How to learn to cook with electric welding yourself. How to cook using inverter welding with electrodes? How to choose the right electrodes for welding

We invite you to watch a video tutorial about welding for beginners, the necessary equipment and all the nuances

Welding is one of the rather complex, but extremely popular technologies for working with metals. Wherever you look, welded joints are always used. Not a single industrial production, construction company, repair or service enterprise can do without this process. Welding becomes indispensable in the construction and improvement of one’s own home.

But here’s the problem: welding work requires a certain level of preparedness. You can, of course, if necessary, contact welders through advertisements, or contact your friends who have the necessary skills. But it’s better to ask yourself the question - how to learn to work with electric welding yourself, 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 an individual home, 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 a 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 through cables to the work station. An electric welding arc is created between the electrode and the surface of the metal being 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 ​​\u200b\u200bthe melt, by controlling and directing which the welder forms the seam. After removing the arc, crystallization of the molten metal occurs and a strong monolithic connection of the 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"). The main feature is the use of fusible electrodes with special coating. Advantages - no particularly complex technical support or gas equipment is required. The disadvantage is that welding can only be done with ferrous metals or stainless steel.

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

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

Welding using this technology has a lot of advantages, but it requires special equipment and highly qualified workers.

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

This technology allows you to make high-quality seams in any plane and with very high productivity. To some extent it is even simpler than M MA, but requires complex and rather bulky equipment - the welding machine itself, a wire feeder, a gas cylinder device, a torch with a special sleeve through which the wire and shielding gas flow.

• There is also spot electric welding - SPOT, which is widely used, in particular, in the body areas of car service enterprises. It also requires 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 it.

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

Arc Welding Machine

To carry out welding work 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 of 220 V (or 380, for a three-phase network) is converted into a lower one, about 25 - 50 V, but due to this the current value increases sharply. The advantages of such a circuit are its simplicity, high reliability and ease of maintenance , high power levels. Such devices are inexpensive, which probably largely determines their prevalence.

The transformer has many more disadvantages - the welding arc from alternating current is not stable, there are frequent cases of electrodes sticking, large spattering of metal, and the seams are not neat. In addition, special electrodes will be required specifically for “change”. Welding transformers are very dependent on the mains voltage, and during operation they can seriously drain the network. They are not distinguished by their compactness and lightness. In a word, starting training with such equipment is undesirable. As a rule, working on such devices will require good skills.

• MMA welding rectifiers differ from transformers in that they produce direct current at the output. It is much easier to work with them, since the “constant” arc is much more stable, and the seams are more accurate.

However, shortcomings remain– the same massiveness and dimensions, even larger than those of welding transformers, dependence on the supply voltage and a large load on the network. They are more expensive in price than transformer devices.

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

The most modern solution - welding inverter

All this gives a whole “bouquet” of advantages of such a device:

— The equipment can easily withstand quite serious fluctuations in the mains voltage, which is especially important in suburban villages, where such problems are a very common occurrence.

— At the same time, inverters, compared to other devices, have minimal energy consumption - they practically do not overload the network.

— Stabilized current and the possibility of its precise adjustment allow you to make precise and neat seams. There is virtually no spattering.

— The device is compact and lightweight.

A wide range of similar devices is produced - from household-grade inverters to professional equipment. For beginner welders, this is 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 quite a few inexpensive devices of very dubious assembly have appeared for 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 planned to be used in a household environment, 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 changes in mains voltage. High-quality inverters must withstand fluctuations within ± 20 ÷ 25%.
• The inverter must have a forced cooling system that operates constantly when the power is on, or be equipped with an automatic system that starts ventilation at a certain radiator temperature.
• We should not forget about the power consumption of the device - it can be of the order of 2 ÷ 3 kW for small models, but can reach larger values ​​for devices semi-professional or professional class.
• What about m Many people simply don’t know: the parameter that determines the permissible duration of the welding process is the on-time (ON). No device can operate without interruptions, and the parameters must indicate the duty cycle, expressed as a percentage of the total duration of operation of the equipment. For household-class models, this is usually about 40% - nothing can be done, this is the price to pay 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.
• It will be very convenient for novice welders if some useful functions are implemented in the device circuit:

— “HotStart” significantly facilitates the initial ignition of the welding arc. The electronics automatically pulse increases the current value at the moment of ignition.

— "ArcForce" will help to cope with the eternal problem of beginners - sticking of the electrode to the metal surface. By reducing the required gap between the electrode and the metal, the current increases, preventing this nuisance.

— “AntiStick” is a function that will prevent the machine from overheating if sticking cannot be avoided. In this case, the power will simply turn off automatically.

Another important tip. The “Achilles heel” of inverters is the certain difficulty 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 electronic circuit layout. Buying such devices is a little more expensive, but diagnosing breakdowns becomes easier, and 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 purchasing, you should also pay close attention to these elements - sometimes you can run into low-quality products.

• Welding wires must be in flexible rubber insulation and have reliable brass contact plugs suitable for the connectors of a particular device. 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 intended to work with currents of 250 A and higher. You should not chase a long length of wires or extend them yourself - this can lead to overload of the electronics and failure of the inverter.
• The electrode holder is the most important element of a welder’s equipment, since it is what the master manipulates during the work process. You should not use homemade “forks” for work - this is quite dangerous in terms of light burns to the eyes or electric shock. The most common and convenient today are plier-type holders - “clothespins”. Some are convenient, allow you to quickly and easily replace the electrode, are well insulated on all sides and provide adequate safety.

One of the most common are plier-type “clothespin” holders.

The holder must have a reliable clamp for the electrodes, allowing them to be placed not only perpendicularly, but also at an angle of 45º. You need to take the time to check the material of the contact part - it should be copper or brass, but not copper-plated steel. This is a clear sign a cheap fake that can be easily identified with a small magnet. It is necessary to check the reliability of fixation of electrodes, especially small diameters (2 mm) - this is often a problem with low-quality plier-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 you to take the most comfortable hand position, and a corrugated surface to prevent slipping in the palm of your hand wearing a mitten. Do not forget that the maximum welding current value is also determined for the holders.

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

Welder equipment

• First of all, for welding work you will need a mask or shield. Shields often come with inverters, but they have an inconvenience - you need to hold it with your free hand, and this is not always possible. It is better to purchase a full mask.

This piece of equipment protects the eyes from light burns, covers the face from metal splashes or sparks, and the respiratory system, to a certain extent, from rising gases. At the same time, the light filter must provide good visibility of the seam being applied when the arc is ignited - 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 comfort of the headrest 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 conductivity at the moment of arc ignition. The convenience is undeniable - there is no need to constantly fold back the mask to visually control the completed seam, and the process of igniting the arc is simplified. Such masks have certain degrees of adjustment of response speed and degree of darkness - this is another significant advantage. Their disadvantage is their rather high price.

• To work, you will need special clothing, made of durable, dense fabric that prevents instant melting or burning when exposed to sparks. (eg tarpaulin) Patch pockets on a jacket or pants are strictly prohibited.

Shoes must be leather, fully closed, and their tops must be securely covered by the legs. Hands must be protected with leather or thick canvas mittens or gloves (gaiters) with long cuffs that completely cover the wrist area.

• To carry out welding work, in addition, you will need a special hammer for chopping slag - cleaver, iron brush for cleaning metal surfaces. Cutting workpieces and cutting parts (chamfering, etc.) will require a grinder machine with cutting and grinding wheels.

What electrodes should I use?

Electrode represents steel rod covered with a layer of coating. The rod is both a conductor for welding current and a filler material. Coating, when exposed to high temperatures, creates a protective layer of slag and gas, protecting the weld from instant 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 incorrect selection of electrodes. Alas, many novice craftsmen select them, focusing only on the thickness of the rod section, losing sight of the other characteristics. Meanwhile, the classification of electrodes is quite complex and diverse. Of course, you can get advice when purchasing, if, of course, the seller himself understands this. But you can try to figure out 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 us?

• E42 A– a special designation indicating the mechanical and strength properties of the seam being created. A characteristic more required for engineering calculations.
• UOHI -13/45 – The brand of the product is encrypted here. which is assigned to it by the manufacturer.
• 3,0 – the diameter of the metal rod is 3 mm.
• Letter "U" indicates that it is intended for welding carbon or low-alloy steels - what is most often required at home. You can find designations "L", "T", "V" - these are electrodes for alloyed 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 thick coating. A thin layer will be indicated "M" , average - "WITH" and very thick - "G". Preference should be given to thick coating.

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

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

"B" is a classification of coating coating. In the example given - the main thing. Besides You can find the following designations:

- "A" — acid-type coating, suitable for permanent, And for a break, for any types of seams, but produces strong spattering.

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

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

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

- “RC”, “RCZh” — combined type. The letter “F”, in addition, indicates the inclusion of iron powder in the composition. Mainly used by qualified specialists for special types of work.

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

— "1" - universal;

- "2" - everything except vertical top down;

— "3" - “ceiling” and vertical are unacceptable, just as in point 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 the type of current, the value of the open circuit voltage of the device, and the required polarity. Without going into details, just a few words about what needs to be taken into account. There are ten gradations in total, from «0» to "9" . For alternating current, any can be used except «0» . When “constant”, the polarity of the connection will not matter for indexes "1", "4", "7" . Electrodes "2", "5" And "8" - exclusively for straight polarity, and "0", "3", "6" , And "9" - only for reverse.

The diameter of the electrodes is selected depending on the thickness of the parts being welded. Simplified, you can focus on the following parameters:

— For workpieces 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

Preparation of the workplace

To start practical exercises, you need to prepare yourself a workplace:

• It is best to work in the fresh air and open space - there is no possibility of fire in the building structures, and there is less exposure to toxic fumes.
• There should be no flammable materials or liquids near the workplace.
• In case of fire, you should prepare fire extinguishing agents - water, a fire-resistant cape made of thick fabric, sand. In this case, water can be used to extinguish the flame only when the apparatus is completely de-energized.

The optimal solution is a metal welding workbench

• It is best to work on a metal workbench. You should consider the issue of fixing workpieces (vises, clamps, etc.). )
• The extension cord must have a cable cross-section that matches the peak power consumption of the welding machine.
• Before starting work, it is necessary to take measures to exclude the appearance of strangers, and especially 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 practice the first steps on it, without rushing to immediately weld any parts.

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

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

• The first “exercise” will be to ignite and hold the welding arc. To do this, after turning on the device and lowering the mask, you need to either scratch the electrode on the surface of the metal, or knock several times on one place. A spark must appear, and now the most important thing is to keep the arc burning. 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 30 º from the perpendicular to the surface.

A normal gap is considered to be 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. Increasing the gap to 4 - 5 mm results in a long arc, which will not produce a high-quality seam. Bringing the electrode too close to the surface may result in it sticking. In this case, you should immediately swing the holder to the side before the rod begins to overheat.

When maintaining an arc, remember that the electrode is constantly burning out, and its position relative to the metal surface must be adjusted.

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

After applying this “seam,” you need to let it cool and then chip off the slag layer to visually assess the quality. Amperage adjustments may be required. This, for example, will be noticeable in uncooked areas - the current is clearly insufficient. An increased value may lead to burning of the sheet. All this is determined only experimentally; it is difficult to give any clear recommendations.

The first exercise is to create even rollers

Porosity of the seams and inclusion of slag particles in the metal structure are not allowed - this connection is not durable.

During 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 still advise welding, if smooth and high-quality beads begin to be obtained, you can move on to the next stage - welding two workpieces.

• Welded seams in spatial position can be lower, on a vertical plane (horizontal or vertical) and ceiling. Of course, you need to start from the bottom - the ability to perform the rest will not come immediately, as you gain experience.

• Based on the location of the mating parts, seams are divided into butt, corner, tee and overlap. Each of them has its own characteristics of application, electrode movement, cutting and positioning of workpieces.
• Welding of two parts begins with tacks, which will ensure a stable position of the parts when applying the main seam. Usually, for tack welding, the current is inserted 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 close to the holes. After applying 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 sutures on thin, 3-4 mm workpieces. More complex options, with root boiling and filling, can be mastered; years with the simplest techniques, stable 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 efforts and regular practical training of the novice welder. It would be good if there was an opportunity to contact a specialist so that he could evaluate the results obtained. If not, you can compare the results of your work with videos shown on the Internet with master classes on arc welding. Experience, steadiness of hand, ability to choose the right parameters and self-confidence will definitely come.

Video: master class on manual arc welding

The profession of a welder has long been firmly established in many sectors of industry and households. There is a need for it almost everywhere. The availability of modern welding equipment allows you to both learn how to weld by yourself and master the profession at a more serious level.

Elements required for a welder

In order to perfectly master the technique of working with welding equipment, you will need to understand not only the physical processes when working with metal, but also a set of knowledge about welding machines, as well as various malfunctions, technology features, and other pitfalls. You need to be able to understand the intricacies of the welding profession at every stage - from the preparatory stage to the final stage. In vocational schools, training for this profession takes two to three years.

What do you need to understand before learning how to cook with electric welding?

• be able to correctly select the mode for working with various materials (steel, alloys, non-ferrous metals);
• know various techniques for creating a weld;
• be able to choose electrodes and welding wire wisely;

How to learn electric welding yourself?

If the goal is not to become a top-class professional, then it will be enough to master the key techniques and understand the basic concepts, and you can already experiment with welding work in the farmstead.

So where to start?

First of all, you will need a welding machine and electrodes. It is better to start with electrodes with a diameter of 3 mm - they are suitable for most tasks and do not put a very heavy load on the electrical network. The devices are divided into three categories based on their operating principle: transformer, rectifier, and inverter. Inverters are the most compact, lightweight and easy to use for beginners.

Then you need to choose a few metal fragments to practice on. You will need a bucket of water, a hammer to knock down the slag, and a metal brush to clean the surface. In terms of overalls and protective equipment you will need:

• a mask to protect the face and neck with a special light filter (for example, a chameleon mask);
• gloves made of thick fabric;
• workwear made of durable fabric, with long sleeves.

Do not forget about safety precautions: there should be no flammable or easily flammable materials nearby, and the electrical network must be able to withstand the loads that arise during operation of the welding machine.

The first steps in learning how to cook using electric welding

Care must be taken to ground the unit - the appropriate clamp must be firmly attached to the part. Then you need to check the cable - how well it is insulated and how well it is tucked into the holder.

After connecting the ground, you can select the current value, depending on the electrode and the materials you intend to work with.

Before lighting the arc, the electrode is positioned relative to the workpiece at an angle of about 60 degrees.

Gradually the electrode will burn out. There is no need to rush to move it. The speed of movement of the electrode depends on many factors - they will be revealed in more detail during practice.

What to do if the electrode gets stuck? It is enough to swing it slightly to the side.

To create a stable welding arc, it is advisable to maintain a distance of 3 to 5 millimeters between the end of the electrode and the surface of the part. In the case of an arc 2-3 mm long that refuses to ignite, the current can be increased.

Features of the welding arc and polarity when creating a seam

When trying to weld a bead, you should try to move the molten metal towards the center of the welding arc.

The electrode moves smoothly horizontally, accompanied by oscillatory movements. Thanks to this, a beautiful and high-quality seam is obtained. To learn how to cook with electric welding, how

professional, you need to know the difference between welding with direct polarity and reverse polarity.

An electric arc is formed when alternating or direct current is supplied from a power source. If the positive pole of the power supply (anode) is connected to the part, then this means that arc welding has straight polarity.

And if the negative power pole (cathode) is connected to the part, arc welding with reverse polarity is obtained. The electric arc causes the metal rod of the electrode to melt and mix with the molten material of the product, forming a so-called weld pool. In this case, slag is formed, which comes to the surface.

How to weld correctly using electric welding with different sizes of the weld pool?

Depending on the position of the pool in space, as well as taking into account various welding modes, the design of the parts being connected, the size and shape of the edges, as well as the speed at which the arc moves on the surface, the size of the weld pool may vary. As a rule, its sizes can vary in the range:

• from 8 to 15 mm - width;
• from 10 to 30 mm - length;
• up to 6 mm - depth.

How is arc length calculated? This is the distance from one active spot located on its surface to another (which is located on the molten surface of the electrode). When the electrode coating melts, a gas atmosphere appears near the arc and above the weld pool, which displaces air from the welding zone, preventing it from affecting the molten metal. Also included here are pairs of alloying elements of both the base and electrode metal.

In addition, slag protects from the oxidizing effects of air because it covers the surface of the weld pool. And thanks to it, the metal is cleaned of harmful impurities. Slag is formed as the arc is removed and the metal crystallizes in the weld pool during the formation of the weld.

About technical techniques for forming a seam

Before you learn how to weld using electric welding yourself, you should master various welding techniques for connecting metal parts. Proper maintenance and movement of the electric arc is the key to a high-quality seam. If the arc is too long, the metal will oxidize and become saturated with nitrogen, splash out in droplets, and form a porous structure.

Lapped seam

The welding arc moves forward along the axis of the electrode. In this way, the desired arc length is maintained, which is affected by the melting rate of the electrode. The length of the electrode decreases gradually, just as the distance between it and the weld pool increases. To prevent this, the electrode is supposed to be moved along the axis, maintaining the synchronism of its shortening and movement in the direction of the weld pool.

Ceiling seam

Another type of roller is called a thread roller. Such a bead is formed in the process of moving the electrode along the axis of the welded seam. As for the thickness of the roller, it depends on the diameter of the electrode and the speed at which it moves.

About the width of the roller, we can say that it is usually 2-3 mm greater than the diameter of the electrode. This results in a fairly narrow weld seam. Its strength is not high enough to create a strong structure. How to fix this? When moving the electrode along the axis of the weld, it is enough to move it additionally - across the axis.

T-seam (with one-sided groove)

Transverse displacement of the electrode during operation makes it possible to obtain a sufficient seam width. This is done by back-and-forth oscillations of the electrode, the width of which is determined for each specific case individually. Here you need to take into account the position of the seam, its size, the shape of the groove, the characteristics of the materials, as well as the list of requirements put forward for the design. It is generally accepted that the normal weld width is from 1.5 to 5.0 electrode diameters.

Welding seam with electrode support

It is formed through rather complex, triple movements of the electrode. Exists in several variations. The trajectory of movement in classical arc welding must be such that the edges of the parts that need to be joined are fused, and at the same time enough molten metal must be formed to form a seam of a given shape.

Cutting and joining seams

How to learn how to properly weld torn seams using electric welding? If the electrode has burned out almost completely, you have to stop to replace it. Before resuming work, the slag is removed and the process can continue.

The arc is ignited at a distance of 12 mm from the crater (this is the depression that appears at the end of the weld). The electrode returns to the crater to form a fusion of the new and old electrodes, and then continues its movement along the initially chosen trajectory.

Advantages and disadvantages specific to manual welding

Advantages:

Flaws:

• quite harmful working conditions;
• the quality of seams directly depends on the qualifications of the welder;
• Efficiency and productivity are quite low (compared to other types of welding).

Video: How to learn to cook with electric welding

Welding is used in many sectors of the Russian economy. Welders work on construction sites, creating underground and above-ground structures. They work in automobile factories, energy complexes, agriculture and oil refineries.

In addition, galvanized pipes have a pleasant appearance, so they are often used to create the original design of a building or structure.

Welding of galvanized metal, which is used in construction, is done in the same way.

Do-it-yourself welding is considered a difficult task. Before starting such work, you need to study the rules of the welding process and learn how to perform light welding work for beginners in this matter.

Welding is the most reliable connection of permanent parts. In everyday life, it is widely used in the manufacture of fences using chain-link mesh, greenhouse frames, stoves for bathhouses and garages, or various containers needed in summer cottages. A person with welding skills is able to create real masterpieces of openwork fencing, roof canopies and other household necessities on his or her plot.

What is the basis for the reliability of welding: the basics of welding work

In terms of the strength of creating permanent joints, welding occupies a leading position. This is achieved by heating alloys of various metals using an electric arc, which leads to plastic deformation of the materials used. In this case, mutual penetration of elementary particles of the electrode into the structure of the materials being connected occurs. As a result, molecular bonds with ultra-high strength arise.

Thanks to modern innovative technologies, it is now possible to use laser and electron beams, ultrasound and gas torch flames for welding. But for welding in domestic conditions, electric arc welding remains the most optimal, a source of energy for which various types of welding machines, including inverters, are used to create an electric arc.

Welding methods

The following welding methods exist:

• Gas press, using an acetyl oxygen flame. The advantages of this type of welding are high productivity. Therefore, it is widely used in the oil and gas industry, in particular in the construction of highways for transporting oil and gas, as well as in mechanical engineering.
• Contact, carried out by electric current having a relatively low voltage at a sufficiently high current strength. This method includes the following varieties: butt welding, seam welding and spot welding.

In addition, in some cases, roller and electroslag welding, friction and thermite welding, as well as a number of other varieties, are used.

Choosing the Right Equipment

If you decide to master the technique of welding, then you will need welding equipment. It can be rented or purchased. Currently, retail outlets offer welding machines equipped with a device that allows you to increase or decrease the current. Those who like to do everything with their own hands can make a welding machine from improvised materials. In any case, you will need one of the following electrical energy converters:

1. Transformer for converting alternating current from a household electrical network into the current required for welding work. When choosing a unit of this type, it is necessary to take into account that cheap models will not be able to provide the necessary stability of the electric arc. They are characterized by a “sag” of voltage. Plus they are too heavy.
2. Rectifier. This is a device that converts alternating electric current supplied to consumer networks into direct current. Unlike transformers, these units provide sufficient stability of the electric arc, which, in turn, improves the quality of the weld.
3. Inverter. It converts the alternating current of the household electrical network into the required direct current, with the voltage necessary for high-quality welding. This device is compact and light weight, easy to ignite, fast action and high performance.

** Recommendation. The most effective of the listed devices is considered to be an inverter, characterized by efficiency and high performance.

How to choose the right electrodes for welding

The most common type of arc welding requires electrodes that are designed to supply current to the weld. In most cases, this is a wire consisting of a special melting powder. But for those who are encountering welding for the first time, it is better to use electrodes in the form of solid rods coated with a melting composition. They allow even a beginner to create an even seam. The optimal diameter of the electrode rod for this category of welders is 3 mm. Smaller diameter electrodes are used to join thin sheets of metal, and for use

Larger diameter electrodes require higher power equipment.

Safety of welding work (welder equipment)

Welding work is accompanied by bright light radiation and a lot of splashes of hot metal. Therefore, the welder must take care to protect the skin of his face and eyes from burns. For these purposes, you will need a special shield and mask. But it's not just the face and eyes that need protection. The skin of your hands is more susceptible to burns from flying splashes of melting metal. Therefore, mittens made of canvas or suede are a necessary means of ensuring safety. The ideal option is to have a robe or overalls made of thick canvas or rubberized fabric.

In order to ensure fire safety, in places where welding work is carried out there must be a container of water or other means that protect against fire if an accidental spark hits.

Step-by-step instructions for performing welding work

1. The surface to be welded must be carefully protected. It should be free of dirt and rust.
2. Before starting welding work, you must insert the electrode into the holder of the welding machine and create an electric arc. To do this, it is necessary to cause current movement in the welding zone. This process can be carried out by striking the electrode rod against the metal or by touching it to the surface of the workpiece in the form of tapping.
3. As soon as an electric arc appears, it is necessary to create a gap between it and the surface to be connected. This gap should have a constant value and range from 3 to 5 mm.

** Recommendation. To obtain an even seam without defects, it is necessary that the gap size remains constant throughout the entire welding process. Otherwise, the arc will be interrupted, which will lead to deterioration in the quality of the weld.

1. The angle of inclination of the rod should be 70?. But it can be changed in order to ensure the comfort of welding work.
2. The stability of the electric current supply is also important. It must be taken into account that too much force will cause the metal to melt, and if it is too low, the arc will be extinguished.

After you have mastered the technique of making a bead weld, you can proceed directly to making permanent connections. Work begins with creating an arc. Then the welder proceeds to directly connecting the parts. At the same time, his hand must make oscillatory movements from one element to another. The weld seam (trajectory of movement) can be made in the form of a herringbone, loop, zigzag, etc. At the end of the work, it is necessary to clean the seam from any slag that has formed.

Once you have mastered basic welding skills, you can move on to more advanced welding jobs, making butt, tee, lap, and corner joints in a variety of directions. Once your hand gains confidence, you can begin making more complex products.

Video - manual arc welding for beginners