How to make an arc from a profile pipe. How to bend a profile pipe for a greenhouse: the simplest methods and rules for making blanks. The main methods of bending a profile pipe

Recently, it occurred to me to make a gazebo at a summer cottage out of rolled metal, and not simple, but with fashionable frills and bends to show off to friends and acquaintances and surprise them with something. For this, bent parts were needed, but I didn’t bring a pipe bender from the city and didn’t want to go after it (I already took a little cognac for mood). Therefore, I had to get out of the situation and decide how to bend the profile pipe at home.

Features of bending profile pipes

If you recently began to do something around the house with your own hands, you may not understand the importance of the problem. Indeed, what is difficult there: rot it to yourself with a hammer in any direction and that's it.

However, it is not so easy to give a profiled pipe a smooth and curved configuration, while retaining all its technical characteristics. This is usually done with a special tool under pressure in a cold or hot way.

The bottom line is that two forces simultaneously act on a rectangular profile when bending:

• compression - from the inside;
• stretching - from the outside.

As a result, several difficulties arise, due to which the locksmith comes up with various tricks for bending pipes:

1. Rolled metal in the process of mechanical action can change its shape, as well as lose the alignment of individual parts. As a result, the edges of the part will lie in different planes, which will not allow it to be used during installation.
2. The outer wall, which is stretched during the bending process, may not withstand the mechanical load and crack, losing the necessary strength.
3. The inner wall, on the contrary, will contract incorrectly and form folds, resembling a corrugated pipe in their appearance.

In principle, I have met more than once with cases when an incorrectly bent workpiece is simply crushed, after which it can only be thrown into scrap metal. This leads to an unjustified increase in construction costs, which is similar to death for a zealous owner.

That is why you should not immediately rush into battle with pipe cuts, but study pipe bending technologies. And they, by the way, directly depend on the technical characteristics of the rolled products used. I want to talk about this further so that you understand the whole mechanics of the process.

Influence of material characteristics on the choice of bending method

If you do not know yet, then I inform you that the concept of "profile pipe" includes pipes of all geometric shapes, including round ones. But for ease of understanding, it is customary to call only products of the following forms:

• square;
• rectangular;
• oval;
• flat oval.

This is due to the fact that a metal round pipe is used to design water and gas transmission systems, as it is ideal for this and has strong walls that can withstand significant pressure well.

Pipes of other shapes are more used in construction to create various structures and design furnishings. Further, I will only talk about square pipes, since I am going to use them for construction.

So, there are also many square pipes in the store. They differ from each other in cross section and wall thickness. And these two parameters, in turn, affect the minimum angle at which square rolled metal can be bent without damaging it.

I do not want and will not now go into engineering subtleties and features that home craftsmen do not need for nothing. I can only say that in order to determine the minimum bending radius, you need to know the cross section of the pipe.

The radius is defined like this:

• for thin pipes, the cross section of which does not exceed 20 mm, the pipe must be bent in a section 2.5 times greater than the height of the profile;
• for thick pipes, bending must be done in a section 3.5 times larger, otherwise the metal will crack on the outside or wrinkle on the inside.

For wall thickness. Personally, I do not advise bending large pipes with too thin walls, otherwise the parts will lose alignment.
It is better to use a grinder and a welding machine.

Before bending a profile pipe, it will be useful to know that the carbon steel pipes you use tend to spring back a little, that is, return to shape after the impact stops. Therefore, in order to bend the pipe under the desired radius, plasticity must be taken into account, making the bend a little larger than necessary according to the drawing or pattern.

Pipe bending methods

In general, I decided that it’s enough to load your heads with theory (although you can’t do without it). Therefore, I will go directly to how to bend a profile pipe at home.

Quite often in my practice, I bent profile pipes, while heating the bend with a blowtorch. High temperature increases the plasticity of the material and reduces the risk of damage to the part.

But if for construction you use thin rolled metal of a small section, you do not need to resort to additional tricks. Square pipes and so will take the shape you need. Of course, if you approach this matter with due skill.

I cannot give you unambiguous advice on when to use heat and when not. I can only say that the current building regulations provide that it is necessary to heat a round (not square) pipe if its diameter exceeds 10 cm.

However, I will give my own considerations, which have developed as a result of many years of work at construction sites:

• if the pipe section does not exceed 1 cm, I would not even mention any heating;
• in cases where the pipe cross section is more than 4 cm, I would still advise using a blowtorch so as not to spoil expensive rolled metal;
• between the two extremes above, decide for yourself.

You can try to bend the pipe by holding one end in a vise. If, when applying force, the pipe bends easily and does not wrinkle, you can not heat it. If it's hard to bend, warm it up. I'll tell you about that, and about that way.

Hot bending of profiled pipes

I'll start with hot bending, as more difficult. To avoid deformation of the pipe, its cavity must be filled with sand. In this case, you will get a detail, the appearance of which will satisfy even the most strict OTC master (inspired from the past).

The process of hot bending of a profiled pipe is as follows:

1. From suitable pieces of wood (I take two blocks) I grind out two plugs that are suitable in size for the existing pipe. They should fit snugly into the side holes of the part and not hang out.
2. Then, on the side of the plugs, I select small grooves through which hot gases and a bent metal pipe will be vented to the outside.
3. The section that will be bent is pre-annealed.
4. Then I prepare the filler, the role of which is played by pure river sand (although, in principle, any fine-grained sand can be used).

Sand is poured into the pipe according to the following scheme:

• I plug one end of the pipe with a cork;
• I pre-calcined the sand with a blowtorch;
• I pour sand into a workpiece installed perpendicular to the ground or at an angle;
• while falling asleep, I tap on the pipe so that the grains of sand are distributed evenly, leaving no voids;
• after the blank is completely filled, I close the second end of the pipe with a cork.

I recommend sifting sand before use, getting rid of gravel and small pebbles. First you need to use a large sieve, and then a fine one, with a mesh size of 0.7 mm, to get rid of dusty particles.
If this is not done, the sand will bake inside the pipe and it will be problematic to pour it out from there.

1. After filling the filler, I turn to bending. To do this, I clamp the workpiece with one end in a vice and mark with chalk the place that will need to be bent. The part must be fixed so that the weld seam of the pipe (if it is not seamless) is on the side. Otherwise, it may burst.
2. With a blowtorch, I heat the desired area to a dark cherry color and give the pipe the desired shape. This should be done with a quick but smooth movement, making sure that the bending is done in the same plane.

1. After the metal cools down, I knock out the plugs and pour the sand out of the pipes. If the wooden bars cannot be knocked out, I burn them out with a blowtorch.

I will immediately warn you that this method is suitable if you need to bend the workpiece under a certain (not very large) radius in one place. That is, the metal will have to be heated only once.

Otherwise, constant temperature fluctuations will violate the strength of rolled metal and the part may simply burst.

Cold bending

It is possible to bend a profiled pipe without heating it with or without filler. If the section of the part does not exceed 10 mm, you can do without filling the cavity. It is better to pour sand into a large pipe.

Sometimes profiled pipes I bent using a dense spring of the right size. It is placed in the cavity of the pipe, after which it is bent at the desired angle, without fear of displacement of the axes of the part.

In this case, it is important to choose the correct spring size. It should enter the pipe tightly, but move freely. Otherwise, then this part may not be available.

If you need to bend the pipe to the desired radius, and there is no blowtorch at hand, I suggest using another method, which I also had to resort to. To implement it, you will need a grinder with a disc for cutting metal and a welding machine.

The scheme of work is as follows:

1. It is necessary to calculate in advance the radius of the bend of the pipe and the segment that will be bent.
2. Cuts should be made along the length of this section on one side, leaving one side of the pipe intact. The number of these cuts depends on how small the bend radius needs to be.
3. After that, thanks to the resulting cuts, you can easily bend the part by holding one end of it in a vice.
4. The next step is welding the damaged areas using an electric or gas welding machine.
5. Once the seams have cooled, they can be cleaned and welded.

Use of special equipment

All of the methods described above can be used if there is a small amount of work to be done. However, when giving a smooth bend to a large number of parts, you will have to use specialized equipment. You can make your own, buy or rent.

I’ll tell you about this in a little more detail, since there are quite a lot of questions of this kind, so I consider the topic relevant.

The simplest manual pipe benders

At one time, I had to bend a considerable amount of rolled metal, so even offhand I can give many examples of simple bending devices. As I said, the specific mechanism depends on the pipe section, wall thickness and the required bending radius.

For home craftsmen who have decided to build an arched structure from profiled pipes, I offer the following options:

1. Thin profiled pipes can be bent using a horizontal steel plate with drilled holes. Pins are inserted into them, which play the role of stops when giving the workpiece the desired shape.

It is necessary to place the pipe between the stops and bend it at the desired angle. You need to start from the middle of the part and move to the edges. As a result, it is possible to bend the pipe, but you will not achieve the ideal shape, and you will have to apply a lot of force.

1. I recommend bending pipes of medium thickness with the help of rollers interconnected like a Volnov machine. In this case, the part must be fixed in a vice, and then the workpiece must be bent using special rollers.
   The quality of the bend is better than the technology described in the first paragraph. However, given the thickness and cross section of the workpiece, you need to be a strong athlete to bend the parts. Especially if there are a lot of them.

1. To bend parts under a small radius (for example, arches for a gazebo), you can use home-made patterns with a groove at the end and a collar for which the pipe is hooked.

As in all previous cases, bending requires considerable physical effort. But the part takes the ideal shape, due to the configuration of the sample.

bending plate

If you like DIY and often use shaped pipes, I recommend taking the time to make a stationary bending plate that will help you bend any square and rectangular pipes to the desired angle.

It may take the form of a mobile panel, which is attached to the work surface with clamps for work. Also, the slab can be welded to a channel or rail, concreted into the floor of the workshop.

The scheme for manufacturing a universal bending plate is as follows:

1. The basis for the fixture will be a thick metal plate. It is better to take thicker metal so that the device does not deform when bending thick pipes of large cross section.
2. It is necessary to cut or drill several holes in the plate, where to insert the bolts, which will serve as stops for bending the pipes at the desired angle.
3. The bending radius of the pipe during operation can be adjusted with nozzles of a suitable diameter, which are put on the bolts.
4. To maintain the alignment of the workpieces while working on them, you can install another plate that prevents the part from bending in a different plane.

Mandrel for pipe bending

This locksmith fixture is used to process pipes whose cross section does not exceed 2.5 cm. To make it, you will need a workbench and a large free space around it. On one edge of the working surface of the workbench, you need to drill a lot of holes in different places, which are necessary to secure the support bolts.

In addition, you will need a piece of thick plywood, along which the workpiece will be bent. The shape of the part after processing will exactly match the diameter along which the plywood was cut.

The disadvantage of this solution is that you need to change the template every time you need to bend the pipe to a different radius.

The scheme of work with such a mandrel is as simple as possible:

1. The end of the pipe is fixed between the bolt and the mandrel (pattern), which, in turn, is tightly attached to the workbench using several clamps.
2. After that, you just need to bend the pipe, resting it on the pattern.
3. If the workpiece is short, a pipe of a larger section (or diameter) can be put on its end, which will play the role of a lever.

Manual bending machine

If you are going to open your own business for the manufacture of arched structures from profile pipes, all manual fixtures will not suit you. After a few days of work, your hands will simply fall off, so it’s better to mechanize the whole process right away.

For bending pipes, in this case, it is better to use a home-made or purchased bending machine, consisting of two fixed and one movable roller. By adjusting the position of the latter, you can change the bending radius of a square or rectangular pipe. Although the price of the machine is rather big, it will save you a huge amount of time and effort.

Conclusion

Now, I hope you understand how to bend a profile pipe without a pipe bender and using special equipment. As you can see, if you know some secrets and technologies, there is nothing complicated in this process. You can safely get to work.

And if you have your own technologies for bending square or rectangular pipes, I will be very grateful if you share them in the comments.

You can get more creative ideas regarding the construction of houses and the arrangement of suburban land plots from the video in this article.

If you want to express gratitude, add a clarification or objection, ask the author something - add a comment or say thanks!

Many home craftsmen do not know how to bend a profile pipe on their own, without contacting specialists in workshops. In fact, it is not so difficult to perform such an operation if you acquire the necessary equipment.

1 Do-it-yourself profile pipe bending - practical advice

Thousands of owners of plots outside the city and private housing construction literally put their souls into their real estate. They try by all means to give it an original appearance. Moreover, such people strive to perform many landscaping operations with their own hands, truly proud of their work.

Very often, when arranging a country "estate", a person needs to bend a profile pipe, which is now very actively used for various purposes, from the construction of fences to the installation of an unusual visor over the entrance to the house. It is difficult, and sometimes simply unrealistic, to bend the pipe manually without using special devices designed for such purposes.

This statement is especially true for profile pipe products. If a round pipe can still be heated, wrapped around a special template, securely fixed one of the ends of the structure, and then try to bend it at the required angle, then this method is absolutely not suitable for profile products.

There is only one way out: to adopt a device for bending a profile, to study the principle of performing an operation with its help, and to solve the problem of giving the pipe the desired configuration. Note that even with the help of special equipment, it will not be easy to carry out such a procedure - it is highly likely that under the hands of an inexperienced person the pipe will flatten or its section will deform.

To minimize the risk of such an unfavorable development of events, it is recommended to pre-freeze the pipe by placing it in a large industrial-type refrigeration unit. If there is no large-sized refrigerator, it is recommended to perform the bending operation in winter, when the temperature is below freezing outside.

Before freezing, one edge of the profile product should be securely plugged, then fill the pipe with plain water and close the other end of the structure. After that, we place the workpiece in the chamber or take it out into the cold, wait until the liquid in it is completely frozen. Frozen water will not allow the product to deform in the process of bending it. And the process itself, believe me, will go much easier.

An alternative to the described method is a technology in which sand is poured into the pipe, plugs are placed at both ends of the structure, then 2–3 holes of small diameter are made in it. They are necessary so that subsequently, when the workpiece is heated, the gases formed in the pipe have an outlet. If holes are not made, there is a risk of deformation of the structure.

After completing all these operations, you can start bending. To do this, using a blowtorch, you need to heat the selected zone along which the bend will be carried out, and then boldly bend the pipe. The described preliminary steps (freezing, filling with sand, heating the profile product) will not have to be done when you use modern pipe benders designed specifically for working with pipes.

2 How to bend a profile pipe with a pipe bender?

Such a device is understood as special devices of several types, which make it possible, with a minimum of manual effort, to bend structures made of round or profile rolled products (for example, for home greenhouses and greenhouses, sheds, and so on). All pipe benders are usually divided into two large groups:

• Roller (they are also often called profile benders): they are used for bending profiled tubular products along smooth radii. In this case, bending is carried out according to the principle of pipe rolling.
• Hydraulic lever: with their help, metal structures are usually bent at the required angle, applying a certain force in a given place. The ease of the procedure is ensured by the fact that the force is set by the lever.

The advantages of using pipe benders are as follows:

• reduction of human effort to perform bending (manual labor when using a device with an electric drive is completely reduced to zero);
• refusal to install additional fittings and carry out welding work during the installation of pipelines);
• lack of flattening and creases (the metal retains all its technical characteristics);
• guarantee of obtaining curved pipes with the most accurate dimensions.

In addition, tube benders provide a truly elegant appearance to structures that are made from one-piece tubular products. From the point of view of decorative attractiveness, such designs can be considered impeccable. Try to achieve similar results if you do not know how to bend a profile pipe with a pipe bender. You are unlikely to succeed.

The choice of a specific pipe bending machine depends on the material of the products, as well as on the type of work that you will carry out using steel or (as you yourself understand, there is no need to bend plastic structures with a pipe bender). For example, copper pipes for installing a heating system or water supply are bent with a simple manual pipe bender, which is designed specifically for this material.

But already metal products for plumbing work are bent using a device that can cope with more durable and harder material. With profile pipes, of course, they work exclusively with a roller device, which was created specifically for such events. By the way, it also makes it possible to bend round seamless pipes with thick walls.

3 Popular models of domestic manual profile benders

In hardware stores, you can easily find different types of foreign-made pipe benders. But their price often does not suit the Russians, who prefer to buy proven domestic mechanisms. Fortunately, in terms of their capabilities, they are no worse than imported products.

The most popular devices for bending profile products are manual machines "PG-1" and "PG-2". The first one costs no more than $500, it is made in a compact form, being a mobile (portable) equipment. Due to this, the mechanism can be used directly at the installation site for bending copper, metal and with dimensions not exceeding 40 by 40 millimeters.

Structurally, the fixture is a frame with three rollers mounted on it. The pressure roller (it is central) allows you to pull the pipe. The ease of turning this roller is due to the presence of a comfortable handle. The width of the rotating components of the machine can be changed to work with pipes of different sizes.

The profile bender "PG-2" differs from its counterpart in a more powerful design. It easily bends pipes from the materials mentioned above with dimensions of 30 by 60 millimeters. With it, it is even possible to bend pipes into rings. It is clear that the cost of such a model is higher. You can buy it for 750-800 dollars.

We hope that you now have no questions about how to bend a profile pipe.

It is quite possible to bend a pipe from a profile on its own and without the help of rather expensive machines. Therefore, if you have a need to bend a pipe, then a special article on the site will allow you to learn how to bend a profile pipe at home without a pipe bender.

Bending a pipe with a grinder

In order to bend the profile pipe, you will need to use a grinder and a welding machine. Below we describe the details of such a process.

• Before starting this work, the pipe should be fixed (using a vise). This procedure is needed to find the product in the same plane. If there is a weld seam on the pipe, then place it on the outside of the bend. This must be done without fail otherwise the metal will disperse.
• It is necessary to determine the calculation of the radius of the future bend and clear the place of this bend. To do this, you need to use a grinder and make several cuts along the length of the marks. After carrying out this work, you can easily bend the pipe.
• The resulting gaps should be welded, then they should be cleaned. This work must be done slowly, and with special care. Thanks to this, you will not spoil the product, and the resulting result will please you.

Bending a pipe with a spring and a blowtorch

In this article we are talking about how to bend a profile pipe. Here we give those methods that can be used if there is no special device designed for this purpose. So, in order to bend a profile pipe in the following way, you need a steel wire 2 mm thick. It needs to be shaped like a spring in order to pass deep into the pipe. It should be said that such a spring should not dangle inside the profile pipe.

In order to bend the pipe, you can buy a ready-made spring, which will be designed for bending pipes. Then you will need to place it in the pipe, and mark the place of the bend. Next, we heat the product with a blowtorch. After the procedure, you can easily bend the pipe with a grinder. If the result does not please you, then you can fix it by redoing your work again, but with more accuracy.

Pipe bending with sand and a gas burner

If there is no pipe bender at home, and the profile pipe needs to be bent urgently, then use improvised means. In this part of the article, it is worth talking about how to bend a profile pipe without a pipe bender using a gas burner and sand. It must be said that this method will give the pipe the desired bend without the appearance of cracks and deformations on it.

1. To carry out this work, you will need sand (preferably quartz), and a gas burner, a drill and wooden plugs in the amount of 2 pieces. Next, perform the following steps in the prescribed order:
2. If you did not have quartz sand, it is quite possible to use the usual one, having previously carried out the procedure for cleaning it. Sand should be sifted and dried by heating it with a burner or fire. Heating must be done after the complete cessation of its smoking. Ready sand should be cooled and poured into a clean bowl.
3. One end of the pipe must be closed with a wooden plug. Next, we pour sand into the pipe, and we also clog its second edge with a second plug. Remember that such a filler will help to avoid various deformations and the appearance of cracks. If the pipe is empty, then it will deteriorate.
4. It is necessary to make a small hole in one of the plugs so that air can escape from it during the heating process.
5. Now you should make a mark of the place where the pipe will bend and heat it with a burner.
6. Next, we give the product the shape we need.

When carrying out this work, it is necessary to ensure that the metal does not overheat. This can lead to the appearance of scale, and this material will lose its original quality. When the pipe reaches its desired shape, the wooden plugs should be removed from the holes, and the sand should be poured out. For easier removal of plugs, you need to slightly heat the ends of the pipe.

Additional pipe bending methods

There are a large number of methods for bending profile pipes without a pipe bender. consisting of special materials that you can apply. Let's list them below for our readers.

So, in order to bend a pipe made of copper (or brass), you need to use water and exposure to low temperatures.

• One end of the pipe should be plugged.
• Then you should fill the product with water and close the other end of the pipe.
• You can fill it with either rosin or lead.
• Now it is worth placing the pipe in a cold place or in frost in order for ice to form.
• After that, the pipe will acquire the necessary shape.

In order to bend on a pipe consisting of metal-plastic, you need to take ordinary table salt.

• Before starting work, salt should be heated in a pan. This procedure must be carried out until the salt crystals begin to explode.
• Then we pour salt into the pipe. As soon as it gets inside, our product will take the desired shape and will easily bend.

Finally

Now you have learned how to bend a profile pipe with your own hands. In general, remember that various methods of bending pipes can make this work possible at home, without the use of expensive equipment and without the services of those people who do it professionally. We hope that our tips will help you bend the profile pipe using handy tools. So keep an eye on the process of your work and try to do it carefully and without haste. And the result will definitely please you.

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The need to bend profile pipes in everyday life is not often encountered. This task is most often faced by owners of summer cottages or private houses - people who are used to doing everything with their own hands.

Regardless of the shape of the pipe profile, the essence of the bending process is to give the product a partial or complete bend. This can be achieved only by applying a certain external influence - exclusively pressure or a combination of heating and pressure.

From the point of view of physics, in the process of bending, two oppositely directed forces simultaneously act on the profile pipe:

• Stretching force. Appears from the outside of the bend.
• Compression force. Directed to the inner part of the bent section.

The opposite direction of these forces is precisely responsible for some of the difficulties that often arise in the process of pipe bending:

• Different sections of the pipe in the bending zone may change shape unequally, which will inevitably lead to misalignment.
• The pipe wall on the outside of the bend may lose strength or even burst under strong tension.
• On the inside of the bend, on the contrary, folds often form during compression.

To avoid these troubles, and not to get a crumpled metal surface instead of an evenly curved pipe, you should definitely take into account the type of material and numerous geometric parameters of the product: wall thickness, cross-sectional diameter, bending radius. Knowing these characteristics will allow you to choose the best way to bend.

Note! Experts say that it is better not to bend profile pipes with a wall thickness of less than 2 mm. The strength at the bend points will be quite low, even with perfect adherence to technology. For such pipes, it is better to prefer welded joints.

The principle of using a pipe bender

It is far from always possible to bend a profile pipe (especially for large-diameter products) with your own hands. For these purposes, there are special devices - pipe benders. A standard pipe bender is equipped with a driving wheel, which, moving along one of the edges, gently bends the pipe section in the required direction.

Demanded in many areas of life.

They are used to make designs of various products in industry, construction and everyday life. Often for these purposes it is necessary to give such pipes a bent shape with the help of a certain deformation. Bending profile pipes can be carried out using special machines called pipe benders.

Without a pipe bender, it is difficult to give the product the desired shape. They can be purchased ready-made, produced under industrial conditions, or you can do it yourself if the need for such a machine arises periodically for home needs. For this, it is important to know how you can make your own device for bending profile products.

Do-it-yourself two options for bending profile pipes are used: cold and hot.

Both of them aim to maintain the integrity of the profile shape when the product is bent. To do this, in contrast to the external compressive force during the bending procedure, the inner space of the profile is filled with a certain substance that prevents squeezing.

With a cold method, such a substance is frozen water, and with a hot method, river sand.

Features of the cold method

Bending the workpiece using water is usually used in winter during severe frosts. To do this, the profile pipe is hermetically sealed on one side with a cork plug, and on the other side is filled with water.

The product is left in the cold in a vertical position with the sealed side down until the water completely freezes. After that, the process of bending the product to the desired radius is carried out.

hot bending method

The method is based on heating the bend area of ​​the profile product. It can be applied at any time of the year. The pipe is also sealed at one end by closing with a cork or any improvised means.

Then river sand is poured inside on the other side and the end is closed with a plug. The length of the plug must exceed the diameter of the pipe by about 2 times so that it can withstand the weight of the sand placed in the pipe.

The place of the fold is marked with chalk or a marker and it is heated. To discharge the gases formed during heating, it is desirable to drill small holes at the ends of the product.

When the section is heated to the desired temperature, the pipe is bent on a machine that corresponds to the parameters of the product.

Important! When bending the pipe, it is not necessary to allow sparking of the metal.

The scheme of the hot method for bending a profile pipe is shown in the figure:

Design features of machines for bending various profile pipes

Despite the simplicity of bending profile products, their characteristics must be taken into account before proceeding with bending.

The design of the bending device should be chosen taking into account the dimensions and properties of the material of the profiles. This is due to the fact that products of different diameters and wall thicknesses, as well as those made of various metal alloys, have different critical minimum bending diameters.

Its values ​​are indicated in special tables, which take into account all pipe parameters. When the profile is bent below the critical value of the radius, the strength properties of the metal at the bend are significantly reduced.

Specifications table:

A do-it-yourself machine for bending a profile pipe can have a different device. Its complexity depends on the parameters of the pipe and its characteristics.

For products with a cross section of up to 2-2.5 cm, you can use the simplest device options using a concrete slab or a prepared template for the planned bending arc.

For cross sections of larger profiles, the design of the machine is more complex, it uses the method of bending when squeezing the pipe while passing through the rolls in the likeness of a rolling mill.

Let us consider in more detail how to manufacture such devices.

Simplified types of pipe bender

1. With concrete slab

To create a structure, you will need a concrete slab, a diamond or concrete drill bit and metal pins.

The manufacture of the device is carried out as follows:

• a schematic grid with cells of 4×4 cm or 5×5 cm is applied to the surface of the concrete slab;
• at the intersection of the grid lines, recesses are drilled for metal pins;
• the pins inserted into the cells are carefully fixed with concrete pouring to prevent them from falling out under the action of the load from the pipe.

A diagram of such a device is shown in the figure:

The profile bending process is carried out as follows:

1. The pipe is inserted between two adjacent pins, and with the help of force it is bent in the right direction. The bending radius can be changed by moving along the elements of the pins located diagonally.
2. The bending force must be applied gradually to prevent unnecessary deformation of the profile. To facilitate the work, the profile can be subjected to a slight heat.
3. Immediately after deformation, it is not recommended to remove the pipe from the device in order to fix the resulting bend. For reliability, the ends of the product are temporarily welded to an auxiliary steel bar.

2. Using a template

The simplest device for profile products, in demand for home use, is the method of bending according to a pre-prepared template. It is possible to bend not only products made of aluminum alloys, but also steel pipes of small sizes.

The template is made of wooden boards, having a thickness slightly greater than the diameter (section size) of the product being bent. For the convenience of work, the template boards are sawn at an angle towards the plane of the table. The template itself is fixed on the table with screws.

In addition to it, an emphasis is fixed on the working plane of the table at a small distance from the template to hold the pipe.

Roller machine design

The principle of operation of such a machine is based on rolling a profile pipe through moving rolls, in which it acquires the desired bend under pressure. The movement takes place with the help of two horizontal rollers mounted on the base of the channel.

A homemade machine can be made with the following parts available:

• three rollers having an axis of rotation for bending;
• profile channel for the manufacture of the base frame of the machine;
• drive transmission chain;
• driving mechanism.

The order of manufacture of the machine should be as follows:

1. First you need to make a frame frame from a metal channel. The elements of the channel for the frame can be connected by welding, but for reliability, it is better to fix the structure with bolts.
2. A U-shaped structure is installed vertically in the center of the horizontal frame, on top of which a shaft with a coupling is attached. A pin is inserted in the center of the coupling, onto which a handle is welded, and a roller is installed on the side.
3. Two cylindrical rolls with rotating rollers are mounted on a horizontal frame of the machine base at the same distance from the center.
4. A chain is attached to the rollers to set the mechanism in motion by means of a manual drive.

Rolls are fastened with bolts. To do this, slots are drilled into the channel to allow the rolls to move to change the bending radius setting.

Work on such a homemade machine is carried out as follows:

• the profile pipe is inserted onto the horizontal feed rolls;
• by turning the handle, the clamp presses the pipe with the third roll. As a result, the profile is deformed when passing through this zone.
• the initial deforming pressure will change the configuration of the pipe slightly, so the process of pulling through the rolls must be repeated until the desired bend is obtained.

The profile bending radius depends on the distance between the lower cylinders, which can be changed using rollers by moving them and fixing them with a stopper.