How to make a weld. How to cook with electric welding? How to weld a vertical seam with electric welding

Quite often, it is required to connect metal parts or fragments of parts. There are several ways to get the desired result. Most often, the method of electric welding is used to connect iron and steel parts.

What is it based on?

How to cook with electric welding? In order to understand the principle, you need to remember the physics from the school curriculum. One of them is connected to the working part. When the electrode comes into contact with this surface, a depression forms at the point of contact, which is filled with molten metal as the electrode moves. The edges of the metal parts melt under the influence of enormous temperature and turn into a single whole.

Arc ignition methods

When learning how to weld metal with electric welding, it is worth learning a few things about the method itself. The distance and electrical high-temperature pulse between the workpiece and the electrode is called an arc. There are two ways to create such conditions:

In the first case, the electrode (quickly touching) is “strike” over the iron, as if with a match. The resulting arc must be maintained by conducting an additive a few mm from the working surface of the metal.
In the second case, the tip of the electrode must be sharply tapped on the workpiece.

The resulting arc should not go out. If this does happen, before the electric welding continues, the seams must be cleaned of scale. Neglect of this rule leads to the formation of a hole.

Importance of amperage for welding

The calculation of the current strength corresponding to the thickness of the electrode will show in practice how to learn how to cook with electric welding. With insufficient current, the electrode will stick, and the arc will go out. With a large current, the metal will splatter and burn. If you use a welding transformer, then an electrode of 1 mm corresponds to a current of 30-35 A. When using an electrode of 3 mm, a current of 80 A corresponds. If you increase the current, iron can be cut.

The electrodes are selected taking into account the chemical composition of the metal. There are several types of this filler material:

steel;
bimetallic;
cast iron;
copper;
brass.

All of them are marked with an index and numbers indicating what metal of what hardness and thickness each type is intended for.

When learning how to properly weld by electric welding, you need to remember that in order to obtain high-quality seams, the electrodes must match the thickness of the metal.

Welding of flat sheets of metal

Thin metal (from 1 to 3 mm) is joined end-to-end without gaps and additives, achieving a good match of aligned edges.

For a better fit of the joints of thicker sheets (from 3 to 8 mm), the edges should be cut at right angles. Between the sheets leave a gap of up to 2 mm. Material 8 mm thick is connected by double-sided welding. To connect thicker planes, the edges are cut with a bevel.

How to start learning to cook iron

Learning how to cook with electric welding starts with the simplest processes.

The prepared parts are fixed on a horizontal surface (on a welding table).
Tacks fasten them around the edges and in the center.
It is necessary to insert a new additive into the holder and attach a ground clamp to the part.
First, work out the correct tilt of the electrode (about 75 degrees) in the direction of the arc. In this case, it is necessary to make movements that, as it were, rake the molten metal into the junction.
The end of the electrode should be in the center of the seam. Due to the observance of the angle of inclination, the drops flow more evenly from the hot electrode and form an even, high-quality roller.
After cooling the workpiece, it is necessary to beat off the slag from the surface of the part.

Time after time, as you gain experience, the seams will turn out smoother and more accurate.

How to make a vertical seam

How to cook a vertical seam with electric welding? The main thing is to start by following all the recommendations. Welding vertical seams is similar to working horizontally, only a little more complicated. The blanks are picked up in two or three places. Then welding is carried out only from the bottom up, sticking drop by drop. Gradually, the entire gap is filled with hot metal. How to learn to cook with electric welding? The task is to merge both edges, melting them with a welding arc, while simultaneously directing metal drops there from the end of the electrode heated to a state of liquid.

You can weld the seam not with drops, but with the so-called "eight", but only an experienced specialist can handle this. So, if you are interested in knowing how to learn how to weld a vertical seam by electric welding, it is first recommended to look at the work of an experienced welder, listen to the advice of the masters. And only then independently start the process.

How to make a beautiful and strong corner seam

Correctly making the so-called "tee" seam is not as easy as learning how to cook with electric welding. This seam is used if you want to fasten parts at different angles. The metal parts are installed so that the welding flows into the very corner. The welded parts fixed by the “boat” are tacked from opposite sides. In addition, one edge of the workpiece rises slightly higher. The welding process must begin from the bottom edge. In this case, carefully following the instructions on how to properly weld by electric welding, the quality of the weld can be significantly improved.

Which one is better to use

The old ones with an adjustable magnetic gap that allows you to adjust the current strength are transformer ones. There are many variants and models that have rheostats and additional chokes on the primary or secondary sides of the transformers.
Inverter machines are more modern welding devices. Working from an increased frequency, the transformer of such units has smaller dimensions and low weight. In such devices, you can smoothly adjust the welding modes. The settings of the latter must be carried out carefully, otherwise the device can quickly fail.

Pipe welding methods

In the absence of experience, it is better to learn how to weld a pipe by electric welding on thick metal. Several passes are made depending on the wall thickness of the pipe. Multi-layer welding improves the mechanical properties of the resulting seam, the connection becomes stronger.

First, a half ring is welded in one direction, then in the second. With the method of conducting the seam "from top to bottom", 4-mm electrodes with organic sputtering are used. With a short arc, relying on the resulting "visor", the attachments are driven by small transverse vibrations.

When working according to the “bottom up” method, the speed is sharply reduced. Conducting transverse oscillations of the electrode is done in 3-5 mm.

When from pipes, you first need to prepare and lay out all the material on the welding table or stand. Then they are centered and tightened to obtain the gap required for welding. The assembled joints are tacked together.

Pipes with a small diameter are connected by continuous welding, with a large diameter - by an intermittent method. After completion of all welding processes, the working surface of the metal is cleaned of scale, frozen spatter, and slag. A control inspection is carried out to detect cracks or burns, outgoing craters or pores. In the presence of poorly welded places, the seam is restored.

For your own safety, you need to work while welding in suede gloves and mittens, in a welder's mask, in tarpaulin or thick leather boots and in a cotton robe. Be sure to have a fire extinguisher or a container of water nearby.

The ultimate goal of any welder is to obtain a quality weld. The strength and durability of the connection of parts depends on this. For successful operation, it is important to make the connection correctly; select the current strength, the angle of the electrode; have a good command of the seam technique. The result of proper operation will be reliable welding of metal parts.

Welds are classified according to several criteria. The types and types of welding joints must be considered sequentially, delving into the intricacies of the process. The seam is affected by the location, direction and trajectory of the electrode.

After fixing the selected electrode in the clamp, setting the current, connecting the polarity, the welding process begins.

Each master has his own preferred angle of inclination of the electrode. Many consider the optimal value of 70 ° from the horizontal surface.

From the vertical axis, an angle equal to 20 ° is formed. Some work at a maximum angle of 60°. In general, most training guidelines present a range of values from 30° to 60° from the vertical axis.

In certain situations, when welding in hard-to-reach places, it is necessary to orient the electrode strictly perpendicular to the surface of the material being welded.

You can also move the electrode in different ways, in opposite directions: away from you or towards you..

If the material requires deep heating, then the electrode is led to itself. Behind him, in the direction of the welder, the working area stretches. The resulting slag covers the place of the alloy.

If the work does not involve strong heating, then the electrode is moved away from itself. Behind him "creeps" the welding zone. The depth of heating with this design of the seam is minimal. The direction is clear.

Trajectory

The trajectory of the electrode movement has a special effect on the seam. In any case, it has an oscillatory character. Otherwise, the two surfaces cannot be stitched together.

Oscillations can be similar to zigzags with different steps between the sharp corners of the trajectory. They can be smooth, reminiscent of moving in a displaced figure eight. The trajectory can be like a herringbone or a capital letter Z with monograms at the top and bottom.

An ideal seam has a constant height, width, uniform appearance without defects in the form of craters, undercuts, pores, lack of penetration. The name of the possible flaws speaks for itself. Having worked out the skills well, you can successfully apply any seam, weld a variety of metal parts.

Standards and the concept of the leg

The weld begins to form in the working area in the molten state of the metals, and is finally formed after solidification.

The existing classification groups seams according to various criteria: the type of connection of parts, the resulting shape of the seam, its length, the number of layers, orientation in space.

The types of possible welded joints are displayed in the GOST 5264 standard for manual and arc welding. The joints performed by arc welding in a shielding gas atmosphere are standardized by the GOST 14771 document.

GOSTs have a designation for each welded joint, as well as a table containing the main characteristics, in particular, the values of the leg of the weld.

What is a leg, it is quite simple to understand by looking at the drawing of the parts to be joined. This is the side of a speculative isosceles triangle of maximum dimensions that will fit in the cross section of the seam. A correctly calculated value of the leg guarantees the strength of the connection.

For parts of uneven thickness, the cross-sectional area of \u200b\u200bthe part in its thinnest part is taken as the basis. You should not try to unreasonably increase the leg. This can lead to deformation of the welded structure. In addition, the consumption of materials will increase.

Checking the dimensions of the leg is carried out using the universal reference templates presented in the specialized literature.

Connection types

Depending on the relative position of the parts, welding joints occur:

butt;
overlap;
angular way;
in a tavern way.

When butt welding, the ends of two parts located in the same plane are welded. The joint can be made with flanging, without bevel and with bevel. The shape of the bevel may resemble the letters X, K, V.

In some cases, welding is done with an overlap, then one part is partially hoisted onto another, located in parallel. The combined part is an overlap. Welding is done without a bevel on both sides.

Often there is a need to make a welded corner. Such a connection is referred to as an angular type. It is always performed on both sides, may not have bevels or have a bevel on one edge.

If the welded parts formed the letter T as a result, then a tee connection was made. Sometimes parts welded with a tee seam form an acute angle.

In any case, one part is welded to the side of the other. Welding is carried out on both sides without a bevel or with bevels on each side.

Shape and length

The shape of the seam can be convex, even (flat). Sometimes it becomes necessary to make a concave shape. Convex connections are designed for heavy loads.

The concave places of the alloys withstand dynamic loads well. Versatility is characterized by flat seams, which are made most often.

Along the length, the seams are continuous, having no intervals between the fused joints. Sometimes intermittent stitches are enough.

An interesting industrial variation of the intermittent weld is the joint that is formed by resistance seam welding. They do it on special equipment equipped with disk rotating electrodes.

Often they are called rollers, and this type of welding is called roller welding. Solid connections can also be made on such equipment. The resulting seam is very strong, absolutely tight. The method is used on an industrial scale for the manufacture of pipes, containers, hermetic modules.

Layers and location in space

A metal seam may consist of a bead made in one pass. In this case, it is called single layer. With a large thickness of the parts to be welded, several passes are performed, as a result of which rollers are sequentially formed one on top of the other. Such a welding joint is called multilayer.

Given the variety of production situations in which welding takes place, it is clear that the seams are oriented differently in each case. There are bottom, top (ceiling), vertical and horizontal seams.

Vertical seams are usually welded from the bottom to the top. The trajectory of the electrode movement along the crescent, herringbone or zigzag is used. It is more convenient for novice welders to move with a crescent.

When welding horizontally, several passes are made from the lower edge of the parts to be joined to the upper edge.

In the lower position, butt welding or in any angular way is carried out. A good result is obtained by welding at an angle of 45 °, "into the boat", which can be symmetrical and asymmetrical. When welding in hard-to-reach places, it is better to use an asymmetrical “boat”.

The most difficult thing is to weld in the ceiling position. This requires experience. The problem is that the melt is trying to drain from the working area. To prevent this from happening, welding is carried out with a short arc, the current strength is reduced by 15-20% compared to the usual values.

If the thickness of the metal at the welding site exceeds 8 mm, then several passes must be performed. The diameter of the first pass should be 4 mm, subsequent - 5 mm.

Depending on the orientation of the seam, select the appropriate position of the electrode. To perform horizontal, vertical, ceiling connections, welding fixed joints of pipes, the electrode is directed at an angle forward.

When welding corner and butt joints, the electrode is directed at an angle backwards. Hard-to-reach places are boiled with an electrode at a right angle.

Processing of a welded joint

During welding, slags are formed. If slag inclusions get into the seam, its quality deteriorates. All slag layers must be cleaned.

If welding is performed in several passes, then the seam cleaning is performed after each welding stage. In this case, any methods are used. First, the welded parts are beaten with a hammer and cleaned with a stiff brush.

Then carry out a rough cleaning. Small parts are cleaned with special knives or grinding wheels. Large blanks are cleaned on machines. At the final stage, the place of the welded joint is polished.

Often, a fiber wheel grinder is used for this. There are other ways to polish welded joints.

Welding is constantly evolving. New materials appear, technology improves. It is necessary to follow the news in the welding business in order to learn a lot of new and interesting things.

Welding is one of the main methods of fastening two elements, and welds are zones connecting two metal blanks to each other. Such adhesions are obtained during the melting and subsequent cooling of the steel.

A good welder must know the types of welds and be able to apply all types of seams. . Without these skills, it is impossible to produce a high-quality and durable design.

Joint types

Welds are divided into 5 variations:

lap;
parallel;
butt;
corner;
t - figurative.

Lap laps are often used to create cylindrical tanks that are planned to be operated in a horizontal or vertical position. Welded elements overlap, but do not completely overlap. The result is a structure that looks like a step. Welded seams are applied from the end sides of the parts .

Parallel application methods are used to increase the strength of the structure. Both components are tightly applied to each other and fastened by welding from the side of the ribs. With this technique, it is possible to strengthen structures, the appearance of which will have a strong mechanical effect. However, this technology is forbidden to be used in the repair of moving mechanisms.

The butt version is the most popular. The parts to be welded must be in the same plane, one opposite the other. Such a joint is used to fasten water pipes, chimneys, storage facilities or steel columns. Also, this system is used in mechanical engineering, in the manufacture of air and water transport, in military plants. Yes, and the creation of such a "gluing" requires a minimum of money and time.

Fillet welds are well suited for joining multiple workpieces that need to be placed at right angles. The workpiece is made as follows: parts are installed at an angle of 90 ° (in the form of the symbol “G”), and a weld is applied at the junction of the edges . This welding is common both in industry and in the private sector. And with its help you can make strong supports or boilers.

A T-weld or tee weld is unlike any other, as the finished part will look like the letter "T". It will be difficult for an inexperienced person to create this, since it is important to take into account the restrictions related to holding the electrode in the process (it is recommended to adhere to an angle of 60 °). In this case, the thickness of the sheets to be joined may differ. Also, more wire will be required to complete, and elements welded by the T-weld method may come out with defects.

Work technique

The movement of the rod in a solid line will not be enough for a good weld. , and to become a master of your craft, you need to understand the technique of using the apparatus. The main features of the technology are constant control of the gap between the components. If the distance is too small, then the steel will not warm up well, which will negatively affect its strength. Both the speed of the tripod and the basic soldering procedure should be controlled. The main thing is that the molten metal is evenly distributed over the groove.

How to suture correctly :

Cook in circular or zigzag motions. The trajectory must be maintained throughout the soldering.
Hold the handle at the right angle. The sharper the slope, the shallower the steaming depth.
Control the rate of movement of the electrode. It all depends on the voltage of the device. High current allows you to move the holder at a faster speed, and the seams will be finer in the end.
Properly choose the layers of soldering. Several rows can be made in the butt places, however, a tee weld is more often made by this technique.

Taking into account these rules will help to achieve the desired result, and the specialist will accurately produce any type of welding seam.

Application methods

Application methods include:

Horizontal type. According to the rules, you can apply a seam both from right to left, and in the opposite direction. It is important to observe an acceptable angle of inclination here, since excess molten metal will flow out. If a person has few skills, then the entire procedure can be completed in 2-3 passes.
Vertical type. The working surface can be located in the ceiling or wall areas. Welding joints can also be made in two ways: from top to bottom, and from bottom to top. However, it is better to choose the first option, since the heat from the arc contributes to a high heating of the alloy.
Ceiling type. The whole process must be carried out very quickly, while maintaining a stable pace of the rod. Also, to keep the alloy in the seam, you will need to make rotational movements. It should be noted that the current variety is the most complex, and work should be started after gaining the necessary experience.

From the first time it is difficult to understand what varieties there are and to study all the technologies. But regular practice will make any beginner a true professional.

To date, the following types of electric arc welding are known:

At home, these types of welding are practically not used. Therefore, let's move on to the consideration of the fourth type of welding - manual arc welding.

Manual arc welding is based on the use of a special electrode in the coating

Electric welding machines for manual welding are divided into two types - AC and DC. The use of alternating current makes it possible to design devices of high performance and power. The advantage of direct current, due to the lack of polarity reversal, is a smoother seam with less metal spatter.

In 1802 V.V. Petrov discovered the phenomenon of a galvanic voltaic arc.

A device for welding metals with the help of "electrohephaestus" was patented in 1882 by Benardos N.N.

Russian engineer N.G. Slavyanov in 1888 was the first to use an electrode for welding.

In 1932, the Soviet physicist Khrenov K.K. successful welding of metals under water.

Subsea pipeline repair

The operation of the welding machine is based on the creation of an electric arc at the point of contact between two metal parts. High temperature (up to 7000 ° C) melts the material to a liquid state and diffusion occurs - mixing at the molecular level.

The fundamental difference between welding and gluing is the absence of auxiliary materials - the parts to be joined turn into a monolithic structure.

Therefore, it must be clearly understood that only homogeneous metals can be used for the correct application of welding. You can't weld aluminum to iron or copper to stainless steel. The melting point of different materials is different, and the creation of alloys is not included in the range of possibilities of welding equipment.

For welding iron structures, there are various welded machines.

The main advantage of inverter welding is the improvement in the dynamics of the electric arc, as well as a significant reduction in the weight and dimensions of the installation (compared to direct transformers). In addition, it became possible to smoothly adjust the output current, which significantly increased the efficiency of the unit and ensured the ease of ignition of the arc during operation.

But there are also disadvantages:

temporary restrictions in use, which is associated with heating of the electronic conversion circuit;
creation of electromagnetic "noise", high-frequency interference;
the negative influence of air humidity, which leads to the formation of condensate inside the device.

What is needed for work

Before you start welding, you need a welding machine and equipment:

The place of welding work is freed from combustible materials and equipped with fire extinguishing agents - water, sand, industrial soda. If this is a closed room, it is necessary to equip the supply and exhaust ventilation.

Essential fire fighting equipment for any facility

How to cook by welding

To successfully master the technique of permanent connection of metal parts, it is necessary to master 4 basic skills, without which not a single “welding session” can do.

Machine setup

The basis for setting up the welding machine is the correct selection of the current and voltage output to the terminals. Despite the simplicity of the wording, the topic of customization deserves a separate discussion. But if we briefly formulate the tuning criteria, then we can distinguish 5 main parameters:

In order to accurately select the current value, it is easiest to use ready-made tables.

But due to the fact that each device has its own design features and technological nuances, the decisive word still remains with the “scientific poking method” - an empirical selection of the required current experimentally.

Welding current setting depending on the electrode diameter

Correlation table of electrode and welding current

Current selection mode for welding standard butt joints:

A one-sided seam connects the surface of the parts on one side, a double-sided seam connects the surface of the parts on two opposite sides.

Examples of welding parts with various seams

You can also use the universal table for a wide range:

It is easy for a beginner welder to remember a simple rule. If the current exceeds the required value, the electrode will burn through the workpiece. If the current is lower than necessary, the part does not boil through, the deposited metal falls off when exposed to it mechanically.

Electrode connection

The electrode can be connected to the positive or negative current output. If “+” is connected to the part, then the polarity is called straight. If "-" - reverse. Accordingly, with direct polarity, a “minus” is located on the electrode, and with a reverse “plus”. The difference between these positions is that more heat is always generated at the "positive" terminal. Experienced welders use this phenomenon to solve specific problems. So, for example, by manipulating the polarity, it is possible to cook stainless steel sheets that are sensitive to overheating. To do this, "plus" is fed to the electrode, and "minus" - to a sheet of thin metal.

One of the options for connecting the electrode

Video: direct and reverse polarity when operating an inverter welding machine

Create an arc

The welding process begins with the ignition of an electric arc. In all types of manual welding, the arc is created by briefly touching the electrode to the workpiece. In this case, there is a sharp heating of the end of the electrode to a temperature sufficient to establish an arc discharge.

The process of ignition of the electrode arc requires certain skills

After a short circuit, if the arc has ignited, it is necessary to maintain a distance between the end of the electrode and the workpiece of 3–5 mm. In this case, it is necessary to take into account the fact that the length of the electrode decreases as welding progresses. When the distance exceeds 5 mm. the arc is interrupted when the reduction is less than 3 mm. the electrode may stick to the workpiece or cause large spatter of molten metal.

Electrode movement

To create a good seam, various schemes for conducting the arc along the welded place have been developed. In this case, it is important not only to melt the edges of the parts to be welded, but also to fill the weld pool with the necessary amount of metal deposited from the electrode.

Various options for the trajectory of the electrode end

This can be achieved while maintaining a constant length of the electric arc and systematically moving the end of the electrode along a certain trajectory.

In the production of a seam without transverse movements, the width of the joint, as a rule, is equal to b \u003d (0.8–1.5) xd el. Where b is the width of the welded joint, and d is the diameter of the electric

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Today, there are a lot of different ways of connecting metal products. They can be divided into two groups:

Detachable.
One-piece.

Classification of welds.

The connections of the first group include parts that can be separated without breaking the connecting elements, for example, a bolt with a nut. It is the second connection that is the most reliable. In this case, the parts cannot be separated without breaking the connecting part. We are talking about welding and riveting joints. When it is required to obtain a high-quality and reliable connection, the welding seam is considered the best. A lot of people buy welding machines to weld parts, but they have absolutely no experience. After several unsuccessful attempts, they have a question: how to put the welding seam correctly? To do this, you need to know a few basic rules.

Main characteristics

The welding process is a metal connection using electric arc welding. The parts to be joined are melted using an electric arc and an electrode consisting of a metal rod with a special coating. A lot of different factors influence the quality and reliability of a welded seam:

Scheme of welding with a coated metal electrode.

welding machine;
current adjustment;
electrode size;
professionalism of the welder.

Types of welding that are used in everyday life and industry are divided into several groups:

gas press;
contact;
roller;
electroslag;
thermite;
friction welding.

When gas pressure welding is used, an open flame of oxyacetate is used. The positive side of this method is considered to be high productivity. This method is widely used in the gas and oil industry. It often occurs when laying pipelines. This method is widely used in mechanical engineering.

Resistance welding occurs at a low voltage, but a high value of electric current. This method can be used for spot and butt welding.

Scheme of a semi-automatic welding machine.

To master the technological process of welding, first of all, you need to have the appropriate welding equipment. You can rent or buy it. Today, stores offer a wide range of welding machines, which have a device that makes it possible to adjust the current strength. A home master can make a welding machine himself, but he cannot do without an electrical energy converter. These devices come in several varieties.

Some types of devices for quality work

Transformer. Designed to receive direct current when you have to use a household outlet. When buying such a unit, you must always remember that inexpensive models are not able to maintain stable operation of the electric arc. Very often there is a "sag" voltage. The negative side is also their mass, they are heavy and clumsy.

Rectifier. This is a device that converts household current into direct current. The device differs from the transformer in the stable operation of the electric arc. The quality of the weld is quite high.

inverter. The latest converter that allows you to work on any type of current. Gives always high quality of welding. The seams are even and smooth. The device is very compact, light weight, easy to ignite. The inverter is high performance and fast.

For normal operation of electric welding, there must be a stable arc burning. Such constancy depends on the correct choice of the gap between the workpiece to be welded and the electrode coating. The arc burns best when the gap is 5 mm.

Technique for making welds.

The high temperature of the arc causes melting of the part and the metal rod of the electrode. At this time, all the recesses that were formed as a result of melting are filled. With the slow movement of the electrode along the surface of the seam, voids are filled.

In order to be proud of the resulting seam, it is necessary to choose the right electrode. To do this, you need to know the composition of the metal of the part that will need to be welded. The selection of the electrode is based precisely on these parameters. There are several types of electrodes. They can be:

steel;
copper;
cast iron;
bimetallic;
brass.

By marking the electrode, you can determine the viscosity of the resulting seam, the numbers will tell you about the hardness of the metal. The main rule when choosing an electrode is its size. It must match the thickness of the metal.

For high-quality electric welding, so that the seam looks neat and durable, it is necessary to correctly select the slope of the electrode. Typically, this angle is 75 degrees relative to the direction of the arc. In order for an arc to appear, you need to strike over the surface of the metal and, when a flash appears, quickly raise the electrode. When an arc appears, it must be slowly guided along the seam. An arc will also occur when the electrode is tapped on the surface.

To get a stable arc, you need to properly adjust the current strength. If it is insufficient, the arc will go out very quickly, and the electrode will “stick”. When the current strength is high, the metal splashes in all directions, it starts to burn.

During operation, the electrode melts, it gradually decreases in size. In this regard, you need to constantly move it to the part, keeping the right distance for a stable arc. If this is not done, the arc will quickly go out.

During the welding process, a weld pool is formed, which is a liquid mixture of molten metal and a coated melting metal core. When there is a constant smooth movement of the electrode with a sustained gap, the quality of the seam will turn out to be the most reliable, the mechanical performance will be at its best. The seams will look aesthetic.

After welding, slag is formed over the entire surface of the weld.

It is removed with small hammer blows. Then the seam is cleaned with a metal brush. To learn how to cook metal with high quality, you need constant training, the desire to get excellent quality work. Before starting independent work, it is worth seeing how experienced welders work.

Of course, welding is a very complex and difficult business. It is almost impossible to instantly master all the nuances of this case. It will take a lot of time to master all the tricks of welding. When experience and work skills appear, it will be possible to obtain original and beautiful products with the help of welding.

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Ceiling seam welding. The sequence of work.

The overhead weld is considered to be one of the more difficult types of welding because the weld pool is upside down. Welding ceiling seams requires the exact sequence of all actions. If you do not follow the rules and recommendations, you can get a poor-quality connection, which is fraught with smudges of hot metal.

When performing a ceiling seam, you must follow safety precautions and protect your face and hands from the possible ingress of hot metal drops.

Features of the ceiling seam technique

Note! Preparatory work before welding ceiling seams is accompanied by a number of difficulties. This is due to the fact that during the welding process, molten metal can flow down and accidentally get on the skin of the person who performs the weld. That is why experienced specialists, knowing how to weld such a seam, use special welding techniques that ensure strict adherence to safety rules.

Before connecting the ceiling seams, you must clearly understand all the requirements and not neglect the fulfillment of the prerequisites. This information is especially important for beginner welders.

If your workpieces are more than one centimeter thick and you do not know how to weld a ceiling seam, then be aware that in such a situation, welding should be done in stages. At the very beginning of work, it is necessary to use an electrode whose diameter does not exceed 3 mm; at all other stages, an electrode with a diameter of 4 mm is taken.

Note! Welding a ceiling seam involves the creation of not only horizontal seams, but also joints along a certain slope (from 10 to 80 ° C). In this case, both manual welding and semi-automatic welding can be used. You can also use arc welding using coated electrodes

As already noted, the main distinguishing feature of such welding is based on an inverted weld pool and holding hot metal by tension. It is very important to respect the minimum size of the bath and occasionally move the electrode aside so that the metal has time to cool and set. In addition, this welding method will protect your connection from cracks.

Welding methods

Crescent, this method involves the location of the electrode at an angle of 90-140 ° to the surface. With the help of oscillatory movements in an arc, it moves in the direction from edge to edge.
Ladder, here the electrode is placed in the same way. He is taken away from the hot metal and returned back.
Reverse forward method. In this case, the electrode must be constantly returned to the frozen seam.

The first method is considered the simplest and is well suited for inexperienced welders. Options involving ladder and reciprocal welding are more complex and time consuming. But such a connection will be of better quality.

Stages of work

Initially, the places that will be welded must be well processed by cleaning the edges with a grinder or a metal brush. Then the root of the seam is boiled with an electrode (3 mm). Through it, a roller of molten metal is formed. If it is necessary that the roller be on the reverse side, then the electrode is directed into the gap with small short throws. Watch and control the even burning of the arc. The resulting roller must be freed from slag. If its shape is too convex, then it is necessary to bring it to pure metal. As already mentioned, in the following steps, an electrode with a large diameter (4 mm) is used.

In order to obtain a reliable and durable seam, all safety rules should be followed. Not only the quality of the seam, but also your personal safety depends on compliance with the rules.

Be sure to isolate all wires, and when you stop work, turn off the welding machine altogether. So you protect yourself from electric shock during the welding process.
It is recommended to carry out welding of ceiling seams in a warm, dry room.
Never work in rainy or snowy weather. Welding in wet areas can only be carried out by specialists with extensive experience, but even in this case, extreme caution should be exercised.
Wear special protective clothing, mask and goggles. The whole body must be tightly covered with clothing.

In conclusion, it is worth noting once again that the welding of ceiling seams is a rather laborious and energy-consuming process. It is quite difficult for a novice welder to perform this type of connection. In order to perform the work qualitatively and create a good, durable seam, you need to gain special knowledge, master the technique of working with a welding machine and familiarize yourself with all the nuances of this type of work. It is better to practice welding some parts first. If you do not have enough knowledge and experience, then it is better to entrust this process to specially trained people. In any case, both experienced welders and beginners must strictly follow the safety rules. Accurate compliance with all prescriptions and instructions is the key to your personal safety.

How to properly weld. How to put the weld

One of the most uncomfortable and difficult positions for welding is overhead. But it is worth mastering this type of connection due to the automatic increase, which has learned to apply high-quality seams in such a spatial position. This is in demand at enterprises whose activities are related to laying, and at construction sites. This skill will come in handy in everyday life, when welding heating or gazebos. Some elements of a metal garage cannot be assembled without welding joints at the top. How to cook a ceiling seam with electric welding? What are the main precautions and optimal machine settings?

Many welders do not like ceiling seams because of the difficulties in their execution. The result for a beginner can often be poor, which discourages learning. But if you understand the main problems and prevent them as much as possible, then pretty soon, after training, you can master this difficult connection.

Welding a ceiling seam with an inverter or transformer is significantly different from working on a similar product in the lower position. When metal is welded on the floor, the weld pool spreads over the joint, and the welder only needs to ensure that the joint is correctly filled, preventing slag from entering in front of the pool. When the ceiling serves as the working surface, the molten metal tends downward under its own weight.

The slag, being in a liquid state, also constantly drips, which makes it difficult to conduct a seam. These splashes, hitting the ground, scatter even more, falling on the welder and surrounding objects. The main difficulty in arc welding in the overhead position of the seam is the connection of the sides of the product. The weld pool is formed on one edge, but it does not work to bind both sides with metal.

Welding of ceiling seams is carried out at a reduced current, which leads to frequent sticking of the electrode and lack of fusion. One more. The position of the body with the head thrown back and the arm raised up quickly tires the welder. Therefore, frequent breaks are simply necessary for the quality of work. Understanding these complexities will help you tune in to the difficulties and take steps to make the process easier to implement.

Ceiling welding technology

To figure out how to properly perform this type of connection, you need to know the basic rules used by experienced welders. Additionally, you can see how to cook a ceiling seam by electric welding on video. Here are the main points:

The sides to be welded should be brought together as much as possible. Welding with gaps on the ceiling is only available to experienced professionals, so the tighter the parts are mated, the easier it will be to weld.
The cutting of the edges is carried out as in the lower position. With a side thickness of more than 5 mm, a V-shaped bevel is made.
The electrode is brought to the ceiling at an angle of 45 degrees relative to the upper plane. Beginner welders may want to try welding with half of the electrode, as this will allow better control of its tip and control of the formation of the seam.
The welding process and the seam itself in this spatial position are possible due to the surface tension of the metal. To prevent drops of molten iron from flying off without having time to catch on the edge, the current strength should be reduced.
If the sides are closely brought together, then the first seam on even plates can be made without oscillating movements. This will fill the joint well. The second pass is made wider to strengthen the ligament. But on pipes it is better to immediately cook with a wide seam.
Welding with an electrode can be performed in several ways: crescent, horizontal figure eight, or spiral. When there is a small gap, an intermittent arc is used to allow the deposited drop of metal to cool. After a moment, not allowing the red color to pass (this can be seen through the mask), the next drop is applied. This is a long process, so the welder does not need to rush and needs to rest periodically.
You should not be afraid of the type of connection after completion of work. Slag can flow down in several tiers. But after repulsing it, a high seam should remain. Influxes and large rollers are not critical.

Apparatus and electrodes

Ceiling seams can be made with an inverter or a conventional transformer. It is important to correctly set the current strength, which is 25% lower than when welding on the floor. For example, for plates with a thickness of 5 mm, 100A is enough. It will be easier to work if the cable is not heavy. This will make it easier to control the end of the electrode and the hand will get tired less. You can also loop the cable around your hand to reduce the strain on your wrist.

Electrodes for ceiling welding are suitable with a diameter of 3 and 4 mm. It is important for them to reduce the amount of spatter. If beginners use short electrodes, this will allow them to more confidently manipulate the arc.

Precautionary measures

With ceiling seams, it is worth dressing in a tight jacket and trousers. Gloves must cover the cuffs, otherwise the scale will roll up to the elbows and burn the skin. A hat or cap without a visor is required on the head. It is important to choose trousers of such length that they close the collar of the shoe to prevent molten particles from entering inside.

Since the spray spreads farther when it hits the ground, there should be no flammable objects nearby. You need to beat off the slag in goggles, because it will fall down on the welder. Frequent rest will allow you to remove the load from the muscles of the neck and arm and do the job efficiently.

Welding in the ceiling position is not mastered immediately. It takes practice and patience. It is good to set aside a few minutes a day and weld two pieces of a pipe or corner to the table, try to weld them from below. Having mastered this method, you can safely weld pipes and metal structures of any complexity.

› How to cook with electric welding: we weld metal pipes and make beautiful seams.

Welding is one of the most reliable ways to connect parts. It is used in industry and in normal daily life. Every home master uses welding from time to time. It’s good if he knows how to cook himself, but often you have to turn to specialists. But welding can be learned. 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 done only with experience. Let's look at the basics of technology and some of the tricks of the welding process. Where to start - the preparatory stage FIRST All you need to do is prepare the equipment. You will definitely need a welding machine, a set of electrodes, a slag hammer and a brush. The electrode diameter 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 direct current necessary for welding. Before work, it is necessary to prepare protective equipment, which includes a special mask with a light filter, suede gloves and long-sleeved clothing, as well as Necessary toolsWelding process technology Welding is a high-temperature process. For its implementation, an electric arc is formed and held from the electrode to the workpiece to be welded. Under its influence, the base material and the metal rod of the electrode are melted. It is formed, as experts say, welding

In the modern world, a weld is found almost everywhere, in any industry. But many owners resort to the services of specialists. But this skill can be easily obtained by yourself, especially since the welding process is very exciting, you can be drawn from welding an ordinary garage to making an openwork fence. It is not difficult to learn how to cook, it is enough to deal with the nuances and you can safely proceed to the welding process.

Before you start any training and understand how to cook with electric welding correctly, you need to stock up on certain accessories. For welding, you need to purchase:

Welding machine - electric welding.
Set of electrodes. Their diameters are different and they must be selected depending on the density and thickness of the metal section. Needed to supply current to the weld. For beginners, you can purchase rods with a heating and easily melting composition.
Rubber gloves with long sleeves. It is recommended to wear suede.
Mask with dark filter.
Tight clothing.
Hammer, necessary for knocking down slag (glassy material).
Seam brush.
Transformer - used to convert direct current to alternating current. It is used, as a rule, when there is no need for a high quality weld.
Rectifier.

Instead of a transformer and a rectifier, you can use a simpler mechanism for a beginner - an inverter. It is very comfortable and versatile. They can weld both aluminum alloys and strong steel alloys. It also comes with a pair of wires with clips attached to them. An electrode is inserted at one end, and the parts necessary for welding are attached to the other.

When welding, do not forget about safety measures.

Before starting welding work, it is necessary to prepare the work surface. To do this, remove rust from the surfaces by treating it with a sandpaper, grinder or sandpaper. If you ignore this procedure, you may experience problems when starting the arc.

Electric Welding Process Technology

Welding is a process cultivated under the influence of high temperatures. Under its influence, the treated surfaces are melted, forming a so-called bath, in which the base metal is mixed with the metal core of the electrode.

The size of the resulting pool can be different, depending on the initial type of welding, position to the surface, the speed of movement of the arc, and so on. On average, the welding width can be 0.8 - 1.5 cm, the height is 1 - 3 cm, and the depth is about 0.6 cm.

Oxygen, when combined with metal, can have an undesirable effect on the joint of the seam, which is why the electrode is covered with a special coating, which, when melted, forms such a zone of gas in the arc region and above the molten bath, into which air does not enter. That is why the metal does not interact with oxygen. In addition, slag is formed over the seam, which also prevents the interaction of the alloy and oxygen. At the final stage, it is brushed off.

Arc strike training

Before any kind of activity, you need to gain experience. So in the welding process, before proceeding with the alloy of several metals, it is necessary to practice by making rollers on an unnecessary sheet of metal. To do this, you need to clean the rusty surface and the dirt on it.

Then the electrode is clamped in the holder of the welding machine (inverter). Further, in order to deliver current to the melting zone, you just need to strike. Or you can also do it with tapping movements.

After the completed electric arc is created, the electrode is directed to the workpiece. It should be noted that the gap between the electric arc and the metal surface should be the same throughout the gap, but not less than 0.3 cm and not more than 0.5 cm.

Important! If the gap between the arc and the metal is changed, then the electric arc will break, and the weld will turn out to be flawed, ugly.

The electric rod is held, as a rule, at an angle of 71 degrees. It can be tilted forward or backward, as it will be more convenient for the master. In the future, the slope can be changed depending on the convenience of the master or on the specifics of welding.

And also at this training stage, it is necessary to feel the necessary strength of the electric welding current in order for the feed to be carried out stably. If the current strength is small, then the electric arc will go out, and if, on the contrary, it is large, then the metal will begin to melt. Welding skills can be acquired through trial and error.

Welds depending on welding speed

Correct electrode movements

After training with rollers, which after hard training should turn out to be approximately even and beautiful, you can start training the welds. It is at this stage that you can understand how to properly lay the perfect seams by electric welding. This stage is already feasible for beginners who have well filled their hands on the rollers, felt the necessary current strength, the distance between the gaps, etc.

For the seam to be welded, you must first prepare the equipment as described above (ignite the electric arc). A distinctive feature from the previous stage is that this time the hand of the master does not move in a straight line, but along an oblique path, making slight oscillatory movements with a small amplitude. It looks as if the master moves hot, melting metal from one edge of the welded element to the other.

The movement can be different and be a zigzag, loopy or repetitive curves like Christmas trees and sickles.

There are trajectories produced in three directions:

Translational. The movement of the electrode occurs along its axis. To do this, it will be sufficient to maintain a stable length of the electric arc.
Longitudinal. This is one of the thinnest types of seams. It looks like a thread. In order to apply it, it is necessary to maintain a height depending on the speed at which the electric rod moves. In order to fix the resulting seam, it is necessary to do the transverse directions of movement.
Vibrational. This trajectory helps to obtain the required seam width. You can make them by making oscillatory movements of the hand. The height of the oscillatory wave is selected based on the size of the desired joint.

Electrode manipulation

Training also needs to be done on an unnecessary metal sheet. First, draw a line with chalk so that it can be seen through the darkened glass of the welding mask. Next, along this line, it is necessary to draw a seam with an electrode along one of the paths listed above. After the joint has cooled, slag is beaten off with a hammer, and a beautiful seam is obtained.

After obtaining these initial skills, you can safely proceed to welding the connecting seams. They come in completely different shapes: horizontal, vertical, angular, butt, overlap and others. After you feel that your hand is moving more or less confidently, you have trained a lot, only after that you can try to weld beautiful and openwork seams.

For a visual perception of the welding process, we recommend watching this video

Thus, you can independently learn a very necessary skill in working with electric welding. To do this, you need to stock up on certain accessories and tools. And also it is worth remembering that welding is a very dangerous occupation, therefore, when working with it, special equipment and protective measures are required (helmet, gloves, clothing). To master this type of work, you must first practice on an unnecessary sheet of metal.

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