 or Svaris 200, you need to gradually move along the intended seam line.
2. At the same time, the movements are zigzag, spiral, Christmas tree - that is, a return trajectory is used. In this way, the desired quality of melting is achieved, and the risk of gap formation is minimized.
3. The formed welded surface depends on the speed of movement - the thickness of the weld, width, depth, etc.
4. When completing the line, linger on the last point for a few seconds. This will make the seam complete, will not allow the formation of craters - depressions. Only after that change the electrode.

Welding is one of the rather complex, but highly demanded technologies for working with metals. Wherever you look, welded joints are necessarily used. Without this process, no one can do industrial production, construction company, repair or service company. Welding becomes indispensable in the construction and improvement of one's own home.

But here's the problem - welding requires a certain degree of preparedness. You can, of course, if necessary, contact the master welders for ads, or to your friends who have the necessary skills. But it’s better to ask yourself the question - how to learn how to work with electric welding on your own, so as not to be dependent on anyone. Today when home welding equipment has ceased to be a problem, the ability to carry out such work, especially for the owner of individual housing, is an invaluable plus, since many problems will simply cease to exist.

But first of all, you need to understand the basic concepts of electric welding and purchase equipment. Welding is technological process where the quality of work directly depends on the equipment of the workplace.

The very essence of electric welding is as follows. The power plant generates a powerful welding current, which is supplied to the work station through cables. An electric welding arc is created between the electrode and the surface of the metal to be welded - a stable discharge, characterized by the highest temperature values. This leads to melting of the metal and filler material. A so-called weld pool is formed - an area of ​​the melt, controlling and directing which the welder forms a seam. After the arc is removed, the molten metal crystallizes and a strong monolithic connection of parts is created.

This very simplified scheme is implemented in several welding technologies:

• most widespread is manual arc welding, which, according to existing terminology, has the abbreviation MMA (from the English name " Manual Metal Arc»). main feature- the use of fusible electrodes with a special coating. Benefits - no extra complexity required technical support, gas equipment. The disadvantage is the possibility of welding only with ferrous metals or stainless steel.

In the vast majority of cases, if welding is considered at the household level, then this technology is meant.

• TIG welding technology allows you to work with alloyed steels and some non-ferrous metals. The term " Tungsten Inert Gas speaks for itself: tungsten and inert gas. In this case, the arc is created between the surface to be welded and the infusible tungsten electrode, and a filler rod of one type or another is introduced as a filling. At the same time, a protective inert gas is constantly supplied through the welding torch with a heat-resistant ceramic nozzle, which ensures the cleanliness of the seam.

Welding according to this technology has a lot of advantages, but it requires special equipment and highly skilled workers.

Metal Inert Gas - Metal Active Gas) is one of the most advanced modern technologies, which is increasingly used by home craftsmen. The process from cooking also takes place in an environment of inert or active gases with automatic supply of filler material ( welding wire) which plays the role of an electrode.

This technology allows seams High Quality in any plane and with a very high performance. To some extent, it is even simpler than M MA, but requires complex and rather bulky equipment - the welding machine itself, the wire feeder, the gas-balloon device, the burner with a special sleeve through which the wire and shielding gas are poured.

• There is also spot electric welding - SPOT, which finds the widest application, in particular, in the body sections of car service enterprises. It will also require special sophisticated equipment, and is practically not used at home.

Manual arc welding MMA - what is required for work?

Any beginner always starts by mastering the techniques of manual arc welding (MMA), so all the questions discussed below will be devoted specifically to her.

To start practicing on your own, you need to prepare certain equipment, equipment and supplies.

arc welding machine

For welding using MMA technology, one of three types of devices is used:

• A welding transformer is one of the simplest types of equipment. The principle of operation is elementary - the mains voltage is 220 V (or 380, for three-phase network) is converted to a lower one, of the order of 25 - 50 V, but due to this, the value of the current increases sharply. The advantages of such a circuit are its simplicity, high reliability and ease of maintenance, high performance power. Such devices are inexpensive, which, probably, largely determines their prevalence.

The transformer has much more disadvantages - a welding arc from alternating current does not differ in stability, cases of sticking of electrodes are not uncommon, large spatter of metal, seams are not accurate. In addition, special electrodes will be required specifically for the “change”. Welding transformers are very dependent on the mains voltage, and in the process of operation they themselves can seriously “sag” the network. They do not differ in compactness and lightness. In a word, it is undesirable to start training with such equipment. As a rule, good skills are required to work on such devices.

• Welding MMA rectifiers differ from transformers in that they give a direct current at the output. It is much easier to work with them, as the "permanent" arc is much more stable, and the seams are more accurate.

But, shortcomings remain- the same massiveness and overall dimensions, even more than that of welding transformers, dependence on the supply voltage and a large load on the network. At a price they are more expensive than transformer devices.

• Without exaggeration, we can say that literally a revolution in welding technology was made by devices operating on an inverter circuit. The mains alternating voltage of 220 V with a frequency of 50 Hz goes through a whole cascade of frequency and amplitude transformations, and at the input the required direct current with the highest degree of stabilization. All processes are controlled by a microprocessor assembly, which allows you to make the required adjustments with a high degree of accuracy.

Most modern solution- welding inverter

All this gives a whole "bouquet" of advantages of such a device:

- The equipment calmly tolerates quite serious fluctuations in m = mains voltage, which is especially important in suburban villages, where such problems are a very common occurrence.

- At the same time, inverters, in comparison with other devices, have minimal energy consumption - they practically do not overload the network.

- Stabilized current and the possibility of its fine adjustment allow you to perform accurate and neat seams. There is practically no spatter.

- The device is compact and lightweight.

A wide range of such devices is produced - from household-class inverters to professional equipment. For beginner welders the most optimal solution. Prices for high-quality inverters are quite high, but, firstly, they tend to decrease, and secondly, such a one-time purchase will fully justify itself. And a lot of inexpensive devices of a very dubious assembly appeared on sale. Therefore, it is very important to approach the problem correctly. inverter selection - You need to pay attention to a number of important nuances:

• Maximum welding current. If the device is to be used in household, then, as a rule, stop on models with a value of 150 - 200 A. this is quite enough to work with electrodes with diameters up to 4 mm.
• Resistance of the electronic circuit to mains voltage fluctuations. Quality inverters must withstand fluctuations within ± 20 ÷ 25 %.
• The inverter must have a forced cooling system that works constantly when the power is on, or equipped with automatic equipment that starts ventilation at a certain temperature of the radiators.
• We should not forget about the power consumption of the device - it can be on the order of 2 ÷ 3 kW for small models, but can reach even more significant values ​​for devices semi-professional or professional class.
• What about m many simply do not know: the parameter that determines the permissible duration of the welding process is the on-time (ST). No device can work without interruptions, and the parameters must indicate the PV, expressed as a percentage of the total duration of the equipment. For household models, this usually amounts to about 40% - nothing can be done, this is the price for the compactness of the device. In practice, this means that the "rest" period, in this case, is 1.5 times longer than the welding time, for example, 1 minute of continuous work will then require at least a minute and a half pause.
• For novice welders, it will be very convenient if some useful functions are implemented in the apparatus circuit:

- "HotStart" greatly facilitates the initial ignition of the welding arc. The electronics automatically increases the current value at the moment of ignition in impulses.

- "ArcForce" will help to cope with the eternal problem of beginners - sticking of the electrode to the metal surface. With a decrease in the required gap between the electrode and the metal, the current increases, preventing this trouble.

- "AntiStick" - a function that will prevent the machine from overheating if sticking still could not be avoided. In this case, the power will simply turn off automatically.

One more important advice. « Achilles heel» inverters is a certain complexity of carrying out repair work in the event of a circuit failure. When choosing a device, it is better to give preference to models with a multi-board layout of the electronic circuit. Buying such devices is a little more expensive, but the diagnosis of breakdowns becomes easier, maintainability is much higher.

Video: how to choose a welding inverter

Welding leads, electrode holder, ground clamp

Welding inverters, as a rule, are already equipped with wires, an electrode holder and a ground clamp. However, when buying these elements, you should also pay close attention - sometimes you can run into low-quality products.

• Welding wires must be in flexible rubber insulation, have reliable brass contact plugs suitable for the connectors of a particular machine. The cable cross section must be at least 16 mm² if the device is designed for currents up to 150 A, 25 mm² - at 200 A and even 35 mm² if it is supposed to work with currents of 250 A and above. Do not chase long wires or extend them yourself - this can lead to an overload of the electronics and the failure of the inverter.
• The electrode holder is the most important element of the welder's equipment, since it is the master who manipulates it in the process of work. Do not use homemade "plugs" for work - this is quite dangerous in terms of getting light burns to the eyes or electric shock. by the most widespread and convenient today are pliers-type holders - “clothespins”. Some are convenient, allow easy and quick replacement of the electrode, are well insulated on all sides and provide proper safety.

One of the most common - holders - "clothespins" of the pliers type

The holder must have a reliable clamp for the electrodes, allowing them to be placed not only perpendicularly, but also at an angle of 45 º. It is necessary not to be too lazy and check the material of the contact part - there should be copper or brass, but not copper-plated steel. This is a clear sign cheap counterfeit, which is easy to detect with a small magnet. It is necessary to check the reliability of electrode fixation, especially of small diameter (2 mm) - this is often a problem for low-quality pliers-type holders.

An important factor is the convenience of the holder, its balance, "weight distribution" - working with it should not cause rapid hand fatigue. It should have a handle long enough to allow the most comfortable hand position, a corrugated surface to prevent slipping in a mittened palm. Do not forget that for the holders the maximum value of the welding current is also determined.

• The clamp for connecting the ground must have a powerful spring, reliable connection with a wire, brass contacts for crimping a metal workpiece, connected by a copper bus.

Welder equipment

• First of all, for welding you will need a mask or shield. Shields often come with inverters, but they have an inconvenience - it must be held with a free hand, and this is far from always possible. It is better to buy a full mask.

This piece of equipment protects the eyes from light burns, covers the face from splashes of metal or sparks, and the respiratory organs, to a certain extent, from rising gases. At the same time, the light filter should provide good visibility of the superimposed seam when the arc is ignited - the selection is made individually. The light filter must be covered with protective glass.

The mask itself is made of heat-resistant plastic. It should not be heavy and bulky, causing rapid fatigue. It is necessary to check the convenience of the headband and its fixation in the desired position, the possibility of adjustment to the required size.

Masks - "chameleons", equipped with special liquid crystal filters that instantly change light transmission at the moment of ignition of the arc. Convenience is undeniable - there is no need to constantly fold back the mask for visual control of the completed seam, and the process of ignition of the arc is also simplified. Such masks have a certain degree of adjustment of the speed of response and the degree of dimming - this is another significant advantage. The disadvantage they have is a rather high price.

• For work, you will need special clothes, sewn from their durable dense fabric, which excludes instant melting or burning when sparks hit (e.g. tarpaulin) Patch pockets on a jacket or pants are strictly prohibited.

Shoes should be leather, completely closed, its top should be securely covered with trousers. Hands must be protected with leather or thick canvas mittens or gloves (gaiters) with long cuffs that completely cover the wrist area.

• For the production of welding work, in addition, you will need a special hammer for chipping slag, iron brush for cleaning the surface of the metal. Cutting blanks and cutting parts (chamfering, etc.) will require a “grinder” machine with cutting and grinding wheels.

What electrodes to use?

Electrode represents a steel rod coated with a layer of coating. The rod is both a conductor for the welding current and a filler material. The coating, when exposed to high temperatures, creates a protective layer of slag and gas, which protects the weld from instantaneous oxidation by oxygen and nitrogen in the air.

It is very important to choose the right electrodes

There are situations when the equipment is good, and everything seems to be done according to the rules, but the weld does not work. Perhaps the reason lies in the wrong selection of electrodes. Alas, many novice craftsmen select them, focusing only on the thickness of the rod section, losing sight of the rest of the characteristics. Meanwhile, the classification of electrodes is quite complex and diverse. Of course, you can get advice when buying, unless of course the seller himself understands this. But you can try to deal with some issues on your own.

For example, an electrode E42 A-U OHI-13/45— 3.0-UD (GOST 9966-75) or E-432(5) – B 1 0 (GOST 9967-75). What can numbers and letters tell about?

• E42 A– a special designation that speaks of the mechanical and strength qualities of the created seam. Characteristic more required for engineering calculations.
• UONI -13/45 - the brand of the product is encrypted here. assigned by the manufacturer.
• 3,0 – the diameter of the metal rod is 3 mm.
• Letter "U" says that it is designed for welding carbon or low alloy steels - what is most often required at home. You can find designations "L", "T", "V" are electrodes for doped and in instrumental steels of various types, and "N" - to create a surfacing layer on the metal surface.
• Letter "D" in this example, it speaks of a thick coating. Thin layer will be marked "M" , middle - "FROM" and very thick "G". Preference should be given to a thick coating.

According to the following GOST, the decoding is as follows:

• E-432(5) – information for specialists about physical and chemical properties weldable additive.

"B" is a coating classification. In the given example, the main one. Besides You can find the following designations:

- "BUT" - acid type coating, suitable for constants, And for change, for any types of seams, but gives strong spatter.

- "B" - the main one, used for welding powerful thick parts using reverse polarity.

- "R" - rutile coating - one of the most common, perfect for a novice welder and for work at home.

- "C" - coating with cellulose component. It is very convenient for large-scale work, but requires special qualifications of the welder, as it does not tolerate overheating.

- "RC", "RTsZh" — combined type. The letter "Zh", in addition, indicates the inclusion of iron powder in the composition. Mainly used by skilled professionals for special kind works.

• The next figure indicates the spatial arrangement of the seams that can be performed with this electrode.

— "one" - universal;

- "2" - everything except vertical top down;

— "3" - the "ceiling" and the vertical are unacceptable, just as in clause 2;

- "4" - the electrode can only perform lower seams.

• The last digit of the marking is an index indicating the parameters of the required welding current. The data is summarized in a special table, taking into account both the type of current, and the value of the open-circuit voltage of the device, and the desired polarity. In order not to go into details - just a few words about what needs to be considered. There are ten gradations in total, from «0» before "nine" . For alternating current, any, except «0» . When "permanent", the polarity of the connection will not matter for the indices "1", "4", "7" . electrodes "2", "5" And "8" - exclusively for direct polarity, and "0", "3", "6" , And "nine" - only for reverse.

The diameter of the electrodes is selected depending on the thickness of the parts to be welded. You can easily focus on the following parameters:

— For blanks up to 2 mm thick — Ø 1.5 ÷ 2.5 mm;

- 3 mm - Ø 3.0;

- 4 ÷ 5 mm - Ø 3.0 ÷ 4.0;

- 6 ÷ 12 mm - Ø 4.0 ÷ 5.0;

- over 12 mm - Ø 5.0.

Video: classification of electrodes for manual arc welding

Workplace preparation

To get started practical training, you need to prepare yourself a workplace:

• Work best for fresh air and open space - the probability of ignition of building structures is excluded, less exposure to toxic fumes.
• There should be no flammable materials or liquids near the workplace.
• In case of fire, fire extinguishing agents should be prepared - water, a flame-retardant cape made of thick fabric, sand. At the same time, water can be used to extinguish the flame only when the apparatus is completely de-energized.

The optimal solution is a metal welding bench

• Work best for metal workbench. You should consider the issue of fixing workpieces (vices, clamps, etc.). )
• The extension cord must be sized to suit the peak power consumption of the welding machine.
• Before starting work, it is necessary to provide measures to exclude the appearance of strangers, and in particular children.

First practical steps

If everything is ready, you can proceed to practical actions. To begin with, it is best to prepare a sheet of metal, cleaned of dirt and rust - it is better to work out the first steps on it, without rushing to immediately weld any parts.

A mass clamp is attached to the workpiece. Good contact at the junction is very important - it should be cleaned with a metal brushed

It is best to start training with electrodes Ø 3 mm - it is easier to “fill your hand” with them. The value of the welding current in this case will be about 80 - 100 A. The electrode is inserted into the holder, the reliability of its fastening is checked.

• The first "exercise" will be to strike and hold the welding arc. To do this, after turning on the device and lowering the mask, you need to either strike the electrode on the metal surface or tap several times on one place. A spark must appear, and now the most important thing is to keep the burning arc. To do this, it is necessary to strictly maintain the gap between the electrode and the metal surface. The position of the electrode is approximately 30º from perpendicular to the surface.

A normal gap is considered to be one that is approximately equal to the thickness of the electrode rod - this is called a short arc. When inverter welding using high-quality and dry electrodes, there are usually no problems with arc stability. With an increase in the gap to 4 - 5 mm, a long arc is obtained, which will not give a high-quality seam. Excessive approach of the electrode to the surface may result in its sticking. In this case, you should immediately swing the holder to the side until the rod overheats.

When maintaining the arc, it should be remembered that the electrode constantly burns out, and its position relative to the metal surface must be corrected.

• Now you need to clearly understand the structure of the melted metal in the arc area. At the beginning of heating, a red liquid spot appears - this is not metal yet, but a melted coating of the electrode, which created a protective layer. After 2-3 seconds, a bright orange or even whitish drop with a slight tremor or ripples on its surface will appear in the center of this spot - this is the weld pool, the area of ​​molten metal. It is important to learn to clearly distinguish between liquid slag and the bath itself - the quality of the superimposed seam will also depend on this.
• As soon as the bath has formed, we begin to try to carry out its movement, smoothly moving the electrode, without changing the gap. A drop of metal always moves to an area of ​​elevated temperature, so the bath will also tend to follow the arc. For its part, the arc pressure somewhat pushes the bath in the opposite direction. Having worked practically and understood this principle, you can try to form a bead of weld metal on the surface of the sheet.
• For some complication of the task, it is best to outline a line on the metal surface, which is to be maintained when creating a welded bead. The electrode will move along the line with small oscillatory movements to the side - as shown in the diagram.

After applying this “seam”, it is necessary to let it cool, and then chop off a layer of slag in order to visually assess the quality. You may need to adjust the current strength. This, for example, will be noticeable in uncooked areas - the current is clearly insufficient. A higher value may cause the sheet to burn through. All this is determined only experimentally, it is difficult to give any clear recommendations.

The first exercise - creating smooth rollers

The porosity of the seams, the inclusion of slag particles in the metal structure is not allowed - this connection is not durable.

In the course of practice, it will be possible to decide which direction of welding will be most convenient - towards you or away from you, pulling the bath behind the electrode or vice versa, pushing it forward. Many craftsmen advise nevertheless to carry out welding, if smooth and high-quality rollers begin to turn out, you can proceed to the next stage - welding two workpieces.

• Welds by spatial position are lower, on a vertical plane (horizontal or vertical) and ceiling. Of course, you need to start from the lower ones - the ability to perform the rest will not come immediately, as experience is gained.

• According to the location of the mating parts, the seams are divided into butt, corner, tee and lap. Each of them has its own characteristics of overlay, electrode movement, cutting and exposure of workpieces.
• Welding of two parts begins with tacks, which will ensure the stable position of the parts when applying the main seam. Usually, for tacking, the current is inserted by 20-30% more, while working on a short arc. In this case, the tacks should not be closer than 10 mm from the edge of the workpieces or near the holes. After applying the tacks, it is possible to check the correct position of the parts and make the necessary adjustments.

• First, you should learn how to apply single-layer seams on thin, 3-4 mm blanks. More complex options, with root welding and filling, can be mastered, years with the simplest techniques, steady skills will be achieved.

You should not be afraid of such first failures - experience will definitely come

In a word, everything else will depend only on the diligence and regular practical training of a novice welder. It is good if there is an opportunity to contact a specialist so that he can evaluate the results. If not, you can compare the results of your work with the videos shown on the Internet with master classes in arc welding. Experience, hardness of hand, the ability to choose the right parameters and self-confidence will definitely come.

Video: manual arc welding master class