How to weld profile pipes correctly

How to weld a square pipe correctly?

Profile pipe is a material for small work or small structures inside the yard. It is most often used to assemble greenhouses, make frames, fences and much more with your own hands.

It is not immediately clear how to weld profile pipes professionally. To understand the process, let's look at the variations of working with the profile.

How to weld profile pipes correctly?

For various types of structures, the following types of profiles are used:

There are others, but these are some of the popular ones. After all, there are also differences in cross-section.

Another thing is more important - the profile pipe is produced from carbon and low-alloy steel. It is not difficult to connect this material; there are the following technologies for welding a profile pipe:

• Electric arc.
• Gas welding of profile material.
• Contact.
• Inverter.

Each of them has its own characteristics. We read about this below.

Welding methods and methods

All known methods and devices for profile welding today. Let's list them by popularity.

Electric arc

This is the most convenient and popular method, performed using electrode pressure. The peculiarity is that with electric arc welding you can reach the most inaccessible places.

For your information! It is this method that allows you to work with any profile wall. Although the thinnest types of pipes require preliminary setup of the device.

When connecting a profile pipe, you need to acquire a welding machine and electrodes. Although it is more profitable to borrow from a neighbor. Also, any private welder must have a protective suit and special clamps for the profile.

Inverter

An improved type of electric arc welding. Just as reliable, simple and independent for private construction. The inverter device is convenient in everyday life and at work. The benefit is obvious: compact, light weight, affordable price.

It is important to understand that for beginners this is the most correct way. Because there is a pulse mode.

An inverter machine can weld profiles of any thickness. Welding of thin-walled profiles with an inverter is carried out at 50 A. By increasing the voltage, you can work with classic thickness.

Welding is carried out by exciting an electric arc and contacting the workpiece with an electrode. The consumable (electrode) begins to burn and covers the cleaned base. What’s interesting is that the electrode contains a composition that, when heated, prevents contact between atmospheric air and the working surface.

Visible advantages of the inverter:

1. No electrode sticking.
2. The constant current of the device maintains the stability of the arc, hence the quality of the seam. The product looks high quality without additional processing.
3. Contact welding provides a reliable connection that is resistant to stress.

Gas

Not the most common way. And it’s not about the equipment, but about the quality of the seam. Its mechanical properties leave much to be desired. Why is that?

Technically, a high temperature is created due to an oxygen gas flame. And the gaps between the parts are filled. It is important to understand that a dirty, uncleaned pipe does not form a seam.

Gas welding is performed with oxygen or acetylene. A burner is used for feeding.

It is gas that is easiest to weld thin parts of profile pipes.

But for any diameter it is necessary:

• Get wire that is the same in composition as the material.
• Flux. Necessary for less oxidation of steel.

There are two types of gas welding seams:

1. From right to left. For thin-walled profiles.
2. From left to right. Optimal for pipe walls thicker than 5 mm.

Contact

The best option for bad weather conditions due to the stable and high-quality seam. Performed strictly by specialists.

In a nutshell, masters cook using electric current. It heats the profile without filler materials, flux or wire.

Questions for professionals

It is worth noting that it is not prohibited to weld the profile at any desired (comfortable) angle. Also for profiled pipes there is an overlap connection, a joint to a joint, or a T-joint.

The formation of the seam is more important, and experienced welders recommend creating seams from the bottom position. When there are inconvenient areas, horizontal, vertical and ceiling positions are used.

Which electrodes are best for cooking?

Considering the grade of steel, in order to successfully weld a profile pipe with electrodes, we give preference to:

• AHO-4. One of the most common due to its versatility. No need to ignite, suitable for different types of equipment.
• MP-3С. For ideal seam quality and appearance.
• UONI-13/55. For professional welders.
• OZS-12. Optimal connecting seam. Lack of resistance to wet weather.

Which mode should I use?

We study the welding process. When setting the mode for manual welding equipment, we focus on the current strength. This is the most important indicator. It strictly corresponds to the diameters of the electrodes. And the electrode (electrode thickness), in turn, is selected to match the thickness of the profile wall.

Table with indicators to select the electrode diameter:

Butt welding

Otherwise called T-bar. Simple in appearance, but to perform it requires training. Butt welding requires:

1. Performing clamps at each corner of the section. Then it is necessary to correct the joining of the section, welding along the entire plane of the frame.
2. A thin profile is cooked in one go, a thick one will require several stages.
3. The arc is fed so that there is no metal subsidence. So that the edges have time to melt.
4. It should be completed with a reference to the edge. It necessarily coincides with the original one, which overlaps.

Welding a thin profile pipe

It is difficult to weld a thin pipe. For a thin profile pipe (its walls are 2-3 mm), it is more correct to choose an electrode of similar thickness with a diameter of 2-3 mm. If you have no experience, then it is not advisable to spoil the material.

It is better to entrust it to a qualified welder. He will set the required current strength and take suitable electrodes (ANO21 or MP3S).

For your information! It is optimal to connect a 2 mm profile with an inverter to avoid burn-through.

How to weld profile pipes at 90 degrees?

Before work, read the rules:

• We cut the blanks.
• We work on a flat plane (concrete).
• Temporarily fix the angle. Magnets and scarves will do.
• We cook steel in stages. From the very beginning, rough welding, then checking the geometry. Then there is the finishing high-quality seam.

When welding, the pipe ignites, what should I do?

To get the job done without this incident, we follow the rules:

1. Spot welding over short sections.
2. To avoid overheating, you can insert a massive metal block with a cross-section. It must be adjusted to the internal dimensions of the tube blank.
3. Reduce the distance between each edge.
4. Set the lowest output current mode.
5. Moving the electrode itself is faster.

welding lesson

How to properly and quickly weld a profile in various ways:

Joint welding. Let's watch the video instructions for a master without experience:

How much does it cost to hire a welder?

We focus on cost on the central region of the Russian Federation. It is important to understand that the work of a hired welder is measured in different quantities. Focus on:

• Centimeters (from 20 rubles per unit).
• Joints (from 150 rubles per joint).
• High cost for complex (inconvenient) designs. Gates and fences are already in linear meters (from 600 per linear meter).
• Hot welding method.

On any of the sites the price is always approximate. Discuss specific actions at the site. After which they issue an invoice. The welder not only makes the weld, but also the preparation. And this is a labor-intensive process.

Results

Theoretically, we delved into the essence of the seemingly simple work of welding corrugated pipes at home. We came to the conclusion that it is better to choose budget equipment, universal electrodes, for connecting with your own hands. It is important to practice on small useless sections before starting work. And only then start creating the design.

Source: https://tepliysezon.com/kak-pravilno-svarit-kvadratnuyu-trubu/

What electrodes should be used to weld a profile pipe?

Profile pipes have a number of advantages. They are convenient to use during installation due to their relatively low weight. They are convenient to weld and join due to the standardization of their production in size and shape, if you know which electrodes to weld the profile pipe with.

The walls of all profile pipe materials are characterized by uniform thickness and surface smoothness, which greatly simplifies the process of welding and installation. Special attention should be paid to which electrodes are best to use for welding profile pipes.

Machines for welding profile pipes

Any type of welding machine can be used to weld profile pipes. This is especially true for pipe materials with thin walls. To weld them, a large current is not required, so a unit operating at a current of 55 Amps is sufficient.

A separate point is the type of device used. It is recommended to use argon-arc and electric-arc units for welding. The transformer used in the device is important. The preferred option is an inverter type transformer. It makes it possible to use the pulse mode when welding.

Welding a profile pipe with an inverter

Not too stringent requirements are imposed on the welding mechanism holder. Considering the small diameter of the inserted electrode, almost any welding machine with any type of torch and holder can be used for welding.

Electrode welding and its features

When answering the question of which electrodes are best for welding a profile pipe, you need to decide on the type of welding used. There are three main types of welding:

• electric arc;
• gas;
• contact

Electric arc welding is used in most cases. A special feature of this type is that the electrodes, together with the welding unit, can work in hard-to-reach areas.

This type of welding is universal, as it can be used for any pipe materials with different thicknesses and cross-sections. The exception is pipes with a wall thickness of more than 4 mm. Before welding, they will require preliminary preparation. We are talking about a welded edge located at the end of the pipe.

"Note!

Welding of this type is carried out both overlapping and by T-joint and butt joints.”

Much depends on the use of the electrode when welding using the specified method. If microelectrodes for welding have a small cross-section, then a reverse polarity current with an average strength of 50 Amps is required.

Source: https://svarkaipayka.ru/material/elektrodyi/kakimi-elektrodami-varit-profilnuyu-trubu.html

How to weld a profile pipe

Profile pipes are much more often used for the manufacture of metal structures. They make the highest quality and most durable structures, regardless of their complexity. Welding profile pipes with your own hands is a complex and important procedure; to perform the work at a good level, you will need skills in working with welding - arc or gas.

Profile pipes made from selected grades have become more frequently welded than their plastic counterparts. The popularity of metal products is due to several factors:

• resistance to deformation;
• relative ease. A linear meter of profile pipes is lighter in weight for the same amount of all-metal products;
• dimensions. Pipe sizes are standardized, which simplifies the process of creating complex structures;
• relative ease of installation. Provided you have welding skills, pipes are easy to weld because they have smooth edges;
• durability;
• reliability;
• accessibility.

There are the following types of profile pipes:

• electric welded;
• cold-deformed electric welded;
• cold-formed seamless;
• hot-formed seamless.

The cross-section of each type of pipe differs from each other. So, for example, the electric welding manufacturing method allows you to make pipes with a wall thickness of up to 5 mm and a non-specialized thickness of up to 10 cm. The electric welding method is chosen if it is necessary to produce pipes with a wall thickness of 1-5 mm and an outer dimension of 1-10 cm.

The warm deformation method is used for pipes with an outer size of 6-18 cm and a wall thickness of 4-14 mm. But the products are deformed using the cold method to obtain a wall thickness of 1 to 8 mm and an outer size of 1-12 cm. In general, profile pipes are valued not because of their cross-sectional shape, but because of their cost-effectiveness and high strength, which these products are not deprived of.

Only the best steel is selected for profile pipes. Among the many varieties of this material, low-alloy and carbon are preferred. Manufacturers also make such products from stainless steel, but they are not so popular. Welding of profile pipes can be carried out only by common types of welding:

• contact;
• electric arc;
• gas.

Now we will look at each of the presented developments in more detail.

Arc welding

You have the opportunity to create any design, since it is possible to weld a profile pipe at any angle. Using this technology, it is easy to weld iron pipes with overlaps and T-joints.

Advice! Skilled welders advise making a seam on profile pipes in the lower position, but if it is necessary to connect these products in hard-to-reach places, then it is possible to use other types.

Mode selection

It is recommended to select a welding mode based on the following indicators:

• Current strength.
• type and polarity of current.
• The speed of the work being created (moving the electrode along the workpieces being welded).
• Electrode diameter.
• Arc voltage.
• Electrode tilt.

The current strength depends on the electrodes used. In order for the connection to be effective, you need to try to achieve the highest current strength. Do not forget that going beyond the permissible limit will reduce the quality of the seam.

Advice! How to weld a profile pipe so that the metal does not sag? Everything is the amount of additive; along with this, the edges of the products must be given time to melt.

For those who are using welding for the first time for such products, we would like to recommend working with thin-walled pipes with reverse polarity. Before working with thick-walled iron structures, it is necessary to first prepare the edges.

For high-quality fusion of products, it is necessary to cut them. Correctly and properly processed metal edges will not allow stress to grow, but it will be possible to apply a couple of seams. You need to cut the edges at 25–50 degrees. It is possible to select a more correct value after determining their welding thickness and product technology.

There are two types of electrodes - consumable and non-consumable. When working with the latter variety, filler wire is needed. Such a tandem provides a virtually perfect connection of products and, moreover, is very durable. It is possible to use such electrodes only in cases where the elements being connected have the same diameter.

What electrodes should be used to weld a profile pipe if the pipes being welded have the same diameter? The answer is simple: choose non-consumable electrodes, and in any other case - the second. The diameter of the electrodes is determined by the thickness of the walls of the elements being welded. It is fundamentally important to choose the correct current strength so that when working with narrow profile pipes you do not burn them.

Gas welding

How to weld a profile pipe using this technology? Gas welding is rarely used to connect such products, since it is impossible to weld correctly due to the poor mechanical properties of the purchased seam. This development involves heating the edges of profile pipes with an oxygen gas flame, after which it is possible to fill the gap that appears between the two elements.

Gas welding must be carried out along prepared edges, which are cleaned of dirt and cuts are made. A detailed video about this technology will be a clear example.

To cook using gas welding, you need acetylene and oxygen. For work you will need additional materials - flux and welding wire.

The first material must be the same as the profile pipe being welded, and the second is needed to reduce the degree of oxidation of the metal. The last component forms a narrow film on the edges of the pipes, which protects the metal.

Advice! To work with gas welding at home, you must have experience. Such equipment is explosive!

Gas welding can be carried out:

• From left to right. When choosing this technology, gas consumption is reduced to zero, and the work is done faster. Applying a weld according to this principle involves the use of an additive directly behind the burner itself, which makes it possible to weld thick-walled pipes.
• From right to left. This development is used for thin-walled profile products, because it makes it possible to obtain a neat seam. Here the additive is applied in front of the burner.

contact welding

The connection of products can be carried out under any climatic transformations. Resistance welding provides a reliable and high-quality seam, but only experts can work on this development. The principle of resistance welding: using a current, an electrode welds the edges of profile products. The joining of iron products occurs without any additives.

Profile pipes are high-quality and durable products. With high-quality welding, structures made from them will last a couple of decades. We have considered all possible developments for connecting profile products.

Source: https://uchebniksantehnika.ru/truby/kak-svarivat-profilnuiu-trubu.html

Methods and technologies for welding profile pipes: which electrodes to choose?

In the construction equipment market, profile pipes are considered a popular and sought-after product; they have replaced angles, beams and metal channels, since the structures are much lighter. Welding a profile pipe is practically no different from similar work on joining metal products, but requires a special selection of electrodes.

Design features, advantages, characteristics

Profile pipes of square section have high resistance to fracture and bending, while such products are 20-25% lighter, convenient for installation of any structures, due to the large contact area.

The main dimensions are regulated by GOST - these are the width, height, length of the profile, as well as wall thickness.

According to the manufacturing method, professional pipes are divided into three main categories:

1. Cold drawn with wall thickness in the range of 1-8 mm.
2. Hot rolled - 4-14 mm.
3. Sutures, made using welding - 1-5 mm.

The first two options do not have seams, so they can be used not only for the manufacture of openwork structures, but also for welding pipelines.

Advantages:

• easy installation;
• replacement of heavy elements from profile fittings due to lower cost;
• square and rectangular shape ensures easy loading and transportation, as well as storage in storage areas;
• high resistance to static loads, deformation and temperature fluctuations;
• With the help of profile pipes, non-standard architectural solutions are possible.

The technical characteristics of the product are interrelated, so when purchasing it is easy to evaluate the quality of the products offered by different manufacturers.

Connection methods and methods

Welding of professional pipes is carried out in several ways, which have their own characteristics, so let’s talk in detail about each.

Electric arc option

The great popularity of the method is explained by the following reasons: ease of use, quality of the seam joint, the ability to weld in hard-to-reach places, easy to find equipment and related materials in the retail chain. To work successfully you will need:

Electrodes are selected in relation to the wall thickness of the profile pipe, for example, if it is no more than 4 mm, then rods with a diameter of 2-3 mm are used.

Inverter

The equipment has compact dimensions and light weight, the cost is much higher than ordinary equipment, but the inverter quickly pays for itself and allows you to work at home, and the performer does not need to have the skills of a professional welder, since the product has a pulse mode.

It is easier to weld a profile pipe with a wall thickness of 2 mm using an inverter; the current varies in the range of 50-60 A. The voltage must be increased when connecting products with thicker walls. The arc burning is stable, there is no need to worry about the electrode sticking, since the equipment has a built-in system that eliminates such negative manifestations.

Using gas

The process is carried out using the following equipment:

• cylinders filled with acetylene and oxygen;
• reducers with pressure gauges that allow you to control gas flow;
• standard gas burner;
• gas supply hoses;
• wire with solder.

The connection is made by melting the edges and filling the gap between the parts with molten metal and solder.

Tips from professional welders

The profile is welded at any convenient angle, using all connection methods permitted by GOST.

What electrodes should I use?

Professional performers recommend using the following brands:

• ANO-4 is a common and universal brand, does not need to be calcined before use, suitable for working with a variety of welding equipment;
• MP-3S should be used when increased quality requirements are imposed on the seam;
• professionals use the brand UONI-13/55;
• good connection quality is provided by OZS-12 products, but they lack resistance to dampness.

These recommendations apply to profile pipes with dimensions of 20x40 mm.

Butt method

To carry out this welding mode, the following requirements exist:

• first, tack work is done at the corners of the structure, then the accuracy of the joining is checked, and then the joints are welded along the entire perimeter;
• products with thin walls are boiled in one go, and thick-walled ones - in several passes;
• the arc is conducted at such a speed that the metal does not sag, but the edges have time to melt.

The welding of one joint is completed in such a way that the edge of the seam coincides with the original one and is overlapped.

For thin-walled products

How to weld thin metal corrugated pipes with a 2 mm electrode - such rolled metal is a thin-walled type and is connected using electrodes with a diameter of 1.5 to 2 mm; performers with extensive experience are allowed to perform welding work. The current strength is not higher than 60 amperes, products of the MP-3S or ANO-21 brand are used. Beginning welders should weld thin-walled profiles using an inverter.

Right angle

To achieve an exact 90-degree angle when welding a profile, you must have experience and the appropriate auxiliary tools . There is such a methodology for carrying out work:

1. Profile pipes are cut into pieces of the required length.
2. All work is performed on a flat surface.
3. For reliable fixation, magnetic squares or improvised means are used.
4. The connection is carried out in stages with a mandatory check of the connection angle.

First, the products to be joined are tacked, then the angle is specified using a measuring tool; if everything is in order, then the profile is welded around the perimeter.

Elimination of burn-through

Such negative consequences of welding occur when connecting thin-walled profile pipes, in order to prevent burn-through of the metal, it is necessary to accurately select the diameter of the electrode and set the welding current to low values, and apply the reverse polarity. Similar defects appear due to the inexperience of the performer.

conclusions

Welding a profile pipe has some nuances: you need to accurately select electrodes depending on the wall thickness, and have sufficient experience in welding. It is better for beginners to train on corners and channels, since there the risk of warping or burning is much lower.

Source: https://svarka.guru/tehnika/detaley/profilnye-truby.html

How to weld profile pipes with your own hands

In private households, the issue of arranging your home is always relevant. If the owner is interested in a durable design, then installation will not be possible without the use of profile pipes. Examples of such structures include a fence, a canopy, the design of a lamp post, elements of a playground and much more. If you want to improve your site, the owner has a corresponding question: “How to weld profile pipes with your own hands?” Let's try to figure it out in this article.

When welding thin-walled elements, consider the following factors: welding is carried out with a current of 10 to 60 A; the diameter of the electrodes is 0.5-2 mm; the connection is performed in one pass; The quality of the seam directly depends on the welding speed; do not allow the working edges to cool down.

Products of any thickness are subject to deformation during welding to a greater extent than round ones; remember this when working. In a hot state, metal is capable of filling empty spaces: if the hollowness of the elements is important, make sure that there are no drops of metal left inside.

Welding Instructions

There are several welding technologies. The choice is justified by the circumstances and features of the structure being manufactured: manual, gas, automatic or semi-automatic, electric arc, contact/butt, powder. Let's look at the 3 most popular methods.

Manual arc method

Here you will need a welding machine, an inverter, a transformer, electrodes, devices for welding profile pipes, centralizers-clamps (the optimal solution for home craftsmen), and magnetic angles for connecting at the desired angle. For work you will need sandpaper for cleaning products, protective equipment, masks, and gloves.

The method is good for assortments of different sections. Products with walls more than 4 mm thick require preliminary preparation. Clean and degrease the ends before welding. Before work, pay attention to the choice of electrode: elements with a cross-section of less than 4 mm are welded with rods with a diameter of 2-3 mm and a current strength of 50-60 A. Thin-walled elements are welded with minimal gaps and without edges.

Gas method

The essence is to heat the edges with an oxygen gas flame, which leads to a gap between the parts of the structure. The gas used here is acetylene and oxygen. The method is inferior in functionality and quality to the classic manual method, but is well suited for thin-walled elements. In addition to gas, you will need a special wire, similar in composition to the main building material. The sequence of actions will be as follows:

1. The edges are prepared: the edges are cleaned of dirt, and the required shape is given in the form of a bevel.
2. After this, welding begins. The seam is made from right to left, as is done when working with thin-walled products. The burner with the flame should be directed towards the edges with the additive forward, then begin processing the edges.
3. When welding structures larger than 5 mm, the seam technique is used from left to right. It allows you to use gas economically. The burner is directed to the part of the seam to be joined.

Electric arc method

Allows you to connect elements at different angles. Most often, the seam is located in the lower position, but this depends on the volume of the walls of the structure and the characteristics of the connection. The seam positions can be horizontal, vertical, or ceiling. With the electric arc method, the connection occurs with a butt, overlap, corner, or T-joint.

1. When working, monitor the amount of additive, take breaks so that the edges of the parts to be joined are well melted. This is important to avoid metal subsidence.
2. Connect pipes with thin walls with reverse polarity, be sure to prepare the edges.
3. If the walls are more than 4 mm, do not forget about cutting the edges. This step will help to melt the metal completely and ensure a high-quality connection.

Where to buy rolled metal wholesale?

Metal warehouse "Stal-Invest" is a reliable supplier of large quantities of metal products. A full range of rolled metal products is always available in warehouses, including fittings and bent channels. We work with large manufacturing plants and offer low prices for batches of products. “Current prices” you can always find the current price list for each item in the catalog. To place an order, call the hotline listed on the website.

Source: https://stall-invest.ru/articles/svarka-profilnykh-trub/

How to weld a profile pipe correctly

In this article we will describe the main nuances that you need to know when welding profile pipes, as well as any similar rolled metal. There are main types of welding of profile pipes:

• Arc welding;
• Gas welding;
• Argon welding.

Arc welding

For electric welding you will need an inverter, an electrode and straight arms. What you need to know:

• 1) The diameter of the electrode must be selected depending on the thickness of the profile pipe. 30 Amperes of current are supplied to each 1 mm of electrode. So, 90 Amperes are supplied to an electrode with a diameter of 3 mm. For welding in a vertical position, it is necessary to reduce the current strength by 15%.
• 2) With or without a gap? For a profile pipe with a wall of 3 mm or less, it is better to weld with a tear, otherwise you risk burning through the pipe wall. For pipes with walls of 4 mm or more, welding can be done without tearing off. But we must not forget about the correct selection of working current and the diameter of the electrode used.
• 3) Moving the electrode during welding. The simplest and most reliable weld is obtained as a result of longitudinal translational movements during metal surfacing.

Argon welding

This method is used to connect thin-walled pipes. It is very important in this method to choose the right electrode with the right diameter. If the walls of the profile pipe are less than 2 mm, then you can use an electrode with a diameter of 1 to 1.5 mm; if the wall thickness is more than 2 mm, the electrode should be 1.6 mm in diameter. You also need to select the thickness of the welding wire. It will be directly proportional to the thickness of the pipe wall.

It is necessary to take into account some nuances of the process:

• The electrode should be located near the weld pool. This improves the quality of the weld.
• The welding wire and electrode can only move along the seam. No lateral movements.
• The filler material must be supplied gradually and without sudden changes to avoid splashing.

And do not forget one small detail - before any type of welding, it is necessary to thoroughly prepare the profile pipe - first thoroughly clean and degrease the welding areas.

Source: https://www.100met.ru/articles/kak-pravilno-varit-profilnuju-trubu.html

Products – Tekhmashholding – group of companies, official website

Profile pipes are most often used for the manufacture of metal structures. They make the most reliable and durable structures, regardless of their complexity. Welding profile pipes with your own hands is a complex and responsible procedure; to perform the work at a good level, you will need skills in working with welding - arc or gas. Profile pipes from selected brands have become more often welded than their plastic counterparts. The popularity of metal products is due to several factors:
• resistance to deformation effects;
• relative ease. A linear meter of profile pipes is lighter in weight than the same amount of all-metal products;
• dimensions. Pipe sizes are standardized, which simplifies the process of creating complex structures;
• relative ease of installation. Provided you have welding skills, pipes are easy to weld, because they have smooth edges;
• durability;
• reliability;
• accessibility.

Types of profile pipes

There are the following types of profile pipes:

• electric welded;
• cold-deformed electric welded;
• cold-formed seamless;
• hot-formed seamless.

The cross-section of each type of pipe differs from each other. For example, the electric welding manufacturing method allows you to make pipes with a wall thickness of up to 5 mm and a total thickness of up to 10 cm. The electric welding method is chosen if you need to make pipes with a wall thickness of 1-5 mm and an outer size of 1-10 cm.

The hot deformation method is used for pipes with an outer size of 6-18 cm and a wall thickness of 4-14 mm. But the products are deformed in a cold way to obtain a wall thickness of 1 to 8 mm and an outer size of 1-12 cm. In general, profile pipes are valued not because of their cross-sectional shape, but because of their high strength and cost-effectiveness, which these products are not deprived of.

Profile pipes

Only the best steel is selected for profile pipes. Among the many varieties of this material, low-alloy and carbon are preferred. Manufacturers also make such products from stainless steel, but they are not so popular. Welding of profile pipes can be carried out only by common types of welding:

• contact;
• electric arc;
• gas.

Welding

Now we will look at each of the presented technologies in more detail.

Which electrode to weld a 20x40 profile pipe

Welding machines are used in many cases. They are used during the laying of water pipes and sewer systems. Welding is also widely used in domestic conditions, when it is necessary to create a structure for a canopy, roof, or eliminate defects in the design of a car. In each of these options, a welding machine can solve the problem quickly and efficiently.

Welding a profile pipe with your own hands

Of particular importance in the use of welding are profile pipes, which often have to be connected using it. In most cases, this type of pipe is made of either stainless or carbon steel. Such metal products have several advantages in their application:

1. Large selection of types, shapes and sizes;
2. The mass of both a single pipe and entire structures is not large. This allows you to connect them in complex configurations without creating a significant load on the load-bearing elements;
3. You can select several standard types at once. This allows you to independently install the structure in the future.

The most important thing when independently fastening a profile pipe is the correct temperature. The fact is that the temperature conditions determine the quality with which the products will be welded. This indicator depends on the wall thickness of the workpiece. It should also be remembered that when making an end connection, the corners of the elements being welded have a high voltage.

How to weld a profile pipe using manual arc welding?

The characteristics and simplicity of using the metal of a profile pipe allows you to connect it to each other in a variety of ways - a joint, a T-type method, and also an overlap. The lower position of the seams is a priority when welding metal profile elements.

The welding mode is determined by the following criteria:

• Electrode movement speed;
• Arc voltage;
• Polarity (assuming constant current);
• Current strength.

The last of these criteria is determined by the cross-sectional value of the electrode used. Welding of a profile pipe will be performed correctly and reliably only in one case - if it is possible to achieve the maximum current allowed for the metal. When welding using the butt welding method, the arc should be drawn so that the edges melt and the metal itself does not sag as a result.

Machines for welding profile pipes

You can connect metal pipes using two main types of devices:

• Arc welding;
• Gas welding.

Each of them has its own advantages and disadvantages. It is generally accepted that gas welding is more universal in its application. It can handle a wide variety of tasks and different types of metal. But not everyone can afford this type of welding machine.

The more common type is conventional arc welding. Therefore, all that is required for successful fastening of profile pipes:

1. take into account the wall thickness of the product;
2. select the optimal electrode diameter;
3. set the correct voltage on the device.

What electrodes should be used to weld a profile pipe?

Since standard structural steel is used for the manufacture of profile pipes, you can use the standard, most common electrodes. For example, the OMA-2 brand is ideal for this purpose. The products of this brand include titanium concentrate and ferromanganese.

— Application of various electrodes:

Also, many experienced welders recommend using electrodes marked on the MT-2 packaging. They are usually used together with welding rectifiers. The main criterion for selection is a stable arc and uniform consumption of filler materials.

Welding a profile pipe: rules for forming a reliable connection

The basic rule for using arc welding is to correctly connect the elements and carefully fix them using the spot method. When all the products are in place and pressed tightly against each other, you just need to weld several points around the entire perimeter so that the structure does not fall apart.

After this, you can start scalding all the parts. The weld line is drawn smoothly. The filler material must be applied evenly. When using conventional electrodes, beginners can arc from side to side within a small range. Not all professionals use this approach, but for beginners the method is quite suitable.

The most important thing during this process is to form a neat roll from the material being processed. A straight weld line will be formed.

How to weld a profile pipe - your secrets

The first piece of advice would be to thoroughly clean the surfaces and, most importantly, to make a perfectly even cut of both sides that will be joined.

Experts with many years of experience always advise beginners to adhere to several basic points. Their effectiveness has been repeatedly applied in practice.

So, the main points of the connection, known only to the “experienced”:

• The main problem with inexperienced welders is that they forget to check the correctness of the entire structure. Always control the geometry of the metal. They often start to twist during welding. This is especially true for profile pipes.
• The quality of the seam and its reliability directly depend on the speed with which the elements are welded. The speed should be such that the specialist has time to fasten the products before the heated edge cools down.
• For profile pipes, propane-butane and acetylene torches are not used. Their temperature is too high.

We perform arc welding

Initially, you should bring the products into a specially prepared room. All ends of the pipes that will be connected are degreased. The chamfer remover is used only if the thickness of the profile pipe is more than 4 mm. After using this device, you can make a seam in several layers. It will be quite durable.

If the pipe thickness is less, one welding seam will be enough. All parts must be secured in a table specially designed for this purpose. If it is not there, then use the help of one or more people. Welding of the profile pipe will be carried out efficiently.

A certain thickness of the material, brand and cross-sectional thickness of the electrode sets the voltage with which the welding process must be performed.

The slag should be knocked down from time to time to avoid premature corrosion.

Electrode position options

We perform gas welding

After preparing and degreasing the surfaces, apply flux paste. It will prevent oxide from forming. It is important to adhere to a certain bevel angle of the edges. It is usually 30˚.

How to weld a profile pipe correctly? The answer is simple - by feeding the additive evenly from start to finish in front of the flame. The burner will gently melt materials and connect pipes.

Gas welding has a distinctive feature. If the wall thickness exceeds 6 mm, the burner is moved from side to side. Thus, the level of acetylene consumption is reduced. And the parts are more firmly attached to each other.

— Horizontal gas seam:

Electrode welding and its features

The main aspects of using arc welding are the correct current mode. The location of the seams is determined by the position of the electrodes during the welding process. In this case, it is necessary to tilt the electrode slightly towards the seam.

With constant practice, you can achieve excellent results and learn how to create one of three main types of seams:

1. Short;
2. Average;
3. Long.

Source: http://ooo-asteko.ru/kakim-elektrodom-varit-profilnuyu-trubu-20h40/

How to weld profile pipes using electric welding and what electrodes to use | mk-soyuz.rf

To create durable and lightweight structures from profile pipes, three welding methods are used: electric arc, contact, gas. Each has its own characteristics, disadvantages, advantages.

Rolled products can be connected at any angle, in any plane, without compromising the integrity of the profile or damaging the inner surface. When welding a profile pipe, it is necessary to take into account the wall thickness.

Features and characteristics of profile pipes

Hollow rolled products of various profiles are produced from low-carbon or low-alloy steels. According to the cross-section, the profile is divided into:

• oval,
• flat-oval,
• multifaceted,
• rectangular,
• square.

The most popular is the square pipe due to its evenly distributed stiffening ribs and ease of installation. It is used to make stair railings, street structures, gate frames, greenhouses, and elements of the urban environment: gazebos, benches, and play equipment. Hollow rolled steel with a low specific gravity is characterized by great strength; metal structures can withstand large dynamic and static loads if the joint is made well.

Types of welding joints of profile pipes

The choice of method and temperature regime is determined by the thickness of the pipe walls, since the deformation stress of the profile is higher, this is especially true for end fastening; it is important that the structure does not collapse.

Welding methods:

1. Arc, used for rolling with a wall from 2 to 6 mm.
2. Gas, not used for thin-walled rolled products due to the rapid melting of steel with subsequent deformation.
3. Contact, requires special equipment.

How to weld a profile pipe correctly? — Machine tools, welding, metalworking

Welding machines are used in many cases. They are used during the laying of water pipes and sewer systems. Welding is also widely used in domestic conditions, when it is necessary to create a structure for a canopy, roof, or eliminate defects in the design of a car. In each of these options, a welding machine can solve the problem quickly and efficiently.

Features and types of profile pipe welding

Rolled metal uses not only round-shaped parts. Modern products of square, rectangular, and oval shapes are also widely used. They are called “profile pipes” and are most often made of steel.

Profiled pipes are used mainly for water supply and sewerage systems. Welding a profile pipe, contrary to popular belief, is not a very difficult task. This process is not much more complicated than soldering polypropylene.

Profile welding is characterized by the following features:

1. Reasonable price. Of course, the price for profile pipes will be higher than for analogues made of polypropylene or HDPE. But the difference is small.
2. They are practically not subject to deformation.
3. These parts are not much heavier than plastic ones.
4. Welding square pipes gives the best results and is a guarantee of the durability of the structure.
5. In the process of welding profile pipes, you can install the system that you personally need. Despite how complex and unusual it is.

Types of the most popular profile types

• Cold-deformed, electric welded. These are pipes that, after electric welding, have undergone cold deformation.
• Cold-formed and hot-formed, seamless. A cold-formed seamless pipe is a part without a seam. Its size is predetermined and formed by cold deformation. Seamless hot steel parts are produced by hot and cold rolling methods, as well as by sending and non- sending drawing.
• Electric-welded, that is, straight-seam pipes made of carbon and non-alloy steel.

Profile parts can also be divided into types depending on the type of section: square, rectangular, oval, multifaceted, and so on.

Welding of square pipes can be carried out using the following methods.

• Elektrodugov
• Gas
• Contact

Below we will look at each method in more detail.

Electric arc method: which electrodes are best for welding a profile pipe?

The steel profile can be “cooked” at the angle you need. The joining method can be T-joint, butt joint or lap joint. Most welders know how to weld a steel profile: the weld must be made in the down position. In this case it is the most convenient. If you are dealing with connecting elements in a hard-to-reach place, you can also use vertical and ceiling methods for making a seam.

Main indicators of the welding process mode:

• Voltage
• Welding electrode speed
• Polarity when using DC current
• Current strength

The last indicator is very important. Welding of square pipes must be carried out at the maximum permissible current value. Only in this case will the product be of the most durable and high quality.

In each specific situation, the welder must be able to determine this maximum permissible value, and in no case exceed it. Otherwise, the quality of the seam will deteriorate.

Most novice specialists ask questions about which electrode to weld a 20x40 profile pipe and which electrodes for welding a profile pipe with an inverter are better to buy: high cost or cheaper? All electrodes are divided into consumable and non-consumable.

The latter option is used in tandem with filler material - wire. In this case, the seam is as smooth and durable as possible. These electrodes can only be used when connecting elements with the same diameter.

Consumable electrodes are used in all other cases.

You should know that the diameter of the required electrode depends on the thickness of the metal of the part being welded. Welding of thin-walled pipes, for example, 1.5 mm thick, is performed with electrodes with a diameter of up to 2 mm. Do not forget to adjust the welding current: it should not be too high so as not to burn the steel. Welding of thin-walled pipes is performed with reverse polarity. This is due to the possibility of burning through thin material.

The edges of a thick-walled product (more than 4 mm) require careful preparation before joining.

Stainless steel is used very rarely for the manufacture of profile pipes. Special electrodes are used especially for this type of material.

How to weld a frame from a profile pipe is shown in the video below.

Gas connection method

This profile connection option is less common. The seam with a gas connection is not as high quality as when using an electric arc. The preparation of the edges of the parts must also be carried out very carefully. This type of welding process uses oxygen and acetylene. The gas method is recommended for products of small thickness.

To carry out gas welding, you need to purchase a special wire that is similar in composition to the parts being welded. It is also necessary to purchase flux, which protects the metal from the negative effects of air by forming a special film on the surface of the seam.

Techniques for making a seam using a gas machine:

1. From left to right. Used for thick materials more than 5 mm, guarantees minimal gas consumption and high productivity.
2. From right to left. Performed for thin metal walls, it allows you to make a high-quality and neat seam.

Contact method

This type of connection is performed only by highly qualified specialists who have a certain level of experience and training. It is almost impossible to do it yourself. The basic principle of this type of connection is that the profile elements are heated by electric current without the use of any special filler materials.

Thus, welding a profile pipe is a fairly simple process that can be carried out even independently if you follow certain rules, procedures, and also follow the tips indicated in this article.

Obviously, the simplest and most common connection method in this case is electric arc. It allows you to “cook” the profile at the angle you need. The contact method is performed only by professionals. It should also be noted that with any joining method, the most important role is played by the metal preparation stage.

If it is carried out with insufficient care and thoroughness, the quality of the seam will decrease.

Source: https://svarkaed.ru/svarka/izdeliya-i-konstruktsii/osobennosti-i-raznovidnosti-svarki-profilnoj-truby.html

DIY copper pipeline - Metals, equipment, instructions

The unique performance qualities of copper have ensured that pipe products made from it, despite their high cost, have been widely used.

Copper pipes are not afraid of ultraviolet rays, have a low coefficient of thermal expansion, and high corrosion resistance in non-acidic environments.

The ability of copper to maintain ductility at subzero temperatures makes it possible to install copper pipes even in winter conditions. The durability of copper pipes does not depend on the temperature and pressure of the media transported through them.

Copper pipes make it possible to transport high-temperature liquids in them.

Applications of copper pipes

Installation of copper pipes in heating systems is possible due to their high resistance when working with high-temperature liquids. This property is especially relevant for a single-pipe heating scheme, in which to ensure the coolant temperature in the last radiator is about 70ºC, it is necessary that in the first it is equal to approximately 120ºC

Connecting pipes with compression fittings does not provide an absolute guarantee of reliability and requires constant monitoring during operation.

The maximum temperature that polymers used in heating systems can withstand does not exceed 95ºC, and media with temperatures up to 300ºC can be transported through copper pipes.

An important property of a pipeline made of this metal is its ability to withstand pressure of 200-400 atm, while the soldered connection of copper pipes, made by hand, remains sealed.

At the same time, metal-plastic products can withstand, on average, a pressure of 6 atm with a possible operating pressure in the system of 6 - 8 atm. Heating pipes made of soft copper can easily withstand 3-4 freeze-thaw cycles.

Thanks to its antibacterial properties, copper can resist the infiltration of contaminants in urban water supplies. Plumbing copper is resistant to chlorine.

Moreover, chlorine, being a strong oxidizing agent, promotes the formation of a protective oxide film on copper, which extends the service life of the pipeline.

However, it should be remembered that hidden laying of copper pipes with your own hands can only be done if there is a polymer shell on the pipes, which protects the copper from stray currents.

When using copper pipes in heating and water supply systems, the combination of different materials in the system, which leads to local electrochemical corrosion, should be avoided. If it is necessary to connect, for example, aluminum with copper, brass transition elements are used.

Copper pipes are universal: in addition to water supply and heating systems, they are used to transfer gases and refrigerants in refrigeration systems, and are used in air conditioning systems.

Connecting pipes with compression fittings

Before installation, ensure that there are no burrs, cracks or other damage on the pipe ends. This will help avoid problems in the future operation of the pipes.

To connect copper pipes with your own hands, use crimp or solder fittings - connecting parts of various shapes and purposes.

Compression fittings are made from brass and have a crimp ring inside them to ensure a tight fit. The ring is tightened by hand using a wrench.

However, it is advisable to use such fittings only in places where it is impossible to carry out work with open fire and it is possible to easily check the tightness of the connection.

Compression fitting connections are designed for lower permissible pressures than solder fittings and must be periodically checked and tightened.

The connection of steel and plastic heating and water supply pipes with copper pipes is often carried out using compression fittings.

The nut is tightened using a wrench by a number of turns depending on the diameter of the pipe and determined by the fitting’s passport data.

Connections with compression fittings are not absolutely reliable and require constant monitoring during operation.

Capillary soldering method

Before you begin laying the water supply, you need to cut the copper pipes to the required sizes.

This method of soldering copper pipes is based on the capillary effect, which promotes uniform distribution of solder over the entire cross-section, regardless of the position of the pipe. To create a capillary effect, special fittings are used, the diameters of which must differ from the diameters of the pipe by a strictly defined value. For soldering over an open fire, a gap of 0.1-0.15 mm is recommended.

Connections using capillary soldering are carried out using special fluxes and solders - thin wires made of metal alloys with a low melting point, usually tin with small additions of copper and silver.

Solder joints are used in cases where the installation of heating or water supply pipes is done by hand in the floor or walls, or in other cases when visual inspection of the integrity of the joints is impossible.

There are two soldering methods: high temperature and low temperature.

High-temperature soldering, otherwise known as hard soldering, is used where the operating conditions of copper pipelines involve high temperatures. Such soldering is carried out using special fluxes and hard solders. For do-it-yourself pipeline installation, this type of soldering is practically not used.

Low-temperature, or soft, soldering is used for pipelines used for transporting liquid and gaseous media, the operating temperature of which does not exceed 110ºC. When doing low-temperature soldering with your own hands, the joints are heated to a temperature of approximately 300ºC.

Copper pipe soldering process

The time needed to solder copper pipes will be helped by markings on the fitting itself with recommendations for the required solder size.

Before soldering begins, the outer part of the pipe end and the inner fitting are sanded to bare metal. Next, a thin layer of solder paste or flux is applied to the cleaned end of the pipe. These materials, in a molten state, dissolve oxide films on the elements being connected, protecting their surfaces from further oxidation, which is caused by high temperatures.

However, given the fact that flux destroys the surface of the metal, when soldering with your own hands, it must be applied just before starting work and only on the area that will go into the fitting. After hardening, the flux forms a film that does not require removal.

Next, the pipe is inserted into the socket of the capillary fitting until it stops. The junctions of pipes and fittings are evenly heated with the flame of a gas burner or a hot air gun. For this purpose, it is advisable to use a lamp equipped with two burners or nozzles with sprayers.

If the flux used contains tin, then when it is heated to the required temperature, silvery drops will appear. In other cases, you can make sure that the desired temperature has been achieved by touching the solder to the heated surface - the solder should spread.

The molten solder must be injected into the joint immediately. Moreover, it does not matter at all from which side it will be introduced. Thanks to capillary action, the solder will evenly fill the entire joint.

Remains of flux from the fitting are removed using a rag.

The use of a variety of fittings in which the manufacturer has applied a bead of solder of the required size inside will help reduce soldering time. The fitting is placed on a pipe coated with flux and heated with a torch or hot air gun until the solder becomes liquid. After cooling, the water supply and heating pipeline structure is ready for operation.

Installation of copper pipes

In the process of installing plumbing systems with your own hands, it often becomes necessary to connect copper pipes with products made from other materials.

In heating systems, cold and hot water supply, copper connections with steel, plastic and brass are safe from the point of view of corrosion processes.

But the contact of copper with galvanized steel is dangerous for galvanized pipes and leads to their destruction due to electrolytic processes. To avoid pipeline failure, the connection must be made using brass fittings, and the water flow must be directed from steel to copper.

Before starting work, it is necessary to prepare a tool for installing copper pipes of a heating system or hot or cold water supply. To do this you will need: a pipe cutter or a hacksaw for metal, a file or scraper, and if there are areas of complex configuration - a pipe bender, a gas torch or a hot air gun.

Laying a copper pipeline with your own hands begins with cutting the pipe into sections of a pre-calculated length.

Then it is necessary to clean the outer and inner parts of the pipe from burrs, and if necessary, level the cut.

If the diameters of the pipes do not exceed 15 mm, then their bending radius should be at least 3.5 diameters, and if more than 15 mm, then four diameters. When bending by hand, a high-quality bend can be obtained only with a radius equal to 8 diameters.

Despite their resistance to corrosion, copper pipes, due to violations of manufacturing technology, improper soldering and severe contamination of water with abrasive inclusions, can be subject to very dangerous pitting corrosion. The pipe corrodes where the oxide film is destroyed. One way to avoid this process is to install filters on water supply and heating pipelines.

In the modern construction market, copper pipes, due to their unique performance qualities, quite successfully compete with products made from steel, plastic and metal-plastic, despite their high cost.

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