How to weld a butt seam correctly

Welding fillet welds: technique, features, rules and nuances

It is difficult today to imagine construction or installation work where it would be possible to do without welding seams at an angle.

High strength of metal products welded in this way is ensured. True, without sufficient experience, it is better for a welder to gain some experience first.

The process takes a lot of time and is quite labor-intensive; you need to know a number of subtleties inherent in fillet welds. In our article we will characterize welding of this type and find out how accessible it is in everyday life.

Characteristic

What is a fillet weld? Docking by welding at an angle of up to 180 degrees, for example, pipes or other metal configurations. In the process, sometimes you cannot do without the so-called bayonets, the angle of the sides of which is –90 degrees.

This distance must be maintained, then each side will experience an equal load, and the configuration will increase in strength.

Fillet weld connections:

• overlap;
• with edges adjacent at the joining point;
• T-type (flat surface and one welded end);
• with and without edge trimming.

The classification of seams is determined by the way they are laid. They can be continuous or intermittent. Short ones are those whose length does not exceed 250 mm, long ones – from 1000 mm, etc. As you can see from here, there are also averages.

Let's talk about them in more detail. The middle ones begin at the junction of the parts of the metal configuration, and their end point will be their edges. Their length ranges from 250-1000 mm.

Possible problems

The strength and quality of the seam will depend on how completely you can avoid the defects characteristic of this type of joint. The main flaws include the following:

1. Undercuts. An electric arc contributes to their appearance. Traces of her “cunning” appear in the form of small depressions on the surface of metal products. When welding from below, the damaged area can be closed by welding filler material. You just need to hold the electrode longer. However, the technique for making a fillet weld is much more complex. It takes a lot of effort to fuse the additive onto the side surface. This is why fillet welds usually only have indentations on one side.
2. Lack of penetration on seam sections. They are more common among those welders who still need to accumulate knowledge in the technology of producing fillet welds. This factor affects this: the worker, in order to fill the joint, moves the electrode tip too vigorously on both sides. But the molten mass, on the contrary, flows down them, and the goal - welding the suture root - remains unattainable.
3. Incorrect leg. The quality of fillet weld welding here depends on the ability to determine the required voltage mode, and then control the electrode at the required speed, trying to keep it at the same level. Is the current insufficient? The electrode operates at low speed, and the leg will be excessively convex. It follows that the base metal has not melted sufficiently. Increased current and faster electrode speed? The leg will be concave.
4. Oblique angle. Welding joints usually differ in the corresponding shape to the degree of angle. This is the difficulty - maintaining the exact dimensions. The quality of the design will be hopelessly damaged when the attachment plate suddenly develops a slope towards one of the sides.
5. Uneven metal deposit on the joint sides. High t, the heaviness of the edges and the electrode provoke the molten iron mass to flow down and immediately to the sides. As a result, it may happen that the main part of the seam is located on the lower surface. The upper edge, only tacked by welding, is vulnerable to deformation. A little load and it fell apart.
6. Other defects. They are represented by voids, holes, ubiquitous cracks, unpredictable fistulas and craters, and other foreign solid inclusions. They can make themselves known in the process.

Process specifics

Remember, the sides and joints must be prepared in advance before welding begins. The welded planes themselves must form a right angle.

One will go horizontally, the other in a vertical direction. This must certainly be taken into account in T-type connections.

For them, the preparation of the vertical edge is carried out taking into account the thickness of the sheets that are to be cooked. With a thickness of 12 mm, there is nothing to prepare. In the range of 12-25 mm, the edge is cut in a V-shape.

At 25-40 mm, U-shaped bevels are made on the edges of the surface (which is vertical) in one direction. When the thickness is more than 40 mm, there should be V-shaped bevels on both sides.

In contrast to T-type welds, the overlap type of fillet welds does not require pre-processing of the edges. Seams are welded in both corners, which are formed as a result of combining metal sheets by overlapping each other.

A traditional fillet weld is formed by two parts of a metal structure connected to each other. Here you only need to trim the end of one of them.

How to weld

The production of fillet welding is influenced by the location of the plane. Let us characterize the basic methods of conducting the process.

Lower. Here it is more rational to use a technique known as the “boat”. It will give the required quality to the seam; note that even debutants in the field of welding can cope with it.

The configuration is given a V-shape. It becomes like a boat. That’s why the method was called that.

“Boat” almost eliminates the appearance of defects in the form of lack of penetration or undercut edges. You have to try hard for them to suddenly form. In practice, fillet weld welding sometimes takes place in conditions that are not as comfortable as described above.

For example, when T-seams, which have both a vertical and a horizontal surface, are welded with a “boat” at the joint of parts.

Here the quality may already be at risk. Even in a horizontal plane, the top of the corner itself risks remaining poorly cooked. The vertical plane is vulnerable to undercuts.

This will be facilitated by molten iron, which, it is possible, will try to “escape” down. A simple control trick to which the electrode reacts sensitively will prevent undesirable consequences.

The welding line must be carried out using gentle oscillatory movements.

Recommendation. Here, a single seam will be suitable for the electrode, and the leg will be 8 mm.

Results and conclusions

Lack of penetration will not spoil the horizontal plane in the lower version if you excite the welding arc at a distance of 3 or 4 mm from the very edge of the leg.

Then the arc is directed to the top of the seam and held. Whether your part will cook well depends on following these rules.

To weld a strong fillet weld, you must follow the procedure during its production. Fillet joints are available using almost all types of welding machines.

At the same time, do not forget about safety precautions. Before welding, put on protective overalls and a mask.

Source: https://prosvarku.info/tehnika-svarki/svarka-uglovyh-shvov

Methods for welding vertical seams

Welds are classified according to many parameters. The main characterizing features are the type of connection and position in space. Based on the type of connection, they are divided into butt and corner.

They can be located in space strictly horizontally (lower), vertically or at an angle to the horizon. Welding the bottom seam is the simplest. In this mode, it is easiest to control the condition of the weld pool, and therefore the quality of the connection.

When making other seams, including vertical ones, a certain skill is required and it is necessary to know the methods of welding metals and their alloys in one position or another.

Electroslag method

Electroslag welding can be used to weld parts of almost any thickness. The connection occurs in one pass, regardless of the thickness of the metal. This is its functional feature.

Moreover, welding vertical seams with this method works best, again due to the principle of the method used. Thanks to single-pass welding, energy and consumables are saved, and productivity increases by an order of magnitude. Welding of vertical joints of tanks is of high quality.

During electroslag welding, in the area between the edges of the joints of the workpieces and the copper plates, a bath of liquid slag appears. The welding process can be described as follows:

• after immersing the electrode in the slag bath, the welding current passes through it and heats it to such a temperature that the edges of the parts and the electrode itself begin to melt;
• the melt forms a weld pool, after cooling which crystallizes and forms a welded joint;
• As the seam cools, the electrode with copper plates, forming a closed area of ​​the weld pool, rises.

Thus, vertical welding of seams of any thickness is carried out in one pass. Liquid slag, as a lighter component, is always on top, protecting the seam from exposure to atmospheric oxygen. After completing the welding process, the cooled slag is tapped with a hammer and removed.

Electric arc method

Before any welding begins, the areas to be joined must be prepared. Depending on the thickness of the metal and the type of connection, it is prepared and the edges of the parts are cut in accordance with the requirements of the standards.

Then they are secured using special clamps or other devices. To prevent temperature deformations, parts are welded to each other at a certain distance with transverse seams, so-called tack welds.

They provide reliable fixation of products relative to each other.

When welding vertical joints of products using electric arc welding, the molten metal moves downward under the influence of gravity. The transition of the liquid alloy electrode into the weld pool occurs by droplets.

To ensure that the drops do not come off but flow smoothly, a short electric arc is used. Sometimes, it is even possible to touch the end of the electrode to the workpiece being welded to prevent it from sticking to the workpiece.

A vertical seam is welded in two ways: top-down or bottom-up.

Down up

With bottom-up technology, the weld pool is initially located at the bottom. Molten metal enters it from above. To prevent liquid metal from spilling, the welding electrode is installed at an angle to the plane of the vertical weld.

Its melting end is located above the other end, fixed in the holder. Thus, it kind of supports the weld pool and prevents the metal from splashing.

The lower layers will crystallize and become a kind of stand for the new bath. This is how the manual arc method of creating a vertical seam is carried out.

With any method, it is necessary to maintain the welding current so that the crystallization of the pool occurs faster than the melting of the electrode and edges. This is achieved through a short arc and the formation of small drops of liquid metal.

Top down

When welding vertical joints using the top-down method, the electrode is also positioned end up. The edge of the weld pool is supported by an electric arc and electrode.

The task is to advance melting of the lower edge of the bath while simultaneously holding it. The upper edge must have time to crystallize due to the lack of heat input from the molten electrode.

If splashing still occurs, then you need to increase the welding current and increase the speed of moving the electrode down. It is also advisable to increase the width of the seam.

The vertical welding seam produced by an inverter is better than when using a conventional machine. This is due to a more stable welding arc.

Use of a semi-automatic device

Welding of vertical seams using a semi-automatic device or an inverter machine is carried out using several welding technologies. The choice of method depends on the thickness of the walls of the products, the gap between the joints, and the shape of the edges.

Triangular trajectory

Triangle welding technology is used if it is necessary to connect products up to 2 mm thick. This method requires the greatest dulling of edges.

The technology can be used when welding fillet welds in a vertical position or tanks. Welding is carried out from the bottom up, so the molten metal is located on top of the cooled alloy.

The flowing slag does not interfere with the penetration of the edges, since it flows down the hardened metal. First, a shelf is formed at the bottom of the joint. By moving the electrode to one of the edges, the edges are melted and the weld pool is filled.

The electrode is then moved to the other edge and the process is repeated. The shape of the bathtub looks like a triangle, hence the name of the technology. The recommended electrode thickness is 3 mm at a welding current of 80-100 amperes .

Trajectory in the form of a Christmas tree and a ladder

When welding products with a gap of 2-3 mm, the herringbone technology helps. In this method, it is necessary to use complex movements with the end of the electrode.

The process of welding a vertical seam begins from one of the edges, from the depth of the gap.

The electrode seems to be pulled out from the thickness of the metal, while fusing the metal onto the plane of the edge. Then it again returns deep into the future seam, and surfacing is carried out on the other side of the gap.

Gradually, the vertical gap is filled, forming a strong connection. The process is repeated until the entire gap is filled with molten metal. the task is to prevent the formation of excessive penetration of the edges and the appearance of metal leaks.

The ladder technology is used to weld vertical seams with the largest gaps, when the edges are not blunted at all. The electrode moves from one edge to be connected to the other, rising a minimum distance upward.

The movements are zigzag, with a brief stop at the edges for metal penetration. The technology allows welding products up to four millimeters thick.

Source: https://svaring.com/welding/teorija/svarka-vertikalnyh-shvov

How to properly and efficiently weld a vertical seam using electric welding

Very often it is necessary to weld various metal parts and fragments of parts. There are several methods that will help achieve the task, but electric welding is used much more often than others.

Welding with non-consumable electrode.

Basics of the electric welding method

This method is based on the formation of an electric arc. The arc forms a depression at the point of contact with the metal. This recess is filled with molten metal resulting from the combustion of the electrode. As it moves along the surface to be welded, its edges heat up and melt, forming a single structure with the metal of the electrode.

Homemade welding machine for DC welding.

An important factor in electric welding is the current strength. If it does not have sufficient parameters, the arc will go out all the time and the electrode will stick to the surface being welded. The required current strength should depend on the apparatus used. If an inverter device is used, then the required indicator should vary in the range from 80-100 A. When using a transformer-type device, the range should be in the range of 35-55 A.

Electrodes for work should be selected taking into account their chemical structure and the structure of the processing surface. There are several types of such metal: steel, stainless steel, aluminum. All electrodes have appropriate markings, which allows them to be selected correctly. When using an electric welding machine, you must remember that the diameter of the electrodes must be selected relative to the thickness of the material being processed.

Vertical seam welding

Before starting work, you need to decide what kind of seam you need to make. There are several main types of seams:

1. Welding of flat sheet joints.
2. Vertical seam.
3. Fillet welding connection.
4. Welding of tubular joints.

When performing vertical welding and obtaining a clear and even seam, the process diagram must be followed. To do this, the prepared parts must be clearly recorded. Using tacks, you need to fasten them along the edges in 3-4 places. The mass must be secured to the parts using a clamp. The inclination of the electrode should be 70-75° relative to the surface.

In order to properly weld a vertical seam using electric welding, it is necessary to periodically perform rotational movements that will help rake the molten metal to the point where the 2 parts join. The end of the electrode should be located exactly in the middle of the seam. The welding process must be carried out from the bottom up, sticking drop by drop. This will help to gradually fill the gap with molten electrode wire.

Maintaining the correct angle will allow the molten electrode wire to flow evenly. The more evenly it flows, the smoother and better quality the seam will be.

After the surface of the seam has cooled, use a hammer to knock off the slag from the surface of the parts. It is formed during work from metal combustion products. The seam is ready, but the more often welding work is done, the more accurate and high-quality it will be.

Completion of work

After welding is completed and the surfaces of the parts are cleaned from slag, frozen deposits and scale, it is necessary to inspect the resulting joints. A control inspection should be carried out to detect any metal burns, cracks, craters or resulting pores. If they are present, this will indicate poor quality work done.

If poor-quality seams are discovered, it is necessary to immediately restore the seam, without waiting for a break. To do this, you need to thoroughly clean the entire surface using a file and a wire brush. Then repair it. Restoration should be carried out only in those places where defects were discovered. There is no need to overcook the surface completely.

During work, we must not forget about safety precautions.

The entire process must be performed in suede gloves, which should be covered with rough mittens. A welder's mask, tarpaulin boots and canvas overalls are required.

There should be a fire extinguisher, sand or a container of water nearby. If you follow all the above rules for welding work, you can achieve a high-quality weld that will not lead to fracture of the finished structure.

Source: https://moyakovka.ru/process/kak-varit-vertikalnyj-shov-elektrosvarkoj.html

Butt weld | Metal welding

One-sided butt welds without beveled edges are made with coated electrodes with a diameter equal to the thickness of the sheets being welded, if it does not exceed 4 mm. The current is selected depending on the diameter of the electrode, the type and thickness of the coating (Table 6). Sheets without beveled edges with a thickness of 2 to 8 mm are welded with a double-sided seam. The position and lateral movements of the electrode during welding are shown in Fig. 29.

Bevel connection

Butt joints with bevels of two edges, depending on the thickness of the metal, are made with single-layer, multi-layer or multi-pass seams.

Rice. 29. Position (i) and movement of the electrode (b) when making butt welds with beveled edges

Single layer seam

Metal with a thickness of 1 to 6 mm without beveled edges is welded with a single-layer (single-pass) seam.

Single-layer seams with a bevel of two edges are performed by transverse oscillatory movements of the electrode in the form of triangles without delay at the root of the seam (sheets 1-4 mm thick) and with delay at the root of the seam (4-6 mm thick).

Sheets with a thickness of 12 mm or more are butt-joined with two asymmetrical bevels of the two edges using a multi-layer or multi-pass seam.

Table 6. Approximate welding conditions for butt joints without beveled edges

Metal thickness, mm	The seam	Gap, mm	Electrode diameter, mm	Average current value, A
bottom seam position	vertical and ceiling position of the seam
3-4	Unilateral	1,0	3-4	180	160
5-6	Bilateral	1,0- 1,5	4-5	180-260	160-230
7-8	»	1,5-2,0	5	260	230
10	»	2,0	6	330	290

Note. The maximum current values ​​must be specified according to the electrode data sheet.

Multilayer seam

A multi-layer seam is performed faster than a multi-pass seam. The choice of a multi-layer or multi-pass weld depends on the chemical composition and thickness of the steel being welded and on the installed welding technology.

Each layer of a multilayer weld has a cross-section increased several times compared to the cross-section of each bead in multi-pass welding. The modes of arc welding with coated electrodes of lower butt multilayer welds are given in Table. 7.

Table 7. Approximate conditions for butt welding of steel sheets with bevel of two edges

Metal thickness, mm	Gap, mm	Number of layers, except for under-welding and decorative	Electrode diameter, mm, when surfacing	Average current value, A (lower position of the seam)
first	Subsequent
10	1,5-2,0	2	4	5	180-260
12	2,0-2,5	3	4	5	180-260
14	2,5-3.1	4	4	5	180-260
16	3,0-3,5	5	4	5	180-260
18	3,5-4,0	6	5	6	220-320

Note. The maximum current values ​​must be specified according to the electrode data sheet.

Multi-pass seam

A multi-pass seam is performed with thin and narrow rollers, without transverse oscillatory movements of the electrode. Welding is recommended to be performed with electrodes designed for support. In this case, electrodes with a diameter of 1.6 to 3 mm (rarely 4 mm) are used. The entire multi-pass weld can be performed with electrodes of the same diameter.

Sometimes, to ensure penetration throughout the entire thickness of the metal, welding is carried out on a copper lining 4-6 mm thick. In this case, the welding current can be increased by 20 - 30%. If the design and purpose of the welded product allows through penetration, welding can be carried out on the remaining steel backing.

In especially critical structures, before welding the seam, it (from the reverse side) is first cleaned with a surface cutting torch or cutter to remove possible defects (lack of fusion, cracks, gas and slag inclusions).

Seam opening angle

The optimal opening angle of the seam is determined by the following considerations. A large cutting angle (80° - 90°) provides greater convenience to the welder, reduces the risk of lack of penetration of the weld root, but increases the volume of deposited metal, therefore reducing productivity and increasing deformation of the product. For the normal manual arc welding process, the groove angle is (50 ± 4)° (welded joint type C17).

The gap between the joined elements and the blunting of the edges ranges from 1.5 to 4.0 mm, depending on the thickness of the sheets, the welding mode and the nature of the structure being welded.

Weld root penetration

The most difficult thing when welding is to obtain complete (reliable) penetration of the root of the weld. Here, most often, there are defects, such as lack of penetration, gas and slag inclusions. Therefore (if possible) the root of the seam should be welded from the reverse side.

Source: http://www.svarkametallov.ru/content/stykovoy-shov

Welding vertical seams

There are many types and types of welding. They are divided into different classifications depending on the material used, the apparatus and the type of conductor used to create the suture. One of these is the welding of vertical seams, which has a number of features that we will now get acquainted with.

Features of vertical welding

Vertical welding has the difficulty that when creating a seam, the molten metal tends to flow down, which in no case should be allowed. If this happens, then it will no longer be possible to cook on top of this drop, since it contains slag from the electrode.

To create a high-quality track when manual arc welding, it is recommended to use a short arc at a low current. At the same time, the master must make movements from the bottom up to avoid unnecessary drips. When vertical seams are formed from a molten drop, you need to move the end of the electrode a little to the side to allow the material to harden without losing the spark.

Principles of vertical welding

To create an ideal seam, you must adhere to several principles of vertical welding:

1. If welding work is carried out using alternating current, then it is imperative to start from the bottom. In this case, the weld crater is filled with material so that it creates a volumetric roller, which in parallel serves as a kind of support for the molten metal located slightly above. This is how the seam is filled.
2. With the electric arc method, the metal in the weld crater in a vertical position should harden much faster. For this it is better to make small drops. It is very simple to achieve this effect by shortening the arc (the distance between the product and the electrode).

Conditions for a high-quality vertical seam

Not all novice welders understand how to weld a vertical seam so that it turns out aesthetically pleasing, durable and “correct” in terms of quality. There are several conditions that will ensure that you get a perfect seam almost the first time:

• during arson, it is necessary to maintain a perpendicular position of the electrode in relation to the parts;
• the shorter the arc, the faster the metal crystallizes and the risk of drips that spoil the seam is reduced;
• during the formation of the track, the electrode must be tilted so that metal drops do not flow down;
• if due to carelessness the material flows, you need to increase the current strength and the width of the seam. This maneuver will give more time for crystallization.

With this approach to work, the seam is made easier and simpler than when moving downwards. But the quality of the seam will be slightly lower.

Considering that there are parts that need to be welded only using the method from above. To do this you need to be careful and smooth. Then the metal will not drain and damage the product. If the plates being welded are very thin, for example tin or galvanized, then you need to do the following:

• clean the parts as efficiently as possible, remove dust, dirt, paint or oil residues from them, remove the galvanized layer;
• make the seam with dots. In this case, the risk of drips and burns is reduced.

Vertical welding technology

The technique of welding vertical seams depends on several factors:

• characteristics of the metal of the materials that need to be connected;
• the type of welding that is used in this case;
• welder skill:
• quality and features of the equipment used.

You can create welds in several ways:

• from top to bottom with arc separation:
• from bottom to top with arc separation;
• from top to bottom without breaking the arc:
• from bottom to top without breaking the arc.

Creating a seam with an electrode

Welding in a vertical position requires more attention and effort than in a horizontal position. This is due to possible metal leaks. For novice welders, it will be easier to form a weld with arc separation. Thus, the material hardens quickly. To make the process easier, at this time the electrode can be rested on the edge of the weld crater. During the formation of the track, movements are made both with the separation of the arc and without separation - with a zigzag, crescent, loops or roller - “up and down”.

If you decide to weld a vertical seam from top to bottom, then this is done with a very short arc. It will take a little practice beforehand to learn how to melt the metal, but avoid it from spreading downwards. Here it is important to hold the electrode correctly - strictly perpendicular to the edges of the crater. When exciting the arc and creating a roller, you need to tilt it down a little (45 degrees).

The recommended electrode diameter is 4-5 mm with a current of no more than 170A.

How to properly weld a vertical seam without tearing can be seen in this video tutorial:

Semi-automatic vertical seam

Semi-automatic welding of vertical seams can be done using several methods:

• “Triangle” is a technology used for thin metal, no more than 2 mm thick. It is based on the standard principle of guiding the conductor from bottom to top. In this case, the molten metal is located above the frozen metal, which has already formed a small roller and does not allow “newly made” drops to flow down the path. When making vertical welds with an inverter, it is necessary to move the conductor correctly so that the weld pool is slightly angled. Actually, this is where the name of this method comes from – triangle. For this technology, professionals recommend using an electrode with a three-millimeter diameter and operating at a current of 100A.

• The “ladder” is used when there is too much gap between the parts to be soldered. The working process itself is as follows: it is necessary to make transitions from one edge to another with minimal lifting of the electrode. It is best to implement this in a bottom-up manner without tearing off the arc. Thus, a so-called ladder is obtained. As a result, the roller is not smooth, but with sharp edges. This type of joining parts is considered the easiest.

• “Herringbone”. This technology is ideal for semi-automatic welding of gaps of no more than 2-3 mm. In this case, the electrode must be moved along a certain trajectory. And the result will be a seam like a herringbone. You need to start from one of the sides and guide it along the edge wall towards you. When the metal is melted, you need to lower the electrode and stop a little to melt the product. You need to do the same on the other side. Continue this way upward along the entire path. The most important thing is to prevent the drops from spreading.

In this video you can see how to properly weld parts in a vertical position:

In conclusion, it is worth noting that the vertical seam requires special attention, as there is a risk of hot metal running off. To avoid this, there are several technologies that allow you to cook iron in a vertical position.

If you adhere to all the rules and regulations, then you will get a high-quality and reliable seam without “sticking” layers of metal and slag. Such tracks can be welded using several methods - semi-automatic and manual welding.

Each of the methods has advantages and disadvantages when creating a seam, but choosing among all existing types, these are the best and simplest, especially for novice craftsmen.

Source: https://svarkaed.ru/svarka/shvy-i-soedineniya/vertikalnye-shvy.html

Butt welded joints: how they differ from lap joints, manual arc welding technology in the lower and vertical positions, details, video

A butt welding connection is the adjoining of two parts with their end surfaces to each other, lying on the same plane. This connection is simple and reliable, and is recommended in structures that are exposed to alternating voltages.

Where is it used?

A butt joint is used when metal thickening is excluded or not suitable , it provides a beautiful appearance without protruding edges. Butt joints are used in the aerospace and automotive industries. It is used to form a permanent connection between parts of various metal structures in the case when the surfaces of the parts lie in the same plane and are adjacent to each other at their ends .

Parts of various pipelines, shells of various containers, cylinders, tanks, sheet structures, channels, angles and other shaped profiles are butt welded.

Advantages

Pipe welding is usually done using a butt joint

For butt connection

• less electrode metal is used,
• it is not difficult to control the process, the designs are reliable,
• The welding technique is simpler than the fillet weld technique,
• butt joints ensure the flatness of the surface of the structure,
• provide connections between parts of different thicknesses,
• It is possible to weld thick metal with a one-sided seam.

Flaws

Butt joint

• does not provide additional rigidity compared to overlap,
• Significant surface deformations may also occur after welding (especially when welding thin metal).

How is it different from overlap

Welded lap joints are the fusion of different elements of a part located in parallel, partially overlapping each other. Used when butt jointing is not possible. An overlap connection is not recommended if the structure is subject to vibration; the steel thickness should be no more than 10-12 mm.

With butt it is important to take into account the accuracy of assembly , while with overlap assembly is much simpler and there is no need to cut the edges.

The disadvantage of an overlap joint will be the greater consumption of base metal, since one part covers another, corrosion of the metal may occur from moisture penetration between the parts, and it will not be easy to identify defects.

In butt welding there is no overlap (overlapping) of parts; different welding techniques are used when welding overlap joints is performed using a fillet weld . In lap joints there is no need to cut the edges; there are also a large number of types of butt joints according to GOST.

Cutting edges for welding

butt joint without beveled edges

Important! If you weld without beveled edges and the metal thickness is more than 2 mm, you need to set a gap between the parts being welded!

The quality of the seam and the product depends on the choice of bevel of the edges. For each welding method, different edge preparations are selected.

For your information! Without cutting, the process will be much more economical, but cutting the edges is necessary for complete penetration in the cross-section, which makes the quality higher.

with V-shaped edges

with X-shaped bevel edges

with curved edges

The cutting can be done with a chisel, in this case the edges will not be even, an excellent option would be a grinder, a milling machine, the best option would be to use an edge cutter (beveler). also need to control the cleanliness of the bevels in order to get a high-quality seam without defects . For butt joints, all types of edge cutting are used depending on the thickness of the metal and the nature of the seam (one-sided or double-sided seam).

There is a designation for cutting edges: U-V-K-X-shaped.
The X-shaped groove of the edges, compared to the V-shaped one, allows you to reduce the volume of deposited metal; the X-shaped groove requires one seam on each side, while the V-shaped one requires a one-sided seam. The shape of the edges depends on the welding method, the material being welded, and the thickness of the elements being welded. [ads-pc-3][ads-mob-3]

How to cook

Before starting welding, technological preparation is carried out. Parts should be marked, cut, surfaces should be cleaned of dirt and rust and dried if moisture is present.

The two parts to be welded must lie on a flat surface and have a gap of 2-3 mm between them; we ignite the electrode with a blow or “strike” like a match, and perform two tacks to avoid deformation of the joint being welded.

The video below shows what welding can lead to if you don’t use tacks (what you need to know about tacks here).

with lining (removable or remaining)

You can move the electrode towards yourself, away from you, from right to left and from left to right. Depending on the thickness of the metal and the recommended spatial position of the electrode, the method of moving the electrode for better welding is selected, and the electrode is also held at an angle of 45 degrees during operation.

After completing the seam, the slag is removed and the surface is cleaned. To avoid burns, use linings, with them the work is more confident, you can increase the current and not cook on the other side of the seam (see photo on the left).

Welding in the down position

The parts are cleaned; for thin metal, edge cutting is not performed; the gap between the parts to be welded is 1-3 mm. The assembly is carried out, the tacks are installed (after the tacks are cleaned), then welding is carried out on the back side of the tacks.

The thickness of the roller should not exceed 9 mm and the height 1.5 mm. We carry out welding from left to right, perform circular oscillatory movements counterclockwise, also weld the second side, on the second side you can increase the current, after welding we clean the surfaces.

butt joint with flange (for thin metal)

During the welding process, the electrode makes 2-3 movements.

1. The electrode is lowered down as it melts, ensuring a stable burning of the welding arc.
2. The electrode is moved at a uniform speed, tilting it at an angle of 15-30 degrees from the vertical. In the other plane, the electrode is perpendicular to the joint surface.
3. If it is necessary to obtain a weld of increased width, various oscillatory movements are used.

A short video, without much explanation, but quick, for the impatient.

Source: https://WeldElec.com/svarka/nauchitsya/soedineniya/stykovye/

How to weld a vertical seam correctly

In the article we will talk about how to properly weld a vertical welding seam with an electrode and electric arc welding, what problems are encountered in the work and how to deal with them.

Vertical welding

Welders are often faced with a situation where a welded joint needs to be carried out in different planes; this happens with ceiling and side structures. Sometimes these are parts located at an angle, in other cases they are straight, but have inconvenient access - on the ceiling. The main difficulty is that the force of attraction acts on the molten metal, so it can result in an unsightly, and most importantly, non-functional leak.

General definitions

There are several types of seams depending on where they are located. Towards:

The simplest one runs along the horizon and is located below, on the desktop. Then it is very easy to monitor the weld pool being formed, and the deposition itself is laid down neatly and consistently, regardless of how the electrode moves.

Types of connections

The welder can apply a seam on one side or on both sides; in the latter case, this increases reliability, but can sometimes be difficult. Then the forces are compensated, and no fractures or deformations occur. There are also 4 classic types of welding depending on the location of the two parts of the product:

• end-to-end - the workpieces are located with two edges close to each other, without gaps;
• T-shaped - an inverted letter “T”, that is, a vertical one is applied to a horizontal plane;
• overlap - one metal die is overlapped with another;
• corner - the most difficult, because you need to achieve the correct angle when connecting.

Let's tell you in more detail. Or you can watch this video tutorial:

Butt-butt

Mainly used when working with sheets or pipes. The gap should be no more than 1-2 mm (molten metal will be located here). The elements themselves must be rigidly fixed. Sometimes it is necessary to pre-margin the edges (bevel them to create a recess for fusing) - with a steel thickness of more than 4 mm.

Please note that the deeper the cavity, the better the connection, but the process itself uses more electrodes (filler wire on a semi-automatic machine) and takes longer. If the width of the workpiece is very large, you will need to make several successive passes.

A multi-layer weld can be filled with layers or spot welds, as in this schematic illustration:

overlap

Suitable for sheets no more than 8 mm thick. They are placed one on top of the other and boiled on both sides; otherwise, a gap is formed in which a source of corrosion can occur.

The main feature here is the angle of inclination of the electrode. It should be 15-45 degrees from the top surface. If it is less, then the seam will be on the bottom die, more - on the top. In any case, there will be no reliable contact.

How to weld a vertical seam in a T-joint or corner joint

The technology in both cases remains the same, visually the products resemble the letter “T” in the first situation, and “G” in the second. Sometimes pre-processing is required, depending on how thick the pieces are. Let's look at the table:

In electric welding, an electric arc is used to heat the metal. It occurs between the part and the electrode - a rod made of conductive metal (sometimes non-metal). The temperature of the arc melts the metal.

The fusion zone at the junction of parts is called a weld seam. For different metals and different types of joints, the welding technique, the position of the electrode, the speed of its movement, and the amplitude may vary.

How to weld a seam correctly so that the connection is not only reliable, but also beautiful, we’ll talk further.

Types of welds and joints

Seams have a fairly extensive classification. First of all, they are divided according to the type of connection of workers. Depending on the reliability requirements, the seam can be applied on one or both sides. With double-sided welding, the structure is more reliable and holds its shape better. If there is only one seam, it often turns out that the product is warped: the seam “pulls”. If there are two of them, these forces are compensated.

Welds, depending on the type of connection, are butt (butt), T, overlapping and corner (To enlarge the size of the picture, click on it with the right mouse button)

It is important to note that to obtain a high-quality weld, the metal should not be rusty. Therefore, the welding areas are first sanded or treated with a file until the rust completely disappears. Next, depending on the requirements, the edge is ground or not.

Butt joint (butt seam)

A butt seam in welding is used when joining sheet metal or pipe ends. The parts are laid so that there is a gap of 1-2 mm between them, and if possible they are firmly fixed with clamps. During the welding process, the gap is filled with molten metal.

Thin sheet metal - up to 4 mm thick - is welded without preliminary preparation (removing rust does not count, it is required). In this case, cook only on one side. For parts with a thickness of 4 mm or more, the seam can be single or double, but the edges must be sealed using one of the methods shown in the photo.

Types of preparation of parts when butt welding

• For part thicknesses from 4 mm to 12 mm, the seam can be single. Then the edges are cleaned using any of the methods. It is more convenient to do one-sided preparation for thicknesses up to 10 mm, and thicker parts are often cleaned in the form of the letter V. U-shaped stripping is more difficult to perform and is therefore used less often. If the requirements for welding quality are increased, with a thickness of more than 6 mm, stripping on both sides and a double seam is necessary - on one side and the other.
• When welding metal with a thickness of 12 mm butt, a double seam is definitely necessary; it is impossible to heat such a layer on one side. The edges are trimmed on both sides, in the shape of the letter X. Using V or U shaped edge stripping with such thickness is unprofitable: filling them requires several times more metal. Because of this, the consumption of electrodes increases and the welding speed significantly decreases.

Cutting metal edges when joining parts end-to-end (To increase the size of the picture, right-click on it)

If you decide to weld thick metal with one-sided cutting, you will need to fill the seam in several passes. Such seams are called multilayer. How to weld a seam in this case is shown in the figure below (the numbers indicate the order of laying the layers of metal during welding).

How to weld a butt seam: single-layer and multi-layer (To increase the size of the picture, right-click on it)

Lap joint

This type of connection is used when welding sheet metal up to 8 mm thick. Boil it on both sides so that moisture does not get between the sheets and there is no corrosion.

When making an overlap seam, it is necessary to choose the correct angle of inclination of the electrode. It should be about 15-45°. Then you get a reliable connection. If there is a deviation in one direction or another, the bulk of the molten metal is not at the junction, but to the side, the strength of the connection is significantly reduced or the parts remain not connected at all.

How to properly hold the electrode when overlapping welding (To enlarge the size of the picture, right-click on it)

Tee and corner connection

A T-joint in welding is a “T” shape, a corner joint is a “G” shape. A T-joint can have one seam or two. The edges can also be cut or not. The need for edge cutting depends on the thickness of the parts being welded and the number of seams:

• metal thickness up to 4 mm, single seam - no edge treatment;
• thickness from 4 mm to 8 mm - without edge treatment, double seam;
• from 4 mm to 12 mm - single seam with groove on one side;
• from 12 mm, the edge is cut off on both sides, and two seams are also made.

Types of welds: T-joint with and without cutting (trimming) edges

A fillet weld can be considered as part of a T weld. The recommendations here are exactly the same: thin metal can be welded without cutting the edges; for greater thickness, you have to remove a part from one or both sides.

Source: https://vi-pole.ru/kak-pravilno-svarivat-vertikalnyj-shov.html

T-welded connection

Welding joints in the shape of the letter "T", called "T-joints", are present in all loaded structures. They are fillet welds with a perpendicular arrangement of the workpieces. For a small area, the connection must support the design load. T-joints subject to torsion and fracture are subject to special treatment - the seams are checked for internal defects. Following technology helps to avoid them. The type of seam is indicated in the drawing.

Application area

Installation of pipelines, creation of frame structures, ceilings, fences involves the arrangement of parts at right angles. Reinforcing elements are usually attached perpendicularly by welding: beams, channels, rolled profiles. Parts at an angle of 90° are connected by T-welding. Beginning welders at home try to avoid such joints because of the difficulty of fixing parts in a given position.

In production and construction, T-joints are often used. All types of connections are regulated by GOSTs for various types of welding. They can be single-sided or double-sided, with or without edge cutting. It all depends on the expected load, alloy, thickness of the parts being welded.

Types of T-welded joints

Techniques and features of welding T-joints

When making corner joints, they control the size of the suture leg and the appearance of the roller - they make it as flat as possible. To weld the T-joint evenly, do not make sudden movements with the holder. The arc during welding should not break off during the formation of the bead. The preparatory stage includes:

• stripping of metal in the work area;
• laying workpieces at the desired angle while maintaining the required gap size;
• fixing elements with clamps or tacks.

Pipe welding

When RDS of plugs, flanges, shut-off valves in pipelines is carried out, they are guided by the requirements of GOST 16037-80. It is also used when inserting pipes of smaller diameter. On thick-walled workpieces, preliminary cutting of seams is carried out. Then tacks are made in 4 places, they are arranged in pairs symmetrically around the circumference, dividing it into 4 parts. Then a fillet seam is made.

When inserting, the end of the pipe is adjusted to fit the pipe so that it fits tightly to the surface without forming large gaps. Pipes of small diameter are “finished” with a grinder. When cutting large workpieces for welding, reamer stencils or standard templates are used.

When there are rotary tables, rotary position welding technology is used. The seam forms faster and is even. It is more difficult to weld fixed seams; the bead is formed along curved lines.

In this case, welding is carried out in several stages, in sections. The second one begins on the resulting roller, overlapping, so that the T-joint becomes airtight. Depending on the wall thickness, the pipe is welded in one pass or several.

Such T-joints must be checked using non-destructive testing methods.

Source: https://svarkaprosto.ru/tehnologii/tavrovoe-svarnoe-soedinenie

How to properly weld a vertical seam using electric welding video

Electric welding involves the application of an electric arc to the metal being processed. It is formed between the product and the used electrode made of conductive material.

Too high a temperature causes the metal to melt, due to which the individual parts are connected. The connection point is usually called a weld.

To change its indicators, the technical parameters of welding are changed, for example, the amplitude and speed of movement. The features of vertical welding should be considered in more detail.

How to weld a vertical seam?

There are quite a few rules that, if followed, can improve the quality of the resulting seam. It is quite difficult to exclude the possibility of dripping of hot metal drops.

The main recommendations include the following points:

1. The electric arc must be extremely short. A long one can cause the alloy to spread out as it flows under the influence of gravity.
2. At the time of arson, the working part is placed exclusively perpendicular to the surface being treated. It is important that it is positioned perpendicular to both surfaces being processed, which ensures high quality processing.
3. When working, it is recommended to tilt the electrode slightly downwards. By maintaining an acute angle, it is possible to retain the hot metal, preventing it from flowing down.
4. In some cases, it is impossible to eliminate the possibility of metal dripping. Then it is recommended to increase the current strength and speed up the movement of the working part. However, when increasing this indicator, you need to be careful, as this leads to an increase in the arc. In addition, it is recommended to increase the width of the seam by moving the tool from side to side.

Vertical welding methods

The above technology is much simpler to implement if we compare the option of conducting the electrode from the bottom up.

Top down technique

Moving the electrode from top to bottom can only be used to weld when using an electrode that produces a thin layer of slag. Among the features of this process, we note the following points:

1. By using such a rod in the weld pool, the material hardens faster. In this case, the molten material does not flow down.
2. It is recommended to use plastic and cellulose coated electrodes. An example is the LNO-9 and VSC-2 brands.
3. This technology is characterized by high productivity. That is why, if there is a need to increase labor productivity, then the technology in question is chosen.

Vertical seam from top to bottom

This technique is not suitable for beginner welders, as it is difficult to prevent the alloy from dripping.

Bottom-up technique

This technology is extremely common. It is characterized by the following features:

1. At the beginning of work, the welding machine rod is placed perpendicular to the surface being processed.
2. As soon as the arc has been excited and the first drops have formed, it is recommended to tilt the electrode slightly.
3. A short arc is supported by the end of the rod and the drops are collected a little, and when it is withdrawn briefly, time is given for the molten material to cool and crystallize.
4. Transverse oscillatory movements can be reported. This eliminates the possibility of a long delay of the heat source at one point.

Vertical seam from bottom to top

This technique allows you to get a high-quality seam. However, it is characterized by low productivity, since it is necessary to allow the drops to cool from time to time.

Source: https://crast.ru/instrumenty/kak-pravilno-varit-vertikalnyj-shov

Calculation of the length of the weld leg from the thickness of the metal for various types of welds

In the production of metal structures and heavy vehicles, welded joints must withstand high loads. The weld will be of high quality only if all parameters are accurately calculated before starting work. One of the important indicators is the seam leg (K).

This is one of the sides of the largest conditional triangle with equal sides, which can be inscribed in the cross section of the connection (GOST R ISO 17659-2009, which came into force on July 1, 2010). It can be measured or calculated based on the dimensions of the elements being welded.

When choosing the length of the side of the triangle, the dimensions of the workpieces, position and type of joint are taken into account. The selection is carried out for each element, but general principles are taken into account. In the household, you can use a template to measure.

In order for the connection to be strong enough, both identical sides of the triangle must have the same length (if the elements are located at an angle of 90°).

Connections can be:

• butt (without beveled edges, with one-sided, with V-shaped, X-shaped, curved bevel);
• end;
• overlap;
• corner (angle from 30°, one-sided, two-sided without beveled edges, with one or two bevels);
• T-shaped (acute or straight angle, one-sided, two-sided, without beveled edges, with one or two bevels).

Calculation of the length of the leg of the weld depending on the thickness of the metal is possible for three types of welds: fillet, T, and overlap.

Calculation of the length of the weld leg, based on the thickness of the metal, is required in industrial production, since the strength of the weld, the consumption of welding wire, and its diameter depend on this indicator (the longer the side of the triangle, the thicker the wire).

Important! If the side of the triangle is too long, the volume of liquid metal increases (due to the large heating area) and the consumption of the additive increases, and the finished product may become deformed.

The leg is also important if elements of different sizes are welded (calculations are made based on the smaller figure).

Read also: Techniques to relieve metal stress after welding

Calculation formula

The volume of deposited material is equal to the square of the leg. For example, if K increases by 1 mm at a junction length of 10 mm, wire consumption increases by 20%.

For overlapping materials with a thickness of up to 4 mm K=4. If the figure is greater, you need to take 40% of the thickness and add 2 mm.

Corner welded joints are:

• normal (without convexity or concavity) - K is equal to the thickness of the metal;
• concave - K=0.85;
• convex - K= s×cos45°, where s is the width of the junction, cos45°=0.7071;
• special (the triangle is not isosceles).

When calculating the length of the weld leg depending on the thickness of the metal, the formula is not enough - the welding method and the fluidity of the metal being welded are important.

The obtained result must be checked against the requirements of GOST 11534-75 and GOST 5264-80 or reference materials.

When carrying out welding work in the household, it is enough to establish the side of the triangle that exceeds the thickness by 1-1.5 mm, or determine the indicator from the table. There are rules that must be followed at all times. K must be less than the thickness of the thinnest element multiplied by 1.2. The length of the junction should be less than K*4.

Calculation of the leg for a 1m seam

In practice, all calculations are quite conditional, as they are based on the following premises:

• the load is distributed evenly along the entire length of the deposited filler;
• destruction is possible only through an additive layer equal to 0.7 K.

The purpose of design calculations is to determine the optimal weld size for a certain elongation and axial stress.

The optimal length of the deposited filler for tensile load is determined by the formula:

L= F/ρ*[ρ], where

L – length of the junction;

F – planned actual load on the connection;

ρ – permissible load on the connection.

Optimal length for axial stress:

L=F/0.7K*ρ

From this formula we can derive a formula for calculating K for a deposited filler length of 1 m:

K= 0.7*L*ρ

K=0.7*ρ

This means that K completely depends on the magnitude of the permissible load.

Permissible loads in compression, tension and shear for various welding methods are determined in special tables.

When developing design documentation:

• select the welding method, type of welding, brand of electrode (wire);
• determine the standard permissible load;
• calculate the length of the joint for tension and axial stress;
• create a connection drawing;
• specify the technical characteristics and dimensions of the elements being welded.

When developing design documentation for welding, determining the exact size of the weld leg from the thickness of the metal and the optimal length of the weld is carried out in order to improve the quality of the work and minimize its cost. It is important to obtain strong and reliable connections at minimal cost. This indicator is especially important at large industrial enterprises that produce metal structures that must withstand increased loads during operation.

Source: http://solidiron.ru/obrabotka-metalla/svarka/raschet-kateta-svarnogo-shva-ot-tolshhiny-metalla.html

Electrode welding vertical and ceiling seam

Electric welding technology is based on the principle of melting metal through an electric arc that occurs between the workpiece and the electrode. The temperature of the arc melts the metal in the welding zone, which allows the metals to be joined through a weld. For different metals and types of joints, certain welding modes are provided, differing from each other in the technique of working, the position and speed of the electrode, and the amplitude of its movement.

Below we will consider the main methods for creating correct welds that ensure reliability and quality of the connection.

Types of welded joints

The classification of welded joints is quite extensive; they differ in the type and type of welding of parts.

Depending on the type of connection, welds can be single-sided or double-sided. The choice in favor of one or another type of connection is made depending on the technical parameters of the product being welded. As a rule, the most critical structures are welded using a double-sided seam, which ensures greater reliability of the connection.

Based on the type of connection, welds are divided into the following:

• butt
• T-bar
• corner
• overlap

Butt joints

This type of connection is quite often used for welding sheet metal structures and pipelines. A gap of 1-2 mm is established between the workpieces to be welded, and they themselves are fixed as rigidly as possible to avoid displacement. During the welding process, the gap is filled with molten metal.

Metal sheets up to 4 mm thick are welded with a one-sided seam without pre-treatment, with the exception of mandatory cleaning from corrosion.

When joining products with a thickness of over 4 mm, both one-sided and two-sided seams can be used. In these cases, preliminary cutting of the edges in the welding zone is carried out.

Butt welding of workpieces with a thickness of over 12 mm requires a mandatory double-sided weld, since one-sided welding cannot melt such a layer of metal. In this case, it is necessary to pre-cut the edges on both sides. If the design features of the workpiece do not allow for double-sided cutting of the edges, the seam is welded in several passes, filled with a multilayer weld.

Overlap welding

The overlap joint is suitable for welding metal workpieces up to 8 mm thick. When using this type of connection, welding is carried out on both sides to prevent moisture from entering and causing corrosion between the sheets.

To obtain a high-quality seam when overlapping welding, the electrode must be at an angle of 15 to 45 degrees to the working surface. If you deviate from these values, a significant part of the melt spreads away from the joint, which significantly reduces the strength of the joint.

Corner and T-joints

The operating technology for these types of connections is largely similar. T-joints in cross-section are similar to the letter T, and corner joints are similar to the letter G.

Depending on the thickness of the metal, T-joints can be welded in one or two seams, with or without preliminary cutting.

The requirements for welding fillet welds are the same as in the case of T-welds, since, in fact, the fillet weld is considered as part of the T-weld.

For a high-quality connection of corner or T-elements, the planes to be welded should be positioned at the same angle. It is optimal to weld them “into a boat”. When connecting parts of different thicknesses, the angle of inclination towards the thicker workpiece should be about 60 degrees. In this position, most of the heating will occur on the thick part, which will avoid through burning of the thin metal.

Spatial position of welds

In addition to the above types of connections, welds also differ in their spatial location.

The simplest and most comfortable for the welder is to work with connections created in the lower position. In this case, it is enough to simply control the direction of the seam and avoid spreading of the molten mass. As a rule, even a welder who does not have much experience and qualifications can handle seams welded in the lower position without much difficulty.

Other spatial positions of welds, such as vertical, horizontal and overhead, require certain technical training and sufficient qualifications. For high-quality welding of vertical, horizontal and ceiling seams, it is necessary to comply with the technological standards prescribed for a particular type of welding.

  Are electrodes a material or a tool?

How to weld a vertical seam correctly?

The difficulty of welding workpieces in a vertical position lies in the fact that the melt flows down under the influence of gravity without filling the seam. To avoid this, it is necessary to keep the end of the electrode closer to the weld pool, using a short arc. When working with some brands of electrodes, they can be supported on the part being welded.

Preliminary preparation of the edges of the elements to be welded should be carried out depending on the type of connection and the thickness of the parts. Next, the workpieces are fixed in the required position with tack welds that prevent the elements from moving.

A vertical seam can be welded correctly either from the bottom up or vice versa . A better quality seam is obtained by moving the electrode from bottom to top. Welding a seam from top to bottom requires careful monitoring of the weld pool, however, experienced welders using this work pattern can get good results.

For novice welders, when connecting vertical seams, welding with arc separation is acceptable. This method is simpler, since when the arc is torn off, the metal cools down without having time to flow down. The electrode movement pattern is standard - from side to side in loops or from bottom to top.

How to weld a horizontal seam correctly?

The technological regulations for this type of welded joint are in many ways similar to the previous one. To prevent the molten metal from flowing down, it is recommended to increase the speed of movement of the electrode, which reduces heating of the metal. In addition, you can briefly tear off the arc, allowing the metal to cool. Another method is to slightly reduce the welding current. To obtain a high-quality seam, one of the indicated methods should be used.

How to weld a ceiling seam correctly?

This type of welded joints is considered the most complex and requires high qualifications and skill of the performer. In order to properly weld a ceiling seam using electric welding, constant monitoring of the weld pool is necessary. When creating a joint, the welding electrode is held at right angles to the workpiece, creating a short but constant arc. The recommended pattern for guiding the electrode is circular movements, expanding the seam area.

Finishing of welds

As a rule, most welded joints require post-processing to remove splashed melt, scale, and slag. In addition, there is often a need to level the convex surface of the seam.

When cleaning a seam, first of all, using a hammer and chisel, splashes, scale and slag are removed from the surface of the seam. Next, if necessary, the seam is leveled using an angle grinder. The grain size of the abrasive wheel is selected depending on the required level of seam smoothness.

In some cases, the weld is coated with a thin layer of molten tin.

Traditional ceiling lighting is a chandelier in the middle of the room, but now there are various options for suspended ceilings.

Source: https://rem-serv.com/svarka-elektrodom-vertikalnyy-i-potolochnyy-shov/