Electric welding methods. About technical techniques for forming a seam

You can become a welder after 2 years of study at a vocational school or college; in extreme cases, you can take courses. For those who do not want to do this professionally, but simply want to skillfully perform welding seams, the following selection of common welding seams will help.

Welding tools

Purchasing the necessary equipment is an important preparation for successfully performing welding seams. The main device for their creation is a welding machine. Its variations can operate on both direct and alternating current. When working on a welding machine, you need to purchase electrodes.

If electric arc welding is used, then the electrodes at constant current move in one direction, which is determined in accordance with the polarity.

There are several welding machines:

• Transformer . With its help, the electricity supplied by the network is converted into alternating current necessary for the welding process. If you choose a cheap option, you can get a heavy device that will cause difficulties during transportation, as well as high arc constancy and voltage loss during operation.
• Rectifier . It converts alternating current from the mains into direct current for welding. It has almost the same disadvantages and advantages as the previous device. But the quality of the seams after its use is much better, since it maintains the stability of the arc.
• Inverter . Provides constant current and voltage for welding. This is a compact device that provides smooth current regulation; it differs from its analogues in its fast response and easy ignition.

Welding inverters of the new generation are superior in accuracy to transformers, generators and rectifiers previously used for welding; the polarity on them can be set independently. Beginners are recommended to master welding using inverters.

Successful use of these devices depends on the correct concept of polarity. If straight polarity is selected, then the wire with the “minus” goes to the electrode, and the wire with the “plus” goes to the ground terminal. With reverse polarity, everything will work in reverse.

The welding machine is supplied with current through wires with quick-release terminals. The conductors must be made of copper and insulated; they conduct current, and the synthetic film functions as a separator.

Electrodes for metal welding are made from welding wire. But for cast iron, filler wire with a graphite rod is used. Cast iron, unlike steel, is a very brittle material, and its welding must be carried out using a cold method. When welding, you must constantly monitor the heating of its surface, otherwise cracks may occur. The seam is not made in one piece, but in snatches with obligatory forging.

Basics of a novice welder

Mastering welding begins with training sessions on unnecessary pieces of metal. It’s better to stock up on a container of water; if a fire suddenly occurs due to inexperience, you can quickly eliminate the fire. When taking your first steps, you need to be careful and vigilant, even if a small spark jumps off, it will be enough to start a fire:

• On the selected device, the cable insulation and correct insertion into the holder are checked.
• The required current value is set based on the diameter of the electrode.
• An arc is ignited, set at an angle of 60-70 degrees and slowly drawn across the surface to be welded. The part is touched with an arc when sparks come from the electrode. During the welding process, a distance of 5 mm must be maintained between the arc and the electrode. During operation, the electrodes will burn out. If the electrode sticks to the metal when moving, it needs to be swung to the side.
• The arc may not appear the first time, then the current value is increased so that an arc of a constant length of 5 mm is obtained.
• When you manage to light it, you need to try to melt the bead, trying to collect the molten metal towards the center of the arc.

After such training, you can move on to welding 2 parts of metal.

Correct execution of a vertical weld (video)

The video below demonstrates how to make a vertical seam on thin metal, the thickness of which is only 2 mm.
Korean electrodes with a diameter of 2.6 mm are used for welding. Typically, such seams are made at an angle forward, but since a profile is used on which a small gap is made, the work will take place perpendicularly or with a slight counter-slope. To compare the seams, first half of the gap is welded at 45 amperes, and then switched to 60 and 70. Through the light filter you can see that welding is carried out from the bottom of the profile. The result was 2 seams. As you can see, at 70 amps it turns out smoother and neater.

How to weld a ceiling seam using electric welding? (video)

This type of welding seam is performed on the example of thin plates, for which UUNI electrodes with a basic coating are used.
Here are the welding instructions:

• The first movement of the electrode is made in a “herringbone” pattern, and small steps need to be performed. oscillatory movements. When welding a ceiling seam, a current of 85 amperes is used, and it is performed without interruption. Another option for making such a seam is to move the electrode slightly back and then forward.
• After welding all the plates, they proceed to making a semi-ceiling corner seam, which is carried out starting with a small seam and a return, and then the same “herringbone” is used, performed at an angle back. For fillet welds, you need to set a higher current of 90 amperes. You can perform fillet welding using the second method using a back and forth motion.
• The last seams are carried out at the overlap joint of the plates. This is a semi-ceiling joint. Due to the fact that the top plate is thin, the herringbone movements must be performed smoothly in small steps, without moving the electrode too much on it to avoid explosions. Movements on one seam can be combined. The current remains the same - 90 amperes.

The first seam obtained using the herringbone method has no defects. The second seam with a run forward looks more neat, although it has small pores at the beginning. Corner seams, although made in two different ways, look neat and almost the same.

The overlap seam shows that when performing broad movements The electrode produces undercuts due to the thin platinum. At the beginning of the seams there are pores that arose as a result of poor stripping of the metal.

Video tutorial on making welding seams for beginners

The ability to weld seams is characterized by their beauty and quality. To fulfill these requirements you need to have certain skills. They can only be acquired with experience. And for novice self-taught welders, there is no better guide than a professional’s video, which explains in detail how to weld seams correctly and reliably.
The gap between the pipes is 2 millimeters. Melting through the pipe will be carried out with tear-off, using rutile-coated electrodes. Welding is carried out at an angle backwards, pointwise without tearing off the electrode, in the same place until a bead is formed. The actual current in the device will be approximately 110 amperes. The welding progress is demonstrated through a filter and in daylight. Before making a seam, the electrode needs to be bent a little to make welding more convenient. When examining the seam made with a light filter after beating off the slag, you can see that it forms an even bead, only in the place of the lock the author of the video reinforces it with an additional drop.

The main condition for obtaining beautiful turning seams is the use of a suitable welding method and arc placement.

After purchasing the necessary tools and correct execution Before completing the preparatory work, you can independently perform the seams given in the article. And the correctness of their creation can be controlled by comparison with the examples presented in video lessons from welding professionals.

A weld is one of the most reliable ways to connect parts. It is used in industry and general everyday life. Every home craftsman uses welding from time to time. It’s good if he knows how to cook himself, but he often has to turn to specialists. But welding is quite possible to learn. You should start with the simplest: electric welding for beginners is, first of all, learning how to make various seams. More complex work can be performed only after gaining experience. Let's look at the basics of technology and some tricks of the welding process.

Where to start - the preparatory stage

First of all, you need to prepare the equipment. You will definitely need a welding machine, a set of electrodes, a hammer for knocking down slag and a brush. The diameter of the electrode is selected depending on the thickness of the metal sheet. Don't forget about protection. We prepare a welding mask with a special light filter, thick clothes with long sleeves and gloves, preferably suede. You will also need a welding rectifier, transformer or inverter - devices that convert alternating current into the direct current necessary for welding.

Before work, you need to prepare protective equipment, which includes a special mask with a light filter, suede gloves and long sleeves, as well as the necessary tools

Welding process technology

Welding is a high temperature process. To carry it out, an electric arc is formed and held from the electrode to the workpiece being welded. Under its influence, the base material and the metal rod of the electrode melt. As experts say, a weld pool is formed, in which the base and electrode metals are mixed. The size of the resulting pool directly depends on the selected welding mode, spatial position, speed of arc movement, shape and size of the edge, etc. On average, its width is 8-15 mm, length 10-30 mm and depth - about 6 mm.

The electrode coating, the so-called coating, when melted, forms a special gas zone in the arc area and above the bath. It displaces all air from the welding area and prevents the molten metal from reacting with oxygen. In addition, it contains pairs of both base and electrode metals. Slag forms on top of the weld, which also prevents the melt from interacting with air, which negatively affects the quality of welding. After the electric arc is gradually removed, the metal begins to crystallize and a seam is formed that unites the parts being welded. On top of it there is a protective layer of slag, which is subsequently removed.

During the welding process, the electrode coating melts, forming a special gas zone. Inside it, the base metal and electrode are mixed

Basics of electric arc welding

Recommendations on how to cook using electric welding correctly special attention is given to the beginning of the process. It is best to get your first welding experience under the guidance of a specialist who can correct possible mistakes and give useful advice. You should begin work by securely fastening the part. For fire safety purposes, you need to place a bucket of water near you. For the same reason, you should not carry out welding work on a wooden base and be careless with even very small remnants of the used electrode.

We securely fasten the “grounding” clamp. We check that the cable is insulated and neatly tucked into a special holder. We set the calculated value of the current power on the welding machine, which should correspond to the selected electrode diameter. We light the arc. To do this, we install the electrode at an angle of about 60° relative to the product. Slowly move it across the surface. Sparks should appear, now we touch the electrode to the metal and lift it to a height of no more than 5 mm.

If the operation was performed correctly, the arc will light. The five-millimeter gap must be maintained throughout the welding. It should be taken into account that when properly welding metal using electric welding, the electrode will gradually burn out, so we constantly bring it slightly closer to the metal. The electrode should be moved slowly; if it suddenly gets stuck, you will have to slightly swing it to the side. If the arc does not ignite, the current may need to be increased.

Once you can light and maintain the arc without any problems, it’s time to move on to fusing the bead. We light the arc, slowly and smoothly move the electrode horizontally, performing slight oscillatory movements with it. In this case, the molten metal seems to be “raked” to the very center of the arc. The result should be a strong weld with small waves formed by the deposited metal.

If during the process of welding parts the electrode has burned out almost completely, and the seam has not yet been completed, we temporarily stop the work. We replace the used element with a new one, remove the slag and continue working. At a distance of about 12 mm from the depression formed at the end of the seam, which is also called a crater, we light the arc. We bring the electrode to the recess so that an alloy is formed from the metal of the old and newly installed electrode, after which welding of the seam continues.

During the welding process, the electrode makes certain movements, mainly translational, longitudinal and transverse. Their combinations make up various types of seams, the most common ones are shown in the diagram

The arc movement trajectory during the welding process of parts can be carried out in three directions:

• Progressive. Involves moving the arc along the axis of the electrode. This makes it fairly easy to maintain a stable arc length.
• Longitudinal. Forms a thread welding roller, the height of which depends on the speed at which the electrode moves and its thickness. This is a regular seam, but very thin. To secure it, in the process of moving the electrode along the welded seam, transverse movements are also performed.
• Transverse. Allows you to obtain the desired seam width. Performed by oscillating movements. Their width is selected based on the size and position of the seam, the shape of its cutting, etc.

In practice, all three basic movements are used, which are superimposed on one another and form a certain trajectory. There are classic options, however, each master usually has his own handwriting “visible”. The main thing is that during the work the edges of the joined elements are well fused, and a seam of the given shape is obtained.

Features of pipeline welding

Electric arc welding can be used to make a vertical seam, which is located on the side of the pipe, and a horizontal seam along its circumference. As well as ceiling and bottom, located, respectively, above and below. Moreover, the latter is considered the most convenient to perform. Steel pipes are usually butt welded with mandatory penetration of all edges along the height of the walls. To reduce sagging inside the pipe, an electrode inclination angle of no more than 45° relative to the horizontal is selected. Seam height – 2-3 mm, width – 6-8 mm. When overlapping welding, the seam height is about 3 mm and the width is 6-8 mm.

Before we start welding a pipe using electric welding, we carry out the preparatory work:

• Clean the part thoroughly.
• If the ends of the pipe are deformed, cut or straighten them.
• Clean the edges. We clean at least 10 mm of the outer and inner surfaces adjacent to the edges of the pipe to a metallic shine.

Now you can start welding. All joints are processed continuously until complete welding. Rotary and non-rotary joints of pipes with a wall width of up to 6 mm are made in at least 2 layers. With a wall width of 6-12 mm, three layers are performed, more than 19 mm - four. The peculiarity of welding pipes is that each seam that is placed at the joint must be cleared of slag, after which the next one is made. The first seam is the most critical. It should completely melt all edges and blunts. It is examined especially carefully for cracks. If they are present, they are melted down or cut out and the fragment is welded again.

The final layer is made as even as possible with a smooth transition to the base metal

The second and all subsequent layers are performed by slowly rotating the pipe. The end and beginning of all layers must be shifted relative to the previous layer by 15-30 mm. The final layer is performed with a smooth transition to the base metal and with a smooth surface. To improve the quality of welding pipes by electric welding, each subsequent layer is carried out in the opposite direction relative to the previous one, and their closing points are necessarily spaced apart.

Do-it-yourself welding is a rather complicated undertaking. However, if you want, you can still master it. You need to learn the basic rules of the process and gradually learn how to perform the simplest exercises. There is no need to spare time and energy to master the basics, which will become the basis of mastery. Subsequently, you can safely move on to more complex techniques, honing your skills.

Electric arc welding is a method of joining metal parts in which the parts to be joined are melted by an arc discharge in the area of ​​their contact, followed by solidification and the formation of a permanent joint. The heat source for arc welding is a welding arc - a stable electrical discharge in an ionized mixture of vapors of materials and gases, characterized by a high current density and high (4500-6000 ° C) temperature, exceeding the melting point of all known metals.

Welding arc structure

To create an electric discharge, a constant or alternating voltage is supplied to the metal being welded and the welding electrode from a current source (welding machine). As a result, a welding arc occurs between the electrode rod and the metal. Its resistance exceeds the resistance of the electrode and wires, so the main part of the thermal energy is released in the arc.

To form an arc and maintain its combustion, there must be positively and negatively charged particles - electrons and ions - in the space between the electrode and the metal being welded. The process of their formation, called ionization, occurs during ignition of the arc and is continuously maintained during its combustion.

The figure below shows a diagram of the welding arc and the process of seam formation. Under the influence of the high temperature of the arc (1), the electrode (2), its coating (6) and the welded metal (3) melt. At the melt site, a weld pool (4) is formed, into which drops of the molten electrode (5) are transferred. The molten coating (6) forms a gas cloud (7) and a slag bath (8), protecting the metal from exposure to oxygen and nitrogen. As the electrode moves, the metal cools and crystallizes, forming a weld seam (9) with a slag crust (10) on the surface.

Required electric welding components

To be able to weld metal using electric welding, you must have:

• current source (welding machine);
• welding materials (for example electrodes) corresponding to the metal being welded;
• protective clothing (mainly a protective mask);
• hammer and wire brush to remove slag.

Before starting to work with a welding machine, it is necessary to clean the metal being welded from foreign substances and contaminants - oil, paint, rust, scale, etc. Their presence on the metal leads to disruption of the uniformity of the seam and the formation of pores. Cleaning is done with any suitable tools and materials - a wire brush, a hammer, a rag with a solvent (for example, gasoline). Difficult-to-remove contaminants can be treated with a gas burner flame (blowtorch), followed by cleaning with a brush.

Types of welded joints

Used when welding various types welding joints. There are quite a lot of them; the butt ones alone distinguish 32 species. However, there are only four main ones: butt (1), corner (2), T-joint (3), overlap (4). With corner and T-joints, the edges can be connected at any angle to each other.

When the metal thickness is more than 3 mm, it is recommended to cut the edges, which allows you to make a seam running through the entire thickness of the metal. Cutting makes it possible to weld in several seams (layers) of small cross-section, this reduces stress and deformation and improves the structure of the welded joint.

The cutting angle can be different - from 25 to 50°, depending on the thickness of the metal, the type of connection and the requirement for weld strength. At home, when working with small parts, cutting is easiest done on a sharpening machine. When working with large parts, you can use a gas cutter. If cutting cannot be done for any reason, the welding current is increased to weld the metal through the entire thickness.

Assembling the structure before welding

A feature of the welded joint is severe deformation of the structure. As it cools, the weld metal “pulls” the product, breaking its shape. If proper measures are not taken, the shape of the welded structure will be very different from what was planned. Right angles will turn into acute or obtuse, and the flatness of surfaces will be disrupted.

Deformation is combated using rigid assembly and clamps. The connected parts are fixed in a certain position using clamps, clips, ties and other devices. But even a fixed product can fail if “tacks” are not made in the required places - short seams of small cross-section in different places of the structure. The latter must be positioned in such a way that the stresses of the seams are mutually compensated. In butt joints, for example, clamps are made from different sides of the part.

Connection polarity

Working with a DC welding machine provides an additional opportunity to control the welding mode by swapping the connection of the holder cable (electrode) and the ground clamp (material). In normal mode, the electrode is connected to the minus terminal, and the material is connected to the plus terminal. This connection is called “direct polarity” and provides better heating of the material being welded, which is precisely what is necessary in most cases due to the massiveness of the latter.

The physical nature of stronger heating of the metal with “straight” polarity is that the flow of electrons, which represents electric current, moves from “minus” to “plus”, from the cathode to the anode (in this case, to the metal being welded), transferring its motion energy to it and heating in addition to heating from the electric arc.

Sometimes it becomes necessary to reduce the heating of the metal - when welding thin-walled materials (to avoid burn-through) or alloy steels (to prevent burnout of alloying elements). In this case, reverse polarity is used, connecting the electrode to “+” and the material being welded to “-”. In this case, the flow of electrons changes its direction and no longer heats the metal, but the electrode.

The designation of some electrodes contains an indication of the polarity of the connection, which must be observed. But, in essence, any electrode can work at different polarities, except that the quality of welding will vary. If the “native” polarity of the electrode is unknown, you need to work with it, changing it, ultimately choosing the one that ensures best quality welding

Technology of steel welding with coated electrodes

The question - how to learn to cook with electric welding - has only one answer - practice. You cannot become a welding master by studying theory alone. And yet, before starting practical work, it is useful to become familiar with the theoretical foundations.

Arson arc. An arc can occur either in the event of a breakdown of gas (air), or as a result of contact of electrodes with their subsequent removal to a distance of several millimeters. The first method (air breakdown) is only possible at high voltages, for example, at a voltage of 1000V and a gap between the electrodes of 1 mm. This method of arc initiation is usually not used due to the danger of high voltage. When feeding the arc with high voltage current (more than 3000V) and high frequency (150-250 kHz), you can get an air breakdown with a gap between the electrode and the workpiece of up to 10 mm. This method of igniting the arc is less dangerous for the welder and is often used.

The second method of igniting the arc requires a potential difference between the electrode and the product of 40-60V, therefore it is used most often. When the electrode comes into contact with the workpiece, a closed welding circuit is created. At the moment when the electrode is removed from the product, the electrons, which are located on the cathode spot heated by the short circuit, are separated from the atoms and move to the anode by electrostatic attraction, forming an electric arc. The arc stabilizes quickly (within a microsecond). The electrons that leave the cathode spot ionize the gas gap and a current appears in it.

The arc ignition speed depends on the characteristics of the power source, the current strength at the moment of contact of the electrode with the product, the time of their contact, and the composition of the gas gap. The speed of arc initiation is influenced, first of all, by the value. The greater the current value (at the same electrode diameter), the larger the cross section of the cathode spot becomes and the greater the current will be at the beginning of arc ignition. A large electron current will cause rapid ionization and transition to a stable arc discharge.

As the electrode diameter decreases (i.e., as the current density increases), the transition time to a stable arc discharge is further reduced.

The arc ignition speed is also affected by the polarity and type of current. With direct current and reverse polarity (i.e., the plus of the current source is connected to the electrode), the arc initiation speed is higher than with alternating current. For alternating current, the ignition voltage must be at least 50-55V, for direct current - at least 30-35V.

Re-ignition of the welding arc after its extinction due to short circuits by drops of electrode metal will occur spontaneously if the temperature of the electrode end is high enough.

The most convenient way to ignite an arc is to strike the tip of the electrode against the metal. With this movement, an arc occurs and the coating begins to melt. In this case, the electrode does not stick. In order not to leave marks on clean metal, you need to strike along the line of the future seam, moving the electrode to its beginning.

If there is a bead on the tip, it needs to be beaten by tapping the electrode on the metal - preferably on the one to which the “ground” is not connected, otherwise the electrode may stick. If the electrode tip is excessively exposed, it may need to be struck several times to melt the exposed metal to avoid sticking.

Selecting electrode diameter and strength welding current . The diameter of the electrode and the current strength are selected, first of all, taking into account the thickness of the metal being welded. For the initial selection of electrode diameter and current strength, you can use the following table, the values ​​\u200b\u200bof which correspond to the bottom seam.

The strength of the welding current is also indicated in the characteristics of the electrode on its packaging.

When making welds in vertical and overhead positions, electrodes with a diameter of no more than 4 mm are used. If there is a cutting of the edges or it is necessary to fill the gap between the parts, then the root weld can be made with an electrode of a smaller diameter - 2.5-3 mm.

The approximate value of direct welding current can be calculated using the formula I= K d, where I- current strength, TO- coefficient, d- diameter of the electrode. Coefficient TO selected depending on the diameter of the electrode.

This calculation allows you to determine the current value for the bottom seam when welding with direct current. If these conditions change, the formula should be amended:

• If a vertical seam will be welded, an adjustment factor of 0.9 must be entered into the formula. As a result, the formula will take the form I = 0.9 K d.
• When making a ceiling seam, the value of the correction factor must be reduced to 0.8 (I = 0.8 K d). This will result in a smaller volume of molten metal and faster crystallization.
• When welding on alternating current, the value of the welding current should be increased by 10-15A.

The optimal current value must be selected during operation depending on specific conditions.

If a welding transformer or rectifier is used as a current source, the actual current strength may differ from that set on the machine when the supply voltage changes. If it is low (in the evening, for example), the actual welding current will be lower than the value indicated by the switch.

Welding technology

For an electric arc to occur, two conductive elements with opposite charges are required. One is a metal part, and the second is an electrode.

The electrodes used for manual arc welding consist of a metal core coated with a special protective compound. There are also graphite and carbon non-metallic welding electrodes, but they are used for special work and are unlikely to be useful to a novice welder.

When an electrode and metal of opposite polarity touch, an electric arc occurs. After its appearance, in the place where it is directed, the metal of the part begins to melt. At the same time, the metal of the electrode rod melts, being transferred with the electric arc to the melting zone: the weld pool.

How a weld pool is formed. Without understanding this process, you will not understand how to weld metal correctly (To enlarge the size of the picture, right-click on it)

During the process, the protective coating also burns, partially melting, partially evaporating and releasing a certain amount of hot gases. Gases surround the weld pool, protecting the metal from interaction with oxygen. Their composition depends on the type of protective coating. The molten slag also coats the metal, also helping to maintain its temperature. To weld properly, you must ensure that the slag covers the weld pool.

The weld is formed by moving the bath. And it moves when the electrode moves. This is the whole secret of welding: you need to move the electrode at a certain speed. It is also important, depending on the required type of connection, to correctly select its angle of inclination and current parameters.

As the metal cools, a slag crust forms on it - the result of the combustion of protective gases. It also protects the metal from contact with oxygen in the air. After cooling, it is beaten with a hammer. In this case, hot fragments fly away, so eye protection is required (wear special glasses).

How to weld metal correctly

Learning to hold the electrode correctly and move the bath is not enough for a good result. It is necessary to know some of the subtleties of the behavior of the metals being joined. The peculiarity is that the seam “pulls” the parts, which can cause them to warp. As a result, the shape of the product may differ greatly from what was intended.

Electric welding technology: before starting to apply a seam, the parts are connected using tack welds - short seams located at a distance of 80-250 mm from each other

Therefore, before work, parts are secured with clamps, ties and other devices. In addition, tacks are made - short transverse seams laid every few tens of centimeters. They hold the parts together, giving the product its shape. When welding joints, they are applied on both sides: this way the resulting stresses are compensated. Only after these preparatory measures do welding begin.

How to choose a current for welding

It is impossible to learn how to weld using electric welding if you do not know what current to set. It depends on the thickness of the parts being welded and the electrodes used. Their dependence is presented in the table.

But with manual arc welding, everything is interconnected. For example, the voltage in the network has dropped. The inverter simply cannot produce the required current. But even under these conditions you can work: you can move the electrode more slowly, achieving good heating. If this does not help, change the type of movement of the electrode - passing over one place several times. Another way is to use a thinner electrode. By combining all these methods you can achieve good weld even in such conditions.

Now you know how to weld properly. All that remains is to practice the skills. Choose a welding machine, buy electrodes and a welding helmet and start practicing.

To reinforce the information, watch the video lesson on welding.

If you want to learn how to use electric welding, first you should acquire the necessary equipment, since electric welding for beginners is a responsible undertaking. For use at home, even an entry-level welding machine is sufficient. Although, absolutely anyone will do:

• rectifier;
• inverter;
• welding transformer.

It is good if the maximum current exceeds 160 amperes. You should also acquire protective equipment:

• welder mask;
• work gloves;
• clothing made of dense material (not synthetic);
• boots made of rough leather or tarpaulin;
• hammer;
• metal brush.

The only basic safety equipment you need is a fire extinguisher or at least a bucket of water. You must also take all precautions when using electrical appliances.

To learn how to use electric welding, you should remember one simple rule: electrodes must be selected taking into account the thickness of the metal, and the current strength of the device must be set according to the type of electrode.

When working on a welding transformer, a current of 30-40 amperes is set for each millimeter of metal thickness. When using an inverter, the maximum current for a 3 mm thick electrode is 80 amperes, since at 100 amperes it can cut metal. In the case of electrodes of 2 mm thickness, the current is set to 20-30 amperes, and when set to 40 amperes it can cut metal.

Before you start welding, you need to prepare a workplace, as well as workpieces that will be used for training in welding. Using a metal brush or grinder, clean the welding point from rust and dirt. To fix and join the elements to be welded, you need to use clamps or a vice.

Learning how to operate a welding machine starts with something simple – welding beads. To do this, you need to buy electrodes with a diameter of 3 mm. For beginners, ANO-21 or ANO-36, which are considered universal and the most inexpensive, will be enough. It is better to use new electrodes, as old ones sometimes become damp and become unusable.

The ground clamp must be attached to the part, and the electrode must be inserted into the holder.

1. You need to strike the electrode on the metal part, like a match, slowing down slightly. When an arc occurs, it must be held by holding the electrode a few millimeters from the surface of the workpiece and moving it to the side.
2. Tapping is the second method. You need to tap the end of the electrode on the workpiece and immediately tear it off while holding the arc. You need to move the electrode along the workpiece, maintaining a gap of 3 to 5 mm.

You can learn how to weld with a welding machine by first learning how to move the electrode across the workpiece correctly. The inclination should be about 75 degrees in the direction of the arc. By setting the correct current value, the arc will be stable, and the metal and electrode will simultaneously melt. If the current is too high, the metal will start to burn and spatter.

Let's try to cook

Try welding two parts together. Light the arc and begin to move the electrode smoothly along the seam at an angle of 75 degrees. In this case, you should carry out oscillatory movements with a crescent, as if raking the metal from each workpiece to the welded joint. This way you will end up with an even and continuous seam. After the metal has cooled, you need to beat off the slag with a hammer.

The main thing is to practice, and then your skill will begin to improve. In the future, you will be able to master more complex welding techniques, for example, welding vertical or ceiling seams. You will always find application for such abilities in the household.

The most reliable and durable way to connect parts is a welding seam. Today, no production can do without welding; it is also used in everyday life. Almost every home craftsman necessarily uses welding.

Of course, not everyone knows how to weld parts correctly; they have to use the services of professional welders. But if you really want to, you can learn how to weld parts with your own hands.

Electric welding is considered the simplest. This is where the study of the welding process begins. Only after gaining certain experience in obtaining good seam, you can begin to perform complex work. Let's get acquainted with the basics of welding technological process and its nuances.

Before welding begins, the parts are first straightened and then cleaned well. Moreover, it is necessary to clean the parts before starting assembly of the unit. The appearance of weld defects is usually associated with various types pollution:

1. Rust;
2. Oils;
3. Scale.

It is very important to thoroughly clean the metal where the work will be carried out. welding work. This applies to the edges of each part. Any contamination in the gap between the parts being welded must be removed. You can burn out the dirt with a strong flame of a burner, or blow it with a powerful stream of compressed air.

You can clean the surface in a variety of ways:

• A brush with metal bristles;
• Needle cutters;
• Hydrosandblasting systems;
• Fraction;
• Burner;
• Grinding wheel;
• Etching;
• Solvent.

After preparing the tools and material, let's figure out step by step how to properly weld with electric welding.

Excitation of the welding arc

There are several ways to initiate an arc.

Option 1. The welder should touch the metal surface with the tip of the electrode, then quickly move it back a few millimeters (2 - 4). As a result, an arc will appear. Its length is maintained by slowly lowering the electrode. It all depends on the amount of melting. Before an arc forms, the worker's face must be covered with a protective shield.

Option 2. You can excite the welding arc in another way. The welder quickly runs the tip of the electrode along the metal surface, then also quickly raises it a couple of millimeters. An arc will appear between the electrode and the metal surface. When welding, you should strive to maintain a very short arc. Small drops of metal will form near the seam. The melting of the electrode will be smooth and calm. The seam is deep and durable.

If the arc size is too long, the base metal will not melt well enough. During welding, the metal of the electrode will begin to oxidize and strong splashes will appear. The seam after such welding will be uneven, with numerous oxide inclusions.

The length of the arc can be easily determined by the sound of its burning. If the length has standard values, the sound will be monophonic and uniform. A very long arc will begin to make sharp sounds, which will be constantly accompanied by strong pops.

If the arc breaks, it is excited again. The crater where the arc broke is carefully welded. If it is necessary to weld a very important unit that will be operated under an alternating load, and “fatigue” may also occur, it is strictly forbidden to excite an arc directly on the surface of the base metal. If the excitation does not occur along the seam, a “burn” of the metal may occur. At this point, the seam may simply collapse during operation of the part.

First steps

To learn how to weld parts well, first practice on unnecessary metal rollers. There is no need to create connecting seams, you just need to learn how to melt the material correctly. The metal surface should be free of rust and well cleaned.

How rollers are made

The electrode is inserted into the holder. To cause a current to appear in the melting area, it is enough to scratch the surface of the metal with the tip of the electrode, or simply tap the workpiece several times.

When an electric arc appears, the electrode is directed to the workpiece, maintaining a constant gap between the metal surface and the electric arc. The gap should have a constant value and be in the range of 3–5 millimeters.

Important! To obtain a high-quality seam, it is necessary to maintain the same arc length at all times. If you change this value, the arc may be interrupted and the seam will have many defects.

The direction of the electrode is made at a certain angle relative to the plane of the workpiece. The most optimal angle is considered to be 70 degrees. The inclination does not have a specific value, the main thing is that the welder is comfortable. During the work process, the welder himself finds the optimal position for himself, depending on the specificity of the work being performed.

During such practical exercises, you need to learn how to correctly select the current strength so that the supply remains stable all the time. If there is not enough current, the arc will constantly go out. With a very powerful flow, metal penetration will begin. Only through experimentation can you learn how to correctly set the welding mode.

Technique for obtaining a good weld joint

When the rollers begin to turn out smooth, you can try to start making connecting seams. This operation can be performed by a fairly experienced trainee who knows how to weld using electric welding.

The electrode is ignited according to the technology described above. The only difference will be the movement of the welder's hand. She will perform oscillatory movements. The melt will seem to move from one surface of the part to another. Movement can occur along several trajectories:

• Zigzag;
• Loop-shaped;
• Herringbone;
• With a sickle.

For training, you can take a small metal blank. Draw a line along the surface with chalk so that it can be seen through the dark glass of the mask. It is along this that you need to move the electrode in order to get a kind of seam, in the form of any of the above paths.

After the seam has cooled, you need to beat off the slag with a hammer and examine the work done.

When you have a little experience, you can begin to make connecting seams, which have several types:

• T-bars;
• Butt;
• Angular;
• Overlapping.

In addition, such seams can be horizontal and vertical, and can be welded in different directions.

Only after numerous trainings can you achieve uniform hand movement. After this you can get beautiful details.

How to continue welding after it has stopped?

Since it is impossible to weld a long seam with electric welding without stopping, you have to change the electrode or there were other reasons for the interruption, then at the site of the stop you get a small depression, called a crater. To resume operation, you must perform the following steps:

1. The arc should not ignite on the crater itself. It is necessary to retreat 12 mm from it. Then it is slowly moved towards the crater.

2.The crater itself is carefully welded using oscillatory movements.

3.After this, you can continue welding, maintaining the set mode. To obtain a reliable connection, welding must have several layers:

• Workpiece, 6 mm thick – 2 layers;
• With a thickness of 6–12 mm – 3 layers;
• If the metal thickness exceeds 12 mm - 4 layers.

The movement of the electrode in each layer should be the same. The welding seam, after completion of the operation, is processed, removing all excess.

How are vertical seams made?

Figure 69a shows vertical welding. Since welding a vertical seam using electric welding is quite problematic due to the fact that drops of the melt tend to fall, it is necessary to weld such seams using a short arc. Surface tension prevents drops from immediately rolling down. They fall into the crater faster.

The tip of the electrode is removed from the drop so that it becomes solid. Vertical welding should begin from the bottom, gradually moving upward. The underlying crater will prevent drops of metal from falling. See Figure 69c. During operation, you can tilt the electrode. When it is tilted down, the welder sees how the drops are distributed at the place where the seam is being cut.

When it is necessary to perform vertical welding, start from the top point, the electrode must be installed in position I. See Figure 69d.

When the drops begin to fall, the electrode is set to position II. The drop will not drain; the short arc will not allow it.

The most suitable electrode diameter for vertical welding is considered to be 3 – 4 mm. The current should not be very high, approximately 160 amperes.

To achieve minimal melt drainage when horizontal seams are welded (see Figure 70, a), the edges are beveled at one upper part.

The arc should be excited at the lower end (position I). Then the arc is transferred to the end of the upper part (position II). The flowing drop begins to rise.

How the end of the electrode should move when single-layer horizontal welding is performed can be seen in Figure 70a, on the right side.

Horizontal seams are allowed to be welded in the form of longitudinal ridges. The very first one should be cooked with a 4 mm electrode, and all the rest with a diameter of 5 mm.

These are the main nuances that will allow you to correctly weld a vertical seam using electric welding.

How to electric weld a ceiling seam

Frequently asked question: how to weld a ceiling seam using electric welding, because it drains? The answer is simple: such seams are welded with a short arc. The welding electrode must have a refractory coating. When the welding process occurs, a cap appears at the end, which does not allow drops of metal to roll down. (See Figure 70, b). During operation, the end of the electrode is evenly removed and then brought closer to the part to be welded. When removed, the arc immediately goes out and the seam begins to harden. To perform ceiling welding, regardless of direction, use only electrodes of small diameters. The current strength decreases (10-12%) when compared to welding of metal of similar thickness produced below.

When ceiling seams are welded, gas bubbles begin to float up. They end up at the very root of the seam. This affects the strength and quality of the welded joint.

The use of ceiling welding is limited. It is remembered when it is impossible to get a seam from the lower position.

How fillet welds are welded

The molten metal during this welding will flow down. In the best way welding such seams from the lower position is considered “in a boat”. The part is installed in such a way that slag does not leak directly in front of the arc. (See Figure 68, a).

When a fillet weld is welded, with the bottom plane positioned horizontally, sometimes the corner vertices are poorly welded.

The reason for the formation of such a lack of penetration may be the start of the welding process from a sheet standing vertically. The molten metal begins to flow down onto the sheet, which has not had time to warm up well. That is why such seams need to be welded from the bottom plane. Moreover, the arc must ignite at a certain point (A). The movement must be carried out according to the diagram in Figure 68 b.

The electrode is tilted at 45 degrees in relation to the parts being welded. During welding, you need to tilt the electrode slightly different sides. (See Figure 68 c).

If fillet welds are not welded “in a boat”, the welding is done in a single layer, with a weld leg less than 8 mm. If the size of the leg exceeds this value, several layers are performed.

To weld multiple layers of a fillet weld, you must first create a narrow bead. To do this, use a 3-4 mm electrode. This diameter allows the root to be completely boiled.

To determine the number of passes, take into account the size of the cross-sectional area of ​​the existing seam. Typically this value is 30-40 square meters. millimeters. Figure 68 g clearly shows how fillet welds with different numbers of layers, having grooved edges, and fully welded should look like.

How butt seams are welded

If the edges are not beveled, the bead applied should have a slight flare on each side of the joint. To prevent lack of penetration, it is necessary to create a uniform distribution of molten metal.

Only the correct setting of the current and the competent selection of electrodes will allow 6 mm metal to be welded well if the parts do not have beveled edges. The current value is selected experimentally. Why are several test strips welded?

If the parts have V-shaped bevels, the butt weld can be a single layer or have multiple layers. Main role The thickness of the metal plays a role in this matter.

When one layer is welded, the arc should be excited at point “A”, at the bevel boundary, according to Figure 67a. After which the electrode is lowered down. The root of the seam is completely boiled, then the arc is sent to the next edge.

When the electrode moves along the bevels, its movement is specially slowed down to ensure good penetration. At the root of the seam, on the contrary, they speed up the movement to prevent a through burn.

On the reverse side of the welding joint, professionals advise applying an additional weld seam.

In some cases, a 2-3 mm steel lining is mounted on the opposite side of the seam. To do this, increase the welding current by about 20–30% relative to the standard value. In this case, through penetration is completely excluded.

When the weld bead is created, the steel backing is also welded. If it does not interfere with the design of the product, it is left. When welding very important structures, the opposite side of the root of the weld is welded.

If you need to weld a multilayer butt seam, the root of the seam is first welded. For this purpose, electrodes with a diameter of 4–5 millimeters are used. Then the next layers are surfaced with expanded beads, for which large-sized electrodes are used (See Figures 67, b, c).

Selection of welding electrodes

To choose the right electrode, you need to consider several important parameters:

• Workpiece thickness;
• Steel grade.

Depending on the type of electrode, the current value is selected. Welding can be done in a variety of positions. The lower one is divided into groups:

• Horizontal;
• Tavrovaya.

Welding vertical type May be:

• Bottom up;
• Ceiling;
• Tavrovaya,

Each manufacturer, in the instructions for the electrodes, must indicate the value of the welding current at which they will work normally. The table shows the classic parameters used by experienced welders.

The magnitude of the current is influenced by the spatial position, as well as the size of the gap. For example, to work with a 3 mm electrode, the current must reach 70–80 amperes. This current can be used to perform ceiling welding. This will be sufficient for welding parts when the gap size is much greater than the diameter of the electrode.

To cook from below, in the absence of a gap and the appropriate thickness of the metal, it is allowed to set the current strength to 120 amperes for an ordinary electrode.

To determine the current strength, 30–40 amperes are taken, which must correspond to one millimeter of the diameter of the electrode. In other words, for a 3 mm electrode you need to set the current to 90-120 amperes. If the diameter is 4 mm, the current will be 120–160 amperes. If vertical welding is performed, the current is reduced by 15%.

For 2 mm approximately 40 - 80 amperes are set. Such a “two” is always considered very capricious.

There is an opinion that if the diameter of the electrode is small, it means it is very easy to work with. However, this opinion is wrong. For example, to work with a “two” you need a certain skill. The electrode burns quickly and begins to get very hot when the current is set to high. With such a “deuce” you can weld thin metals at low current, but experience and great patience are required.

Electrode 3 - 3.2 mm. Current strength is 70–80 Amperes. Welding should be carried out using direct current only. Experienced welders believe that above 80 amperes, it is impossible to perform normal welding. This value is suitable for cutting metal.

Welding should start at 70 Amps. If you see that it is impossible to weld the part, add another 5-10 Amps. If there is a lack of penetration of 80 amperes, you can install 120 amperes.

For welding on alternating current, you can set the current strength to 110-130 amperes. In some cases, even 150 Amperes are installed. Such values ​​are typical for a transformer apparatus. When welding with an inverter, these values ​​are much lower.

Electrode 4 mm. Current strength 110-160 Ampere. In this case, the spread of 50 amperes depends on the thickness of the metal, as well as your work experience. “Four” also requires special skill. Professionals advise starting with 110 amperes, gradually increasing the current.

Electrode 5 millimeters or more. Such products are considered professional and are used only by professionals. They are mainly used for surfacing metal. They practically do not participate in the welding process.

Why are electrodes calcined?

This is done for only one purpose, to remove moisture. When welding with a raw electrode, welding seam defects may occur. Such an electrode will stick to the part all the time.

In each construction company Equipment that pierces the electrodes must be installed. This operation is not available to amateur welders.

If you started working with a new pack, but were unable to use it up completely, the remaining number of electrodes should be hidden in a dry and warm place. Never store electrodes in the basement or attic. They will quickly become damp and become unusable.

Conclusion

The rules of welding are quite simple, you just need to practice a few times on an unnecessary piece of iron. The main thing is to follow all the instructions given and you will definitely succeed. You can arc weld on both the ceiling and the wall.

There are an incredible number of moments when you need to weld by welding, and this may be required at home, in a country house, in an apartment, in a garage, in any high-rise building, in particular in such areas as construction or home repairs, as well as in plumbing, water supply and drainage installations and more. Hiring specialists to carry out welding work is not a cheap pleasure, and therefore many people prefer to weld the necessary elements themselves. How to do it right? Learning to work with electric welding from scratch is not easy, but it is quite possible, and for this you can attend lessons for beginners, purchase a tutorial for dummies, or use the tips presented below.

To weld metal sheets or pipes, you will need to familiarize yourself with safety precautions, study the work process, carefully follow the technology, or hire a welder such as a trumpeter.

Many people think that it is enough to learn how to use electrodes and how to weld seams, but you need to know all the intricacies of the work, especially regarding connection 2 different metals and what electrodes are needed.

Theory is one thing, but it takes a course of practice to start welding yourself various designs without mistakes and the possibility of leaks. For example, before welding, each element must be fixed using ties, clamps and other elements.

Need to know:

• What problems may arise;
• How to avoid defects;
• What is the welding technology for a specific type of element?

In addition, tack welds or, in other words, transverse seams, each of which holds the joints together, may be required, and it is advisable to install them at a distance of 10 cm from each other.

Welding seam options

There are different types of seams, which may differ from each other due to various factors, in particular in how the metal products are joined. These are the very basics of welding that are taught to beginners.

The seam can be:

• Butt;
• Overlap;
• Tavrovy.

The profession of an electric welder is very complex and sometimes requires too much investment in strength and energy, since welding of metal products can be carried out even under the ceiling. The classification of seams can be based on where they are located in space, and there are vertical, horizontal, and ceiling types.

Tips: how to learn to weld by yourself

It is quite possible to weld a metal structure yourself in 1 day if you know how many electrodes are required, which ones should be used, and provided that the product is not too large.

What else do you need to keep in mind to learn how to cook on your own:

1. For a welder, it is important not only to work correctly, but also to learn the basics, in particular what operating mode is required for a particular material, since the metal can be made of steel, alloys or fabrics such as metal.
2. You should definitely study the methods by which you can make a specific seam.
3. You need to choose the right electrodes and welding wire.

If you initially do not need to become a professional of the highest category, then you can learn welding yourself by watching video tutorials, drawings with seams, and also studying the advice of professionals. The training will be long, but possibly productive, especially if you gradually try to produce seams, increasing the amount of work experience.

To start welding, you need electrodes and the welding machine itself.

Many people prefer to use resanta, as the equipment can withstand long-term loads, which allows you to quickly complete the job. When first trying to work with welding, it is better to actually use an inverter, and only then when great experience Possibly with any other device. As for the electrodes, it is advisable to choose “3”. They are easy to use, and most importantly, they do not overload the electricity network.

In general, welding equipment is divided into types - transformer, rectifier, inverter. Why do inverters remain popular? They are compact in size, light in weight, and very easy for a beginner to handle. When taking the first steps to learning welding, it is worth taking simpler types of metal and preferably even elements, so as not to complicate the task.

Before welding you need to prepare:

• Bucket of water;
• Hammer for knocking down slag;
• Iron brush;
• A mask that protects the face and neck area;
• Gloves made of special fabric impregnated with a composition to prevent fire and burning of the fabric;
• Special clothing with long sleeves.

Do not forget that welding is a fire hazard, and therefore it is strictly forbidden to have combustible or flammable objects nearby in order to avoid serious consequences.

What defects are worth knowing about in order to make the correct welding seam?

Making beautiful seams that look perfect is not so easy, since even a specialist with extensive experience cannot always carry out the process as competently as possible. Everything depends not only on whether the rules are followed and whether the angle of inclination of the electrode is chosen correctly, but also on many other factors.

It is worth noting that any training manual contains data on defects, which you must familiarize yourself with.

There are critical ones, and there are non-critical ones, that is, those that can be left without additional processing. We learn how to distinguish a high-quality seam from a low-quality one and why defects occur.

Defects:

1. Lack of penetration is a defect in which the joint space is insufficiently filled liquid metal, this affects the strength of the connection. The reason may be low voltage or too high a speed at which the electrode moves. After the current has been adjusted and the arc has been shortened in length, the defect should be eliminated.
2. Undercut This defect indicates the presence of a groove running along the seam. The reason may again be too long an arc, due to which the seam is not just bad, but wide. This leads to incomplete heating of the metal, due to which the edges begin to quickly harden. To fix the problem, it is worth reducing the arc length and increasing the current.
3. Burns are through holes at the joints. The reason is a high current if the electrode is moved slowly, and too large gaps between the ends of the parts. The defect can be eliminated by correcting the welding mode.
4. If pores form on the seam, randomly scattered along the entire length of the joint, this is due to the presence of a draft in the room, due to which the gas cloud is blown away from the work area, or if the metal is covered with rust.

There are other defects in the form of cracks, or the seam simply bursts; this occurs immediately after the metal has cooled. They can be longitudinal and transverse. Depending on when they formed, they can be cold or hot.

Precautions before welding with electrodes

Regardless of where do-it-yourself manual electric arc camping welding is used, safety precautions must be observed, which is reflected in every welding textbook.

Precautions:

1. It is strictly forbidden to use arc welding in cold weather or in rooms with high humidity.
2. A mask and protective shield must be present to protect your eyes from burns.
3. Clothes must be specially impregnated to prevent sparks and drops of hot metal from rolling off.

Hands should be covered with suede gloves or special canvas mittens. Due to the fact that welding work is carried out at high temperatures, and the likelihood of fire is very high, the process should be carried out where there is water or a fire extinguisher nearby.

Nuances for beginners in welding

There are many tips on welding and even each master has his own secrets, but there are a number of general instructions, guided by which, you can carry out work and lay seams at an almost professional level, even with self-study.

Nuances:

1. You definitely need to remember about grounding, namely, there is a special clamp that needs to be tightly applied to the part.
2. Be sure to check the cable insulation and how carefully it is tucked into the part.
3. As soon as the ground is connected, the current strength is selected, it depends on the type of electrodes and the material.
4. Before lighting the arc, you need to install the electrode relative to the material at an angle of 60ᵒ.

The principle of welding and the work flow diagram are not too complicated. Namely, if you start moving the electrode slowly over the metal, sparks will begin to form, which indicates the formation of a welding arc. For this to occur, the electrode must be held so that the space between it and the canvas is 5 mm.

During work, the electrode will burn out, but there is no need to rush to move it.

The speed at which the seam needs to be applied depends on whether it should be thin or thick. If the electrode gets stuck, simply move it away or tilt it to the side. The technique is simple but effective. It is worth noting that there is such a term as a weld pool, and it can have different sizes. For example, width 8-15 mm, length 10-30 mm, depth 6 mm.

The format depends on:

• Location – indoors or in space;
• Welding mode;
• Configurations of each connected part;
• Edge size and shape;
• Arc movement speeds.

Welding techniques can be used to make a heating boiler or to connect water pipes. There are simply many places where welding equipment can be used, as it is used to erect fences, make playgrounds, assemble metal structures of high-rise buildings, install drainage systems, install railings and more.

Having not only the skills to work with welding equipment, but also the appropriate education, you can equip your home or site with all the necessary facilities, as well as get a prestigious job. Naturally, those welders who have a complete understanding of their work, welding modes, features and nuances of this matter are held in high esteem.

How to cook using electric welding (video lessons)

It is very easy to distinguish a beginner from a professional, since he will not be too hasty and will have to digest the seams more than once. If high-quality welding work is required, but there is not enough experience or knowledge, then it is better to entrust the process to professionals who can carry out everything at the highest level and at the same time provide a quality guarantee.

Examples of welding seams (photo)

Almost every person has encountered a situation where it was necessary to weld some metal part. Most often this happens during construction work. It’s great if a man knows this process, but sometimes you have to turn to professionals in your field. But you can learn welding on your own. Beginners usually start by learning seams. Complex work should be started only when the home craftsman learns how to properly weld using electrodes.

Basic Concepts

Welding today is the most reliable metal connection, because it fuses materials into one whole. The procedure is carried out under the influence high temperatures. Most welding machines use an electric arc to operate.

The principle of its operation is as follows: It heats the metal in a certain small zone to the melting point. This type of welding is called electric arc welding.

When forming an electric arc, both direct and alternating current can be used. For alternating voltage, transformers are used, for constant voltage, inverters are used.

The work is easier with inverters, since they operate on a 220 V network. They are small in size and weight, about 4-8 kg. They make almost no noise and do not affect voltage.

It is much more difficult to work with transformers, since the current is alternating, it affects voltage surges, which neighbors and household appliances are usually not very happy about. The device is large and heavy.

Thus it becomes obvious that For beginners, a welding inverter is more suitable.

Required Tools

For welding work you need a set of tools and special protection. This is the welding machine itself, electrodes, hammer and brush. The diameter of the electrodes depends on the material to be worked on.

Don't forget about protection. To protect your eyes, a welding mask is a must, and you should also wear thick clothing, suede gloves, and durable shoes. Devices that convert alternating current into direct current are also useful - this is a rectifier, inverter or transformer.

Work technology

For an electric arc to occur, conductive elements are needed: in this case, it is metal and an electrode. When metal and electrode come into contact, an electric arc appears. In the same place, the metal immediately begins to melt, and at the same time the electrode melts and is transferred to the weld pool.

Also in the process, the protective surface of the electrode burns, partially evaporating and releasing a certain amount of gases. These gases create a curtain and protect the metal from oxidation. The metal is also coated with slag, which helps the metal by maintaining its temperature.

The formation of a seam occurs when the electrode moves, which is the whole secret of welding. More it is necessary to monitor the angle of inclination and current parameters. After the metal cools, a slag crust remains on it, which protects the metal from oxidation. The slag is then beaten off using a hammer.

How to learn to cook

At first, welding work must be carried out under the supervision of an experienced welder; he will show you how to learn how to weld, give advice and help in case of problems. You can practice on a piece of metal.

For beginner welders 3 mm electrode is most suitable. It costs a little more, but is easier to work with. Later, as experience is gained, you can move on to other options. You can fix it in a special holder, which can be spring or screw and is attached to one of the cables. After fixing the electrode, you can begin connecting the cables.

On a welding machine there are two outputs: positive and negative. There are also two cables, one of them ends with a holder into which the electrode is inserted, the other with a special clamp.

In conventional types of welding, straight polarity is connected: minus goes to the electrode, plus to the part. But in some work, reverse polarity is used.

Electric welding process

After preparing all the parts and devices, you can start working. First of all, attach the cable with the clamp. Then you need to check the other cable for insulation and reliable fixation of the electrode. Then the current power is set on the welding machine depending on the diameter of the selected electrode.

An electric arc is ignited. To do this you need to slightly touch the metal with an electrode, sparks should fly out. After the first contact, the electrode touches the metal and rises to a height of 5 mm.

The height of 5 mm must be maintained throughout the entire operation. As the process progresses, the electrode should burn out and it will need to be changed. It can also periodically stick to the metal, in which case you need to shake it slightly.

After igniting the arc, you can proceed to fusing the bead. This is done with light oscillatory movements, smoothly moving the electrode. The result of the operation should be a seam with a slight deposit of metal.

Electrode movement can occur in three directions:

• Progressive.
• Transverse.
• Longitudinal.

As you work, you can superimpose one option onto another. Each master prefers to work in his own direction. After all, the main task is to reliably connect metals, and how this happens is not so important.

Some nuances

It is not enough to simply move an electrode across metal. You need to know some of the nuances of welding and how to properly weld a certain metal. One of them is that the seam “pulls” the part, which can cause them to lead. And in the end the result will be completely different from what the master expected. Most often, this problem can be avoided by grabbing the part in several places, approximately every 10 cm. This is done on both sides, after which the main work begins.

How to choose the right current

In addition to bonding the metal before welding, you need to know what current value to set in certain situations. It all depends on the thickness of the metal being worked on and the diameter of the electrode.

But sometimes the voltage may suddenly drop, the inverter itself will not be able to react to this situation. In this case, you just need to slow down the movement of the electrode to warm it up. Repeatedly running the electrode along the seams may also help. If this doesn't help, you can install a smaller diameter electrode.

Pipeline welding

Using electric arc welding, you can make a horizontal seam that runs around the circumference of the pipe and a vertical seam that runs from the side, as well as top and bottom seams. The most convenient option is the bottom seam.

Steel pipes must be butt welded, welding all the edges along the height of the walls. During operation, the electrode must be installed at an angle of 45 degrees - this is done in order to reduce sagging inside the products. The seam width should be 2−3 mm, height - 6−8 mm. If welding is overlapped, then the required width is 6-8 mm, and the height is 3 mm.

Immediately before starting work preparatory procedures need to be carried out:

• The part needs to be cleaned.
• If the edges of the pipe are deformed, then straighten them or cut them off with an angle grinder, or simply with a grinder.
• The edges where the seam will go must be cleaned to a shine.

After preparation, you can start working. Necessary weld all joints continuously, completely welding. Pipe joints with a width of up to 6 mm are welded in 2 layers, with a width of 6-12 mm in 3 layers and with a wall width of more than 19 mm in 4 layers. Main feature consists in constantly cleaning the pipes from slag, i.e. after each completed layer it is necessary to clean it of slag and only then weld a new one. Particular care must be taken when working on the first seam, it is necessary to fuse all blunts and edges. The first layer is carefully checked for the presence of cracks; if they are present, they must be melted or cut out and welded again.

All subsequent layers are welded while slowly turning the pipe. The last layer is welded with an even transition to the base metal.

Mistakes of novice welders

To find out how to properly cook with electric welding, you need to consider the main mistakes that beginners make:

All of the above mistakes are just the most serious ones. There are many more nuances that can only be understood with experience.

When welding thin-walled metal or profile requires a careful approach to work. Thin parts can be welded by applying a cleaned electrode and welding directly on top of it.

Welding on non-ferrous metals is strikingly different, as it requires different electrodes. A special protective environment is also required. Now you can buy universal machines that cook almost any metal.

There are also semi-automatic devices for working with thin-walled metals. Its essence lies in fusing a special wire.

Electric welding for beginners is not an easy task. But if you have enough desire, you can master it. You just need to follow the basic rules and listen to the advice of more experienced masters. As a result, you will be able to move on to complex tasks, honing your skills.

Mastering the technique of obtaining a strong weld is an excellent skill that brings a lot of benefits to the real owner. A well-studied process can be so fascinating that after making a simple frame for a greenhouse, a stove for a garage or a tank for a country house, you will want to create something complex and original such as an openwork fence, a bench, or a barbecue. But before implementing plans, it is necessary to find out all the questions about how to learn how to weld with electric welding, familiarize yourself with the information and educational video. Having mastered the basics, you can safely begin creating unique metal masterpieces.

It is unlikely that other types of connections of metal parts can compete with the strength of welded seams if their joining must be permanent. Heating of metal alloys with an electric arc causes plastic deformation of the materials. As a result of the mutual penetration of the electrode particles and the elements being connected, ultra-strong intermolecular bonds are formed.

Electric welding is the key to the strength of the connection of metal parts

The introduction of advanced technologies now makes it possible to weld using laser and electronic radiation; metals are welded with ultrasound and gas flame. Most often, the energy source is an electric arc created by an inverter or welding machine. It’s worth starting your training with the simplest and most common welding methods.

Preparation for practical classes

Welding skills are learned mainly through practice. Therefore, it is necessary to know what a novice welder who has received theoretical information and wants to apply the knowledge needs to stock up on.

Attention. Welding is associated with the risk of burns from splashes of molten metals, poisoning by toxic secretions, and the possibility of electric shock. The radiation can cause burns to the cornea of ​​the eyes. Prepare thoroughly without skimping on gear and equipment.

The work of a welder is associated with the risk of injury, gas poisoning, and burns.

Choosing the right equipment

For practical exercises, you can make a welding unit yourself. But if there is no practice in this matter, it is advisable to rent or buy welding equipment with a device for continuously adjusting the current strength, the maximum value of which is about 160 A. The following will help you learn the skill of a welder:

• Welding transformer that converts alternating current supplied by the network into alternating current for the welding process. An easy-to-maintain, productive, cheap unit has disadvantages: it does not provide high arc stability, “squanders” voltage, and is excessively heavy.
• Welding rectifier, the operation of which is based on obtaining direct welding current by converting alternating current from the network. In terms of the set of disadvantages and advantages, the unit is similar to the previous version, but it better maintains arc stability, which improves the quality of welding seams.
• Welding inverter, supplying direct current and voltage obtained as a result of alternating current conversion for welding. This is a lightweight compact device with smooth adjustment of current parameters, fast-acting and productive equipment with easy ignition.

The choice of welding equipment should be made based on the needs

Experienced welders advise buying an inverter. It won’t take up much space and will be a better help in learning. Watch a video about how to choose a machine, how to prepare and how to learn how to weld with electric welding - the video will help you visualize the beginning practical course.

How are the electrodes different?

Arc welding is performed using consumable electrodes. Their function is to supply current to the seam. The main component of automatic or semi-automatic welding can be flux-cored wire, mechanically supplied to the melting zone as it is used. However, most training courses recommend starting with electrodes, which come in the form of solid rods with a special melting coating. With them you can quickly “get” your hand and gain skills in forming clear, even deposited lines.

Welding electrodes in the form of metal rods are the best choice for beginners

Rod electrodes with a diameter of 3 mm are considered optimal for beginners. To work with thicker electrodes, powerful equipment will be required. Rods with a cross section of 2 mm are used for welding parts made of thin sheet metal. You should not use old arc welding components that someone has lying around, and if they are also damp, there will be no use at all.

Welder equipment - ensuring safety

A future welder definitely needs a protective shield or welder's mask. They will protect your eyes from burns caused by exposure to bright radiation, and your facial skin from hot metal splashes.

For practical exercises you will need a protective shield or welder's mask.

The skin of your hands also needs to be protected from scalding splashes of molten metal. You need canvas work mittens or suede gloves (knitted or cotton gloves will not work).

A suit or robe with pants should be made of dense material, preferably thick, high-density tarpaulin.

Important. Near the place of work you need to place a bucket filled with water, stock up on an old thick blanket to be able to extinguish a fire from an accidental spark.

For practical exercises, it is preferable, but not necessary, to be located outside. All flammable objects in the work area and likely reach of a spark must be removed.

The first steps of a future good welder

Initially, each student of the skill makes rollers on unnecessary pieces of metal, simply melting the material without creating connecting seams. The surface must be cleaned of rust and dirt.

Beginning of practical classes: how to make rollers

• The electrode is inserted into the holder of the welding machine.
• You can initiate the supply of current to the melting zone by striking the metal with the end of the rod, like a match, or touching the workpiece with tapping movements.
• After creating an electric arc, the electrode must be directed towards the workpiece. The gap between the electric arc and the metal must be constant, not less than 3, but not more than 5 mm.

Please note. The quality of the future seam depends on the ability to maintain a constant gap. If the distance changes, the arc will be interrupted and the seam will be defective.

• The rod is held at an angle to the plane of the workpiece. A tilt of 70º is considered convenient, and the electrode can be tilted forward or backward, as is more convenient for the performer. In the future, the size of the inclination can be changed depending on the preferences of the welder and the specifics of the operation being performed.

At this stage of practical training, it is necessary to learn how to select the current strength for its stable supply. If there is insufficient current, the arc will go out; too powerful a flow will melt the metal. The skills of setting the welding mode can only be obtained through experimentation.

Learning to make welded joints

After making sure that the rollers come out smooth and almost beautiful, you can practice making connecting seams. These are already actions for the confident hand of an almost experienced trainee who knows how to properly learn how to weld with electric welding and implements the information received.

Second step of training: simulating a weld on a workpiece

All initial steps to ignite the electrode are similar to the processes described above. Only the hand of the welder connecting the parts does not move in a straight line, but makes oscillatory movements, as if redistributing the molten metal of one part to the neighboring element and vice versa. The trajectory of movement can be zigzag, loop-shaped, or resemble a series of Christmas trees or sickles.

Several types of seams made by electric arc welding

You need to practice again on a piece of unnecessary metal, drawing a line on it with chalk, visible through the darkening glass of the mask. Along it you need to lay a kind of seam, drawing a continuous narrow strip along one of the above trajectories.

You need to beat off the slag from the cooled seam with a hammer, after which the welder’s work will appear before your eyes.

The slag from the cooled seam must be knocked off with a small hammer.

After obtaining the first skills, you can begin to produce connecting seams. They can be T-shaped, butt, corner, overlapping, made horizontally or vertically from bottom to top and in the opposite direction. In order for your hand to move confidently, you need to practice a lot and only then start making useful, beautiful homemade items.

Types of welded joints and their appearance

Video guide for beginners

Skills in working with a welding machine will help you make a lot of useful metal structures for a summer house, garage, bathhouse, and storage facility. Surely after the first steps you will want to do something amazing. Just to master all the nuances of the skill, you need to work hard to gain dexterity. And, of course, for more complex welding techniques, more in-depth information such as professional manuals with descriptions of complex processes and a list of technical regulations will be required.