How to bend a profile pipe

Description of methods for bending a profile pipe at home - Machine

Such structures are made from bent pipes, since they transmit a lot of light and are highly stable and durable when compared with other devices. It may seem that bending metal is very difficult, but if you understand this issue , then it is quite possible to effectively perform this procedure yourself and without the use of special tools.

Difficulty in bending profiles

The essence of the process of bending rolled metal is to give the profile a partial or full bend. This operation is usually performed in two ways : by applying pressure to the pipe or by heating a certain area in the area where the bend needs to be made.

As a metal pipe bends, two forces act on the surface of the metal:

The compressive force that falls on the inside of the bend.
The tensile force to which the outer part is subjected.

It is precisely the influence of such multidirectional forces that causes various difficulties that are typical in the process of bending any metal pipe.

Common Problems

The wall, which is located on the outside of the bend, will be subject to strong stretching, and therefore may not withstand any loads and simply burst.
The inner wall is also subject to compression, so it is covered with folds that resemble corrugation in shape .
Many people who try to bend a pipe on their own for the first time, instead of giving it the required shape, simply crush the product and ruin it.
To avoid such problems, it is necessary to take into account not only the characteristics of the material, but also geometric parameters, such as:

Wall thickness;
section dimensions;
the radius to which the bend must be made.

If you have information about all of the above, you can choose the appropriate pipe bending technology. As a result, the material will not wrinkle or get a corrugated surface.

Profile accounting

Profile pipes include products that have different cross-sectional shapes:

square;
round;
flat-oval;
oval.

A large number of profiles are sold in stores. There are different geometric parameters, the main ones of which are cross-sectional area and wall thickness. It is also worth looking at the plastic capabilities of the material. This indicator will show the minimum acceptable radius of curvature and will help determine the radius to which the pipe can be bent so that it does not deteriorate.

To determine the minimum bending radius parameter, you need to know the profile height. If you are going to bend a profile pipe that has a rectangular or square cross-section, then you should follow some recommendations.

If there is a profile no more than 20 mm, then it must be bent in those areas whose length exceeds a value equal to 2.5 xh (h is the height of the profile).

If the product profile exceeds 20 mm, then it can be bent in areas whose length is 3.5 xh or more.

These recommendations will be useful to those people who are going to bend a metal profile with their own hands to make a rack, canopy or other similar structures.

But it should be borne in mind that for high-quality bending it is also necessary to take into account the wall thickness. A product whose thickness is less than 2 mm is completely unsuitable for bending, and therefore it is necessary to choose a thicker structure.

If the wall thickness is less than 2 mm, then it is better not to bend the pipe, but to use welding to connect the parts.

If you need to bend a pipe at home that is made of carbon or low-alloy steel, you need to take into account a number of nuances. Such metals, after bending, can spring back and return to their original position, and therefore such structures must be re-checked using a template.

The amount of springback is characterized by such a parameter as the moment of resistance - Wp. This parameter is indicated in the construction documentation. And the lower it is, the less likely it is that the profile will return to its original position during bending.

Before bending, only pipes with a cross-sectional diameter greater than 10 cm should be heated.

If you need to bend square or rectangular structures, then you should only rely on your own experience and the advice of craftsmen who have already been involved in such an operation.

If the profile height is no more than 10 mm, then it is not necessary to bend it using heat. If the profile is larger than 40 mm , then heating is required.

If the pipe is small in size, it can be bent in a cold state using hand tools.

To obtain a workpiece with a small bending radius, you can use a stationary plate with stops or a vice, as well as a roller device.

If a large radius of curvature is required, then you need to use fixed mandrels or plane-parallel plates on which the part can be fixed.

When hot, the metal must be bent only if the profile height exceeds 40 mm. Heating is carried out using a blowtorch or gas burner flame. The pipe should take on a cherry-red hue. The length of the red section should be approximately 6 pipe diameters.

Of course, the easiest way to bend is to use a pipe bender; with it you can very easily cope with the task. If there is no such device, then it is necessary to conduct preliminary tests on an unnecessary piece of metal.

Then it will be possible to decide whether the pipe should be heated or whether this is not necessary. One end of the pipe must be clamped in a vice, and a tube with a large internal cross-section must be attached to the other.

If you can bend metal with such a lever , then the process can be carried out without heating.

Preheat

In order to bend a pipe yourself using the hot method, you must first fill it with sand. This way the bending will be uniform and of high quality. The metal will be very hot, and therefore all work must be carried out with special gloves.

Bending is carried out in the following sequence:

Both ends of the pipe are plugged with plugs. The length of the plugs should be 10 times the width of their base.
After the fitting of the plugs has been successful, it is necessary to make 4 longitudinal grooves on one of them, through which gas vapors that accumulate inside when heated will escape.
The area that will heat up must first be annealed.
Medium grain sand should be poured inside. If you don’t have good cleaned sand, you can take any from the playground, but first you need to sift it through a good sieve to remove all the small pebbles.
Preparatory sand must first be calcined at a temperature of 150 degrees Celsius.
Before filling the sand, one end of the pipe must be plugged, and the plug must be inserted into the second end only when all the sand is completely inside. To fill the pipe completely with it, you need to tap on the walls of the product. To do this, it is better to take a wooden or rubber mallet.
Now you can close the second plug.
The area that will be heated must be marked with chalk.
The pipe is secured in a vise with a template or in a special clamp. Do not clamp the weld if there is one, as it may burst.
The area that was marked with chalk is heated red-hot using a burner. Then they carefully begin to bend the pipe in one step, applying enough force.
When the metal cools, the product must be compared with the template. If everything is fine, then plugs and sand can be removed from the pipe.

This method can be easily applied at home, and should be used if there is a need to form a single angular bend. It is better to avoid repeated heating of the material , since strength will be lost, and this will be detrimental to the arched structure.

Bending without heating

If the pipe is small, then instead of sand you can fill it with a steel spring, which will ensure uniform deformation. You need to choose a spring so that it fits inside freely, but sits there tightly enough. To avoid problems with removing the spring after the operation, it is necessary to attach a wire to the extreme link.

The bend is obtained using simple devices such as a vice, bending plate or mandrel.

It is much easier to use a manual pipe bender, which has a round profile. Working rollers are attached to this device, the shape of the recess in which corresponds to the profile of the pipe .

A profile bending machine, which you can purchase or make yourself, is very effective in bending.

Bending devices

Cold bending can be performed using the following devices:

If the pipe is soft and steel with a profile height of no more than 10 mm, then you will need a flat plate with holes where the stops will be inserted. Using these pins, bending will be carried out according to the required parameters. This method has disadvantages: the bending is not precise enough, and when applied, a large amount of physical force must be applied.
If the profile is 25 mm high or more, then roller devices must be used. The pipe must be firmly fixed in a vice, and the force must be applied using a special roller. Such a device will allow you to get a better bend, but it will also require a lot of effort.

Bending plate

The role of the plate is played by a panel that can be cut from thick metal. Such a panel is welded to a stand that is installed on a special pedestal. 2 holes are drilled into the panel to install bolts that will serve as supports. A nozzle is attached to one bolt, with which the bending radius will be adjusted. To ensure alignment , you need to prepare a metal plate and secure it with bolts.

Bending a profile pipe at home is, of course, not an easy task, but it is quite doable. You just need to have some plumbing skills and tools.

Source: https://regionvtormet.ru/beton/opisanie-sposobov-sgibaniya-profilnoj-truby-v-domashnih-usloviyah.html

How to bend a profile pipe without a pipe bender at home

21.03.2018

The task of how to bend a profile pipe very often faces home craftsmen. Structures made from profile pipes are multifunctional and convenient. They are used to create greenhouses and canopies, fences and supports for plants, shelving and more.

The result is a very durable, stable and relatively inexpensive structure. At first glance, the task of bending a profile pipe without a pipe bender seems impossible to solve.

However, if you know some of the subtleties of the upcoming task, giving a profile pipe an arched shape yourself, at home, is not so difficult.

The task: bending a profile pipe without a pipe bender is solvable!

The essence of the work and the main mistakes

Before bending a profile pipe at home, you need to clearly understand what lies behind bending. Regardless of the shape of the profile pipe, we have to give it a bend of a given radius. The result is achieved either by purely mechanical action, or by using additional heating of the profile. In this case, two different forces act on the pipe at one moment:

From the side of the profile into which it is folded, the compression force works.
A tensile force acts on the outer surface of the workpiece.

It is precisely because of the multidirectionality of the acting forces that bending a profile pipe at home is not so easy. A fragment of the workpiece may lose alignment, resulting in a multi-level arrangement of pipe segments. The outer surface at the bend may burst under stress. From the inside, a profile pipe can be folded by compression, making the surface look like corrugation. In addition to the unsightly appearance, this outcome makes the profile fragile.

Possible pipe deformation

If you do not follow the technological nuances, you will not be able to give a profile pipe a curved shape at home without defects. You can spoil a bunch of blanks without achieving the desired result.

So it is imperative to take into account the physical and chemical parameters of the material from which the pipe is made, the cross-sectional dimensions of the workpiece and the thickness of its walls, the radius of the intended bend; ideally, it is necessary to calculate the load on the profile pipe.

Knowing all these parameters makes it possible to bend a profile pipe without damaging the workpiece.

Features of different types of profiles

Profile pipes are produced with a wide variety of cross-sections: in the form of a circle, square, rectangle, oval. At home, craftsmen prefer to use square and rectangular rolled metal. The explanation for this choice is simple: the external coating is attached to pipes of this type easier and more reliably.

At home, craftsmen prefer square and rectangular rolled metal

To determine the permissible bending radius of a square or rectangular profile, you need to know its height and adhere to these rules.

With a profile height less than or equal to 20 mm, a pipe without defects can be bent on sections that are longer than 2.5 times h, where the letter h denotes the height of the pipe section.
Rolled metal with a profile of greater height is allowed to be bent in areas calculated according to the formula 3.5 * h. If the length is shorter, the workpiece will most likely be damaged.

Before bending a profile pipe at home, also pay attention to the thickness of its walls. If they are thinner than 2 mm, it is better to refuse bending: a high-quality bend will not work. When using such rolled metal to create pipe structures, it is better to connect them by welding.

Bending a profile pipe made of low-alloy or carbon steel has its own characteristics. Such blanks spring back after bending, returning to their original form. So the master will need to re-fit according to the template. In some cases, secondary bending can be avoided by initially setting the bend radius larger than required. Then springing will lead the pipe to the planned result at the end of the process.

The degree of springback is characterized by the plastic moment of resistance, denoted Wp. Its parameters must be included in the documentation for rolled metal products. The lower Wp, the less the workpiece will spring when bending.

Metal bending methods

It is possible to bend a profile pipe either cold or by heating. Heating is carried out with a gas burner; at the same time, the plasticity of the material increases noticeably, and achieving bending will take less effort. However, workpieces with a small cross-section have sufficient plasticity even without heating, so that you can do without a burner.

Clear rules regarding the use of heating are developed exclusively for pipes with a cross-section in the form of a circle. It is considered mandatory when bending workpieces whose diameter is more than 10 cm.

When working with square or rectangular profile pipes, you have to rely either on your own experience or on the recommendations of other craftsmen. As a first approximation, you can focus on the following tips:

If the profile height is less than 10 mm, heating can definitely be avoided.
If the cross-sectional height of the pipe is more than 40 mm, it is necessary to heat it before bending.

With intermediate values of this indicator, the bending method is left to the discretion of the master. To decide on a method for bending a profile without a pipe bender, you can carry out a simple test. One end of the workpiece is clamped with a vice. A piece of pipe having a larger internal cross-section diameter is put on the free end. Pressure is applied to the resulting lever with your hands. If the rolled metal can be bent, then further bending according to the desired template can be done using a cold method.

Cold bending

Without heating

A small profile pipe without a pipe bender is actually bent by hand, using simple devices.

To bend the workpiece under a not very significant radius, securely fixed plates equipped with stops, roller devices, and a vice are used.
If it is necessary to obtain a bend of a significant radius, devices in the form of fixed mandrels or plane-parallel plates with a mounting clamp will be required.

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To obtain a smooth bend, pipes with a profile height greater than 10 mm are recommended to be filled with filler. Medium-grained sand or rosin is usually used as it. An alternative method to bend a workpiece without heating and a pipe bender is to use a densely wound spring instead of a filler.

This method is especially good in cases where the walls of the rolled metal are too thin. The spring is selected in such a way that it fits freely into the profile pipe, but at the same time fills it quite tightly. To make it easier to remove the “filler” after bending is completed, a wire is securely attached to the end of the spring.

If you have some metalworking skills, you can make a spring of a given size yourself, from steel wire 2 mm thick.

Hot bending method

If you decide to bend the pipe using heating, you must fill it with filler. Since you will have to deal with high temperatures, the mandatory set of “equipment” includes protective mittens made of tarpaulin.

The order of work is followed as follows.

Two plugs are made using wooden blocks. The base of the “plug” has an area twice the cross-section of the pipe, and its length is chosen ten times greater than the calculated width.
One of the plugs, already adjusted to the cross-section of the element being bent, is equipped with 4 longitudinal grooves. They are needed to remove vapors that will be released during heating of the filler and accumulate inside the pipe. If the gas is not given the opportunity to escape, the plug will be knocked out, and the workpiece will be damaged when bent.
The area of the workpiece to be bent is annealed before processing.
The simplest, most accessible and cheapest way is to use medium-fraction sand as a filler. Ideally, cleaned construction material, but you can even take the most common one, used in children's sandboxes. It will just have to be subjected to additional processing. First, the sand is sifted to remove foreign inclusions. At the first stage, a sieve with cells no larger than 2.5 mm is used, at the last - with a cell of 0.7 mm. This step will ensure the removal of dust impurities. The sand is calcined throughout its entire volume (processing temperature - 150 Celsius). Calcination is a mandatory step: without it, the sand remains too wet, and the steam pressure inside the bent fragment during operation of the gas burner can be so great that the profile pipe will simply burst.
One of the ends of the profile pipe to be bent is clogged with a plug without gas outlet channels.
A funnel is installed into the second hole that remains open, through which sand is poured. Filling must be done in portions so that the bulk substance fills the cavity as evenly as possible and as densely as possible. After introducing the next portion, the pipe should be tapped with a mallet - rubber or wooden. Insufficiently dense packing leads to wrinkling of the bottom surface of the pipe or rupture of the top.
When the workpiece is filled to the top with filler, the open hole is closed with a second plug.
The bend location is marked with chalk.
The bent element is fixed in a vice with a template. You can also use a pipe clamp. If there is a weld on the pipe, the workpiece is attached so that it is on the side (not on top or bottom). This rule must be observed: it is strictly not recommended to expose welded seams to tension or compression.
A piece of pipe marked with chalk is heated red-hot with a gas burner.
Having achieved the desired degree of heating, the pipe is bent with a smooth movement, without sharpness, in maximum accordance with the template. This must be done in one movement; the efforts during bending with the arms are applied strictly in a certain plane, either horizontal or vertical. Otherwise, alignment will be disrupted. For bending, a piece of pipe with a larger cross-section is placed on the free end of the workpiece. It should fit freely onto the element being processed, but should “sit” tightly on it.
When the pipe has cooled, the bend is compared with the template. If it corresponds to the idea, you can remove the plugs and get rid of the sand. If serious deviations from the pattern are observed, the procedure must be repeated. It is still advisable to complete the task on the first, or maximum on the second try. Otherwise, the workpiece will be hopelessly damaged.

During the pipe bending process, you need to monitor the degree of its heating. Excessive overheating is unacceptable; If this happens, you need to cool the workpiece a little naturally.

When bending is completed, the plugs are knocked out. If they fit too tightly, the plugs are burned out with a gas torch.

The hot method of bending a profile pipe is quite suitable for implementation at home. However, it is better to use it in cases where the element needs to be given a single bend. Repeated heating of the pipe entails a loss of strength in the metal.

Bending a pipe using a grinder and a welding machine

Cutting method

You can give the profile pipe the necessary curved shape with your own hands, and with the participation of an angle grinder accompanied by a welding machine. To do this, cuts are made across the element in the intended area, not reaching the end. Then the pipe is bent to the required radius, and the cut points are welded.

The final product will retain a fairly aesthetic appearance (to achieve this, it will be enough to carefully grind the welds) without loss of strength characteristics. The only limitation is that the outer cladding should not have too much weight. For the equipment of the same greenhouses or canopies with awning covering, this method of obtaining a bend can be an ideal choice.

The advantage of the technique is that the profile can be bent to any degree of curvature, which other methods usually do not allow.

How to bend a profile with your hands

Finally, we note: bending the profile by hand, in the absence of a pipe bender, makes sense only if it is planned to bend a small number of elements.

When there are a lot of workpieces to be processed, it is better to spend a little money and buy the appropriate device: it will significantly reduce the time and effort of the craftsman.

In the same way, if you only need one element with a bend, it makes sense to think about buying it - it won’t cost you much, but it will save you a lot of hassle.

Watch a video on this topic:

How to bend a profile pipe without a pipe bender at home Link to main publication

Source: https://viascio.ru/materialy/kak-sognut-profilnuyu-trubu-v-domashnih-usloviyah

How to bend a profile pipe at home without a pipe bender yourself

Experienced summer residents and owners of their own homes have long appreciated the versatility and convenience of profile metal pipes. They are used in the construction of porticoes, extensions and gazebos, and are also used as struts for greenhouses and greenhouses. They are also often needed in the manufacture of decorative elements.

When using corrugated pipes in home construction, they are usually bent to give the required shape. There are several common methods by which you can perform this operation without purchasing specialized equipment such as a pipe bender.

Features of bending professional pipes

Regardless of the specific configuration of the profile pipes, the bending process is a mechanical force that gives the workpiece partial or full radial or angular bending.

According to the basics of mechanics, during work, a set of forces in different directions acts on a profile workpiece:

compression, which has a deforming effect on the surface of the inner part of the pipe;
tension affecting the outside of the pipe at the bend point.

It is impossible to bend a profile pipe without taking into account the mechanical characteristics of the shape and the material from which it is made. Otherwise, some parts of the workpiece will be completely damaged and unsuitable for use in construction. Another risk associated with incorrectly performing the operation is the risk of the workpiece breaking on the outer (upper) surface during bending. Due to a violation of the technology, the pipe will have to be thrown into the trash or cut into smaller parts.

In order to bend a corrugated pipe yourself, in a home workshop or garage, you don’t need to know all the engineering subtleties of strength-of-material materials.

It is only necessary to take into account the universal rule:

a thin-section pipe (about 20 mm) bends without deformation over a section 2.5 times longer than the height of the profile walls;
with a section of 30 mm and above, it bends over a length of section 3 times the height of the section.

Thus, the radius of the inner surface of the bend (R) is determined as: wall height * 2.5 (or 3 depending on the height of the section).

Finally, another important factor is the elasticity of the metal. Because of it, the profile after bending, trying to return to its original shape, bends back, deviating from the given curvature. Therefore, when bending a profile pipe, craftsmen recommend making the bend a little deeper.

Safety precautions

To perform bending and any other operations with metal products, it is better to prepare a separate room.

A garage or workshop is suitable, since in addition to the structures themselves, for work you will have to use, for example, a blowtorch or an argon gas torch, impact or cutting tools.

The work site must be ventilated and free of clutter. Otherwise, sparks during cutting or careless handling of the heat source when heating the metal can lead to fire and smoke.

The experts also recommend taking care of special clothing. An apron and mask will protect you from small fragments and dust, and mittens will protect you from temperature influences and possible cuts. If you have to use an angle grinder, special glasses will be a must.

Bending methods

In order to effectively bend the profile, they resort to the help of specialized, usually expensive, professional tools - the so-called pipe benders. If the homeowner or summer resident is not ready to spend money on the purchase, then you can bend the profile to the desired curvature yourself in a home workshop.

Technologically, methods of radial curvature of profile pipes are divided into “hot” and “cold”. In the first case, bending is carried out on a preheated surface area; in the second, there is no need to heat the pipe before mechanical impact.

Hot method

Heating the metal before bending it is a procedure that makes the structure more viscous, which makes bending the profile much easier.

The workpiece is clamped in a vice and heated using a torch or blowtorch at the intended bend point.

After this, the heated profile (the color of the material should be reddish-white or reddish-yellow) is removed and “screwed” onto a specially prepared blank, made according to the shape with the required angle and radius of curvature.

Important. Using this method, if the bending is insufficient, the metal can be heated again, but this should not be done repeatedly - each time the profile pipe cools down (the color becomes light cherry), its strength characteristics decrease. At some point this may lead to a break or rupture.

We use fillers

Another “universal” technique for changing the curvature of a hollow profile metal structure is the use of a filler that will protect the corrugated pipe from crushing. Depending on the height of the pipe walls, when using fillers (sand or water), “hot” or “cold” bending is used, respectively.

Bending a hot sand-filled surface

In order to reduce the risk of deformation of the workpiece during “hot” bending, sand is first poured into it, which is sifted through a fine sieve (up to 2.5 mm) to break up the “lumps” and remove invasive solid particles.

Using a wooden plug or plug, one end of the workpiece is closed, after which, through the second (open) end, the workpiece is tightly compacted with sand. To make sure that it is evenly distributed, knock on the pipe profile with a rubber or wooden hammer.

As soon as a dull sound is clearly heard along the entire length of the workpiece, it means you can hammer the “upper” end with a second plug. A small longitudinal hole is made in the plug so that during the heating process the gas that accumulates from heating can be etched out there.

After this, the profile pipe is fixed in a vice, heated at the marked rounding point, and with the help of physical force it can be bent to the desired shape. The bend is performed in one grip, smoothly and accurately. Then the plug is removed or burned out, and the sand is poured out of the pipe.

Reference. If it is inconvenient to clamp the profile in a vice due to its length and wall thickness, bending using this method can be done outdoors. To do this, the lower end is not clogged with a plug, but buried in the ground.

Cold bending with water filling

On winter days, when the air temperature drops below minus 5-10 degrees, water filler can be used instead of sand filler to bend the corrugated pipe. The method requires minimal costs, but applies only to thin profiles made of duralumin or brass. There is no need to heat the metal.

The bottom line is that the sealed workpiece is filled with water, and then taken out into the cold and kept there until the liquid completely hardens.

After this, the already frozen part is bent along the profile of the blank template. The profile bent to the required radius returns to the heat. After complete thawing, the water inside is drained.

Applying templates

In a home workshop, “cold” bending of profile pipes is carried out using special templates - mandrels or bending plates.

Mandrels are made from materials available at hand - taking into account the thickness of the profile section and the volume of work.

If the cross-sectional height of the pipes is no more than 3 mm, then in order to bend them to different radii, it is necessary to make one or more template mandrels. The mandrel is fixed on the workbench, and the corrugated pipe is laid and fixed along the rim of the mandrel with loops or hooks, bending the workpiece starting from the middle and gradually moving to the ends.

Another template device is a horizontal bending plate - a surface made of strong wood or metal in which holes are drilled at a certain distance into which strong pins or bolts are screwed or inserted. They will be stops around which the corrugated pipe is bent at certain angles and according to a shape determined by the master. It can be modular, which allows you to attach it to a workbench and, after work, disassemble and reassemble it for reuse.

Important. A significant “disadvantage” of these devices is the difficulty of performing precise curvature of the workpiece, since this will require serious muscular effort.

Rolls

Rolls or roller shafts allow you to make a pipe-bending lever unit in your own workshop, which works in a similar way to its factory counterpart.

The distorting effect on the workpiece occurs under the action of a lever that bends the pipe around the surface of the roll circumference.

Such a device is made using three rollers arranged in a triangle. With the help of a lever, the fastening axis of one of the vertices can be shifted inside the triangle, which ensures the curvature of the workpiece located on the other two rolls.

The unit is capable of bending profile pipes of various thicknesses and at various angles, which makes it “universal” in the manufacture of arch-type structural elements. The lever mechanism, at the same time, significantly reduces the force required to bend the parts.

Springs

A useful device for manual bending of a profile is a spring.

It is made of dense wire (about 2 mm) with a diameter such that it fits freely into the inner surface of the profile.

The spring is threaded into the profile, bending it to the required shape and radius of curvature. To make work easier, the bending area is heated.

Important. To prevent the spring from getting stuck in the bent pipe after the operation is completed, it is best to attach a wire or ring to the end of the spring, by which it can be pulled out.

Bulgarian

The original way to bend a professional pipe is to use a grinder.

To make an angular bend, use a grinder to make 2-5 transverse cuts at the intended point on the inner surface of the workpiece, without touching the outer wall.

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Their number directly depends on the size of the angle - the larger it is relative to the straight line, the more notches are applied.

After the notches are made, the profile can be carefully and effortlessly bent, and the notch areas are welded using a soldering iron or welding.

If you then, when the pipe has cooled, grind and sand the welding points, the profile will correspond to the shape required by the master.

Bending with a lever

Finally, another “cold” method of bending a corrugated pipe is a lever. It is a handle made of metal or strong wood, onto which a “nozzle” with a hole is nailed or welded from below.

During operation, the profile blank lying on the floor is threaded into the nozzle up to the bending area. After this, the master presses the handle “on himself” and with the created force bends the profile. This method is not distinguished by the accuracy and precision of rounding the structure, but it can be used in any conditions.

To summarize, we can say that there are many opportunities to bend a profile pipe in a regular garage or workshop without expensive pipe bending equipment.

It won’t be difficult to build a specialized tool or make the necessary mold yourself. And it will cost much less. If a novice craftsman does not yet have confidence in his abilities, he can contact construction and repair companies to hire a worker or rent the necessary equipment.

Source: https://2lzz.ru/sovety/kak-sognut-profilnuyu-trubu-bez-trubogiba

How to bend a profile pipe at home without a pipe bender?

Almost all summer residents and owners of private houses have to face the question of how to bend a profile pipe at home without a pipe bender.

Arches from profile pipes are used in the construction of greenhouses, gazebos, canopies and arched canopies. Purchasing special bending devices or making them yourself is not economically profitable.

They are needed for mass production, not individual production. Let's look at what methods exist for bending profile pipes to the required radius.

What is the problem with profile bending?

The essence of this process is that one side of the pipe is stretched, and the inner part is compressed. Pressure is applied to the workpiece, which may be accompanied by heat, to make the metal more pliable.

Bending a profile pipe along a radius with your own hands is associated with the following difficulties:

displacement of the longitudinal axes and planes of the part, which leads to misalignment;
rupture and appearance of cracks on the outer part of the workpiece under the influence of tensile force;
uneven compression of the inner part, leading to a corrugation effect;
change in the diameter or shape of the workpiece.

To know how to properly shape steel pipes into an arch, you need to take a number of factors into account.

Influence of material on the choice of bending method

Profile pipes are made in accordance with the requirements of GOST 54157-2010 and have certain properties.

It is necessary to bend profile pipes taking into account the following parameters:

The minimum bending radius of the facing material that is planned to be laid on the arches. For cellular polycarbonate, these indicators depend on the thickness and structure.
Profile size and wall thickness. Products with a wall height of up to 10 mm can be bent using muscle force. Profiles from 20×40 mm and larger must be bent in a complex manner using pressure and heat or on a machine.
Elasticity (plastic moment of resistance). It must be included in preliminary calculations, giving the workpiece a smaller bending radius.

Based on the analysis of this data, a choice is made on how to perform the task.

Bending methods and bending devices

Using available materials and household tools, you can make a bending device at no additional cost.

As for professional devices, their cost can be several times higher than the price of the material for making arches.

Let's look at ways in which you can make bent rectangular arches of an ideal shape.

Cold

Without heating, cold steel is bent if the master’s muscular strength is sufficient for this procedure. As a rule, these are square pipes with a cross-section of 10×10 mm and rectangular pipes with a cross-section of 10×20 mm.

If the walls of the workpieces are thick, then filling the internal cavity with resistance is not carried out. Let's consider the main options for creating arches from metal blanks.

Lever with nozzle

First, a pattern is made with a certain semicircle length corresponding to the specified parameters. It is made from chipboard, plywood, drywall or boards.

After this you need:

Securely secure the vise to a heavy, stable table. A piece of pipe with a larger size than the workpiece is firmly fixed in a vice;
perform bending in several stages by inserting the profile into the hole of the section clamped in a vice and applying force to it.

A lever of sufficient length is attached to the bent fragment to create the necessary pressure to deform the metal. During the work, the curvature is controlled by a pattern.

By mandrel

The mandrel is made on a solid base, which is a concrete or asphalt platform or a large workbench. In essence, this is a special template along the contours of which the profile pipe will bend.

Taking into account the degree of elasticity of the metal, the master needs to give the mandrel a smaller radius.

The procedure is carried out in the following sequence:

the part is securely fixed to the base;
the end of the workpiece is screwed to one of its edges with wire or clamps;
the profile is bent until it is given the desired shape.

The template can be replaced with reinforcement driven into the ground. As the pipe deforms, it is successively welded to the pins. After finishing the work, the arch is cut off from the stoppers.

Using internal countermeasures (sand, water)

This method is used when the profile parameters are less than: height 10 mm, width 20 mm, wall thickness 1 mm. Pipes filled with a dense substance retain their shape better, even under strong pressure on a small area of the product.

The use of sand and water guarantees a high-quality result without defects. And this factor is important, given the cost of rolled steel.

The filler must fill the entire volume of the profile pipe cavity. It is much easier to achieve this with liquid. The sand is compacted by vibration and spilled with water. The holes on both sides are welded or tightly clogged with wooden plugs. If heating is used, it is important to leave one side unclogged to allow gases to escape.

Grinder cutting and welding (sector welding)

Cutting with a grinder and welding does not require significant effort. The master needs to be prepared for the fact that this event will take a lot of time. The advantage of this technology is that there is no chance of damage to the profile; its shape can be adjusted throughout the entire bending process.

The work is carried out in the following sequence:

A diagram is drawn up. It shows the distance between the cuts and their configuration.
Markings are applied to the profile. Using a grinder, triangular cuts are made along it. The cut fragments are removed.
The workpiece is bent. If the metal is elastic and unbends after compression, then the joints are immediately fixed by spot welding.
The cracks remaining after compression are welded or sealed. After the metal has cooled, the seams are sanded and painted over.
The edges on the arch are almost invisible. When laying polycarbonate, small differences are compensated for by a thick seal.

Hot

Preheating is carried out in cases where the profile pipe has a large cross-section or thin walls. That is, it is either impossible to bend it manually, or it is fraught with damage or breakage of the workpiece. Let us dwell on the techniques that are used for thermal bending of rolled steel.

Using a spring and a blowtorch

The spring is needed to prevent the profile walls from being pushed through during bending. In addition, the elastic insert will give the finished product a neat and even shape. It must be strong enough to absorb and withstand the pressure exerted on the profile.

One end of the section is rigidly fixed in the ground or in a vice. Before bending the fragment, it is heated until the metal turns red.

You can cool the bent area only with warm machine oil - water causes the iron to crack and become brittle.

Using a spring and a blowtorch saves the worker from exerting unnecessary effort.

Hot forming

It is possible to give the desired shape to the profile without preliminary internal filling. When heated, steel becomes so soft and flexible that it can be bent by hand, without the use of levers or complex devices.

For this purpose, a convex semicircular stop is made. It must be made of material resistant to high temperatures. A car wheel or fireclay brick coated with clay is best suited for this. The heated part is applied to the template. After this, it bends in one slow and precise movement. After a few minutes, you can continue the procedure.

Tips and tricks

Giving profile pipes an arch shape is a complex process that requires skills in handling household tools and metal.

When making arches, you should adhere to the following rules:

It is easier and more convenient to work with short workpieces. Before bending, it is advisable to cut the parts into segments 1.5-2 meters long. Subsequent welding will not weaken the strength of the finished arch.
Heating of the metal should be done slowly to prevent uneven heating and deformation. The resulting scale must be cleaned off immediately, as it causes corrosion.
Rolled steel cannot be exposed to temperatures above + 800 ºС. This impact leads to the destruction of the metal crystal lattice. The profile becomes soft or brittle.
All bending actions should be performed slowly, gradually increasing the load.

How much does it cost to bend a profile for a greenhouse?

The cost of services is determined by the status of the workshop, its geographical location and the equipment used.

The average price for bending profiled steel is (in rubles per linear meter):

10×10 — 80;
20×20 — 100;
25×25 — 110;
30×30 — 120;
20×40 — 125;
20×45 — 130;
40×40 — 140;
50×50 — 150;
60×40 — 160;
50×50 — 180;
80×40 — 240;
80×80 — 360;
100×100 — 480.

Cost may vary depending on market supply and demand.

Special devices for bending

In order to achieve high quality of the finished product, you can use factory-made and home-made devices.

Pipe bender

Pipe benders consist of a frame, several rollers, limiters and a drive. The device is controlled manually, by an electric motor and by hydraulic cylinders. In private construction, profile pipes with a wall height of up to 20 mm are used. A manual pipe bender handles their bending.

Conductor

This tool is designed for precise manufacturing and joining of profile joints when cutting with a grinder and connecting arches with vertical, transverse and inclined posts.

Thanks to the use of a jig, the most accurate connection of parts at right angles and a neat seam between them is achieved.

Making a bending machine with your own hands

We already wrote about how to assemble a manual pipe bender yourself in a previous article. This is not the simplest device, but it will allow you to quickly bend fairly large volumes of profiles. For assembly you will need 3-5 blanks for shafts, a channel, an I-beam, an angle grinder, a welding machine and a door with a set of fasteners. The photo below shows exactly the rollers we were talking about.

For today, that's all we have prepared for you. Share your bending methods in the comments and recommend our articles to your friends. See you!

Source: https://vseotrube.ru/montazh-i-remont/kak-sognut-profil-v-domashnih-usloviyah-bez-trubogiba

How to bend a profile pipe: all possible ways

Making metal structures with your own hands at home or in production often cannot be done without the use of curved elements.

The rounded shape of pipe frames is found everywhere in private construction: sheds, hangars, greenhouses, garden arches, benches, swings and much more. All this looks aesthetically pleasing and lightweight.

The most popular material for such structures is profile pipe; it is durable, lightweight, easy to install, and resistant to breakage and bending. Then the question arises: how to bend a profile pipe?

Bending a profile pipe: how to do it correctly?

The process of bending a profile pipe and a round one is not always carried out in the same ways; as a result, you can get a result different from the expected one. The square (rectangular) cross-section is difficult to bend, folds, cracks, breaks, flattening, axial twisting and other defects occur. To avoid this, let’s consider all the subtleties of the question: how to bend a profile pipe at home?

Before you begin bending, you should measure the internal height and wall thickness of the profile pipe. Due to the fact that the permissible bending radius of this range of products is not regulated, a value equal to the height of the inner wall of the profile minus twice the wall thickness is taken. These measurements are also necessary to determine the minimum permissible length of the bendable pipe section:

If the profile height (A) is up to 20 mm, the minimum bending area should be 2.5*A mm;
If the profile height (A) is more than 20 mm, the minimum bending area should be 3.5 * A mm.

Bending of a profile pipe along a radius is carried out taking into account the characteristics of the material and wall thickness. It is not recommended to bend tubular products with a large clearance and a wall thickness of up to 2 mm; flattening, creases, seam rupture and other deformations cannot be avoided. At home, it is better to use welding to form a bend.

https://www.youtube.com/watch?v=1OtJYlpg6Mk

When bending a square (rectangular) pipe with your own hands, the seam of the product must be placed on the side or on the convex side (not the concave side), so that the compression force does not directly act on the seam.

Ways to bend a profile pipe with your own hands

Owners most often cope with the arrangement of the territory around a private house on their own, building greenhouses, fences, gazebos, canopies, installing frames and structures from profile pipes. Such structures can consist of a large number of curved parts.

The service for forming the required bending of parts can be ordered at the enterprise, where, using a special pipe bender (profile bender), everything will be done quickly and efficiently. However, many people bending a profile pipe with their own hands turns out to be of no less quality and even without a pipe bender, which is expensive and will not be needed in the future.

There are several ways to do this at home.

How to bend a profile pipe using welding

Tubular products with a square or rectangular cross-section, the wall height of which is 30 - 40 mm or more, are difficult to bend, especially with small radii. To form a beautiful 90-degree bend from such material with your own hands, you cannot do without a grinder and a welding machine.

Procedure:

Make a bending template, which makes it easier to make several identical parts;
Use a grinder to make notches along the pipe along the three walls, leaving one intact. The more notches, the rounder the bend will be;
Fix one end of the profile securely;
Using force, grasping the second end, gradually bend the pipe according to the template so that the cuts form the concave part of the bend. The bending plane should not be disturbed; you can use a mallet;
Weld the cuts and grind the welding areas.

How to bend a profile pipe using fillers

The filler is used to obtain uniform bends without flattening and folds (corrugations on the concave part), filling the internal space, it distributes the compression and tension force over the entire surface of the bent section of the profile. The most tested filler is fine, dry, well-sifted sand.

This method may be accompanied by heating the pipe with a blowtorch or heating it with charcoal; when heated, the metal will acquire plasticity, which makes bending easier. Tubular products with a wall height of 30 mm or more are hot bent.

Pipe products with a wall height of up to 20 mm bend without heating, and with a bending radius of less than 50 mm, no filler can be used.

Procedure for the hot method:

Anneal the bend section of the prepared pipe;
Make wooden plugs in the form of pyramids 10 bases long, which are 2 times larger than the lumen, make 4 longitudinal grooves on one for gas removal during heating;
Plug one end of the pipe, gradually fill in sifted and calcined sand to the brim, compacting it by tapping. Cap the second end with a chopper with grooves;
Mark the heating area with chalk, clamp the profile, placing the seam not on the concave side relative to the template;
Heat the pipe until red hot, bend it with translational movements in one approach (re-heating is not advisable), observing the bend plane according to the template. Follow safety precautions;
After cooling, knock out or burn out the plugs.

With a wall height of up to 10mm, we can safely bend a profile pipe with our own hands without heating or filler. In other cases, instead of sand, you can use a steel spring with dense square or rectangular coils. It should be slightly smaller in size than the internal dimensions of the pipe, so that it fits tightly to the bend. The spring will also prevent unwanted deformations from forming during cold bending. They pull it out by the wire attached to the end turns, which goes out.

How to bend a profile pipe at home on a bending plate

This is another option for how to bend a profile pipe without a pipe bender, using devices you make yourself.

These include a horizontal metal or concrete slab with holes, a stationary flat template with a fixing element, and a workbench with a mandrel. These designs are good for cold bending of thin tubular products.

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The principle of operation is simple: one end of the profile is clamped, and the other is pressed under force, bending around the prepared shape. Manual bending requires considerable effort and does not guarantee accuracy.

It should be remembered that rolled steel pipes have a plastic moment of resistance (spring effect), so the bend must be adjusted several times to the template.

How to bend a profile pipe with your own hands and bring it back to its original shape is a difficult task. For everything to work out as planned on the first try, you can’t do without a special machine.

Pipe bender for products with square and rectangular sections

A roll forming machine is a device with shafts, one of which, with free movement under pressure, uniformly bends a pipe of the desired shape along its entire length. The shafts are machined to a specific cross-section. The pressure is applied gradually until the desired bend is achieved. The force is applied manually or using an electric drive or hydraulics. A home pipe bender is designed for a small number of bent products; a professional one can be used for serial bending of guaranteed accuracy.

Thanks to its design features, the profile bender qualitatively bends rolled steel pipes without heating, both in a separate section and along the entire length at different angles, in different planes.

It is also possible to make a bending device with your own hands; it will take a lot of effort, time and money, but the process of bending pipes will become easier. A manual profile bending machine is easy to use, has small dimensions, and can be installed in a garage or small workshop.

The pipe bender should be provided with a reliable, stable position; the work should be done slowly, constantly checking compliance with the template. The simplest option, suitable for thin pipes, is the Volnova roller machine.

In a certain place of a workpiece clamped in a vice, a bend is formed by a roller, but good physical strength is required.

How to bend a profile pipe at home is not an easy question. There are many nuances to consider and everything to be done correctly so as not to spoil the material. Much attention is paid to the cross-sectional dimensions, wall thickness, calculation of the bending radius, and it is also worth deciding whether to use heating, filler or not.

Source: https://www.0629.com.ua/list/74399

How to bend a profile pipe yourself at home without using a pipe bender

You don’t often encounter the need to bend profile pipes in everyday life. Owners of summer cottages or private houses most often find themselves faced with this task - people who are accustomed to doing everything with their own hands.

What is the difficulty of bending profile pipes?

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

From the point of view of physics, during the bending process, two multidirectional forces simultaneously act on the profile pipe:

Tensile force. Appears on the outside of the bend.
Compression force. Directed towards the inside of the bending area.

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

Different sections of the pipe in the bending zone may change shape differently, which will inevitably lead to a violation of their alignment.
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 get a crumpled metal surface instead of a smoothly curved pipe, you should definitely take into account the type of material and numerous geometric parameters of the product: wall thickness, cross-section diameter, bending radius. Knowing these characteristics will allow you to choose the optimal bending method.

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 the technology. For such pipes it is better to prefer welded joints.

The principle of using a pipe bender

It is not 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 drive wheel, which, moving along one of the edges, carefully bends the pipe section in the required direction.

There are two types of pipe benders:

Manual. The wheel of the device is operated manually using a special handle. Well suited for pipes with a small cross-sectional area.
Electrical. The use of such devices is justified in cases where the volume of work is quite large, and the pipes themselves have substantial dimensions. The device is connected to a standard power supply, and the wheel moves by means of an electric drive. Allows you to obtain smoother products with significant time savings.

If the work is one-time, purchasing your own pipe bender may not be profitable. In this case, you should consider renting the device, or consider one of the alternative bending methods.

Is it possible to bend a pipe at home?

If the pipe does not have the largest dimensions, and bending accuracy is not a critical parameter, it is possible to carry out the necessary work at home.

Of course, it will be better if there is a separate room for this work, equipped with a workbench, a vice and other necessary tools. In addition, during the work you will most likely have to use an angle grinder, a welding machine or an open flame source. Agree, a private house or apartment is not suitable for this.

Another important tip. Metal is a fairly elastic material that, after any deformation, will strive to regain its previous shape. For this reason, the pipe should be bent at a slightly larger angle than the design provides. The metal will return a few degrees back, and we will get exactly the bend radius that we originally expected.

To facilitate the bending procedure, the corresponding section of the pipe can be preheated. The hot metal becomes more ductile and pliable, which greatly facilitates the process. For warming up, they most often use:

gas burner,
blowtorch.

The pipe is thoroughly heated at the site of the future bend (the length of the heating site is taken to be equal to six pipe diameters).

We recommend that you familiarize yourself with: Manufacturing technology of profile pipes

It is worth remembering that repeated cycles of intense heating and cooling inevitably make the metal more brittle.

Alternative bending methods

Fortunately, you don't need any special equipment to bend pipes. People's ingenuity has long invented more than one way to achieve the desired result without using a pipe bender.

We use an angle grinder

In the area where it is necessary to bend the pipe using a grinder, several cross cuts are made. The smaller the bend radius, the more cuts will be needed. In most cases, three is enough. Next, the profile pipe is bent without much effort, and the cut points are sealed using welding.

If the welded areas are carefully sanded, the resulting product will look very decent . There will be no folds or significant loss of strength at the bend. But this method will not give ideal roundness, because the bend will consist of several straight sections located at an angle to each other.

Spring method

To make a spring you will need steel wire with a cross section of 2 mm. The wire is bent to the shape of the profile so that the side of each segment is several millimeters smaller than the corresponding side of the pipe profile and can move freely along its internal length.

Next, the spring is simply inserted into the pipe and bent to the required radius. To facilitate the bending procedure, the pipe section can be heated.

Note! To avoid problems with removing the spring from the cavity of the profile pipe after the bending procedure, a piece of wire should be securely attached to its nearest end.

Filling the pipe with sand

This method is striking in its simplicity and efficiency, because all the necessary materials are literally under your feet:

We first prepare two wooden wedges that can tightly close the pipe cavity.
We hammer the wooden wedge tightly into the end of the pipe.
We fill the pipe with sand, previously sifted and dried.
We drive in the second wedge.

We recommend that you read: Bypass valve and its role in the operation of the heating network

Next, one of the ends of the pipe is fixed and bent. To facilitate the procedure, the pipe section can also be heated. At the end of the work, the wedges are removed and the sand is poured out.

Using a dense sand bed will help prevent warping by ensuring an even and strong bend.

Plain water will help

One end of the profile pipe is closed with a plug, after which water is poured into the cavity. An indispensable condition is the presence of a negative temperature sufficient to freeze the liquid. After the water freezes, the pipe will bend without any problems, and the bend will be beautiful and durable.

It is important! The method is suitable for pipes made of non-ferrous metals that are not subject to corrosion.

Necessary equipment

To perform work on bending a profile pipe without using a special pipe bender, you will need one of these simple devices:

Elementary lever with a template.
A horizontal plate with several holes in which metal stops of the appropriate diameter are arranged. The device is well suited for pipes made of soft metals, or products with a low profile height (no more than 10 mm). Filigree precision cannot be achieved here. In addition, significant physical effort may be required.
Roller devices. One end is securely fixed in a vice, and a roller is applied to the bend, which, with appropriate physical impact, will ensure an even bend of the required radius.
Special mandrel. The device is a kind of template made of thick plywood or wood. With some effort, the pipe can be placed on the mandrel, giving it its bending radius. The device will be useful if it is necessary to frequently perform work on bending profile pipes.

Source: https://InfoTruby.ru/metallicheskie/sgibanie-profilnoj-truby

Profile types of pipes with a square or rectangular cross-section make it possible to construct a variety of structures that can withstand increased loads. When constructing a private building, you need to have the skills and knowledge of how to bend a profile pipe at home with your own hands, so as not to damage its integrity.

Main characteristics of profile pipes

The main feature of profile pipes compared to standard products is their cross-section. It is this difference that does not in all cases allow the use of standard bending methods to create the required radius of curvature.

In addition, industrial enterprises produce profile pipe products from a variety of materials, including copper, aluminum, brass, etc. This leads to the need to use different techniques in order to ultimately bend the profile pipe.

In the process of implementing mechanical influences in order to obtain a curved product, the pipe may receive defects and then during operation the integrity of the structure will be destroyed over time. For this reason, it is advisable to study the possibility of stretching it before bending the corrugated pipe.

To achieve the required bending radius when doing the work yourself, you should do it smoothly and leisurely and control the amount of effort applied. This will significantly reduce the likelihood of damage and obtain the required shape of the product.

The choice of how to bend a square pipe at home is influenced by the wall thickness of the pipe products. With a clear idea of what the final result should be and the correct approach to determining the bending method, the constructed structure will be distinguished by strength, reliability, aesthetic appearance and durability.

You should know that when the thermal effect is exerted on profile products, changes occur in the internal structure of the metal from which they are made. As a result, the strength and reliability of the structure may be in question. In addition, repeated attempts to bend a profile pipe with your own hands will lead to its destruction.

Using a pipe bender

It will not be easy to bend a profile pipe without a pipe bender or other similar devices at home, especially if the walls of metal products are large (read: “How to bend a pipe without a pipe bender - methods for different materials”). If you are planning a one-time job, then there is no point in purchasing a pipe bending machine. In this case, it is better to rent special equipment by contacting companies that provide similar services.

If you have to bend a profile pipe with your own hands, it is most appropriate and reasonable to use a pipe bender that has a special drive wheel. By moving along one of the edges, it allows you to bend the profile product as needed by the home craftsman in a particular case.

with manual control;
with electric drive.

When bending profile products is done manually, the device wheel is driven using a special handle. This method should be used in cases where the cross-section of the pipe has a small area, and the future design should not be bulky and its shape can be changed with your own hands.

For a large volume of work and the same size of pipes, you will need a pipe bender for a profile pipe, equipped with an electric drive, which is driven simply by pressing a button. The operating principle of this device is similar - the wheel moves along the edge of the pipe, but the result is more aesthetic and less labor-intensive.

Other methods of bending pipes yourself

There are several options that allow you to bend a profile pipe at home without special machines.

There are several requirements for bending metal products relative to a radius. The thickness of their walls must exceed 2 centimeters, otherwise bending can damage the integrity of the pipe. If the profile height (indicated by the letter Z) is more than 2 centimeters, a pipe bent over a length of 3.5xZ will not collapse and will not become less reliable.

An important role is played by the temperature that the product has when bending. It is known that it is much easier to give curvature to a pipe in a heated state. When carrying out work in domestic conditions, it is necessary to adhere to safety precautions.

To bend pipes with a profile height of up to 1 centimeter, it is not necessary to heat the products to give them a curved shape. But pipe products with a profile height of over 4 centimeters cannot be bent with your own hands without heating.

Using a grinder when bending profile pipes

In order for a bent profile pipe made by yourself to obtain the required bend radius, you can use a grinder.

In the place where the bend is planned, you need to make several transverse cuts (usually 3 of them will be required).
Then you should bend the profile pipe yourself.
Finally, the cut points are welded using a welding machine.

Since profile products have a regular cross-section, the resulting product should acquire an aesthetic appearance, provided that the welded areas are carefully ground. At the same time, the strength indicators will remain the same.

Bending profile products using a spring

This option is easy to implement, for which you will need to perform the following list of works:

They take a wire, preferably steel, about 2 millimeters thick, and make a spring out of it.
Next it is inserted into the pipe.
Heat the future bend area.
At the end of the work, the product is bent, observing the required radius.

You should immediately ensure that the profile pipe products are bent correctly, since the heated product retains its elasticity for a short time.

In the process of manufacturing a spring, you need to pay attention to this important point: its segments should be 1.5–2 millimeters smaller than the parameters of the corresponding side of the section that the profile metal product has. If you adhere to this rule, there will be no problems with inserting the spring inside the pipe.

Using sand to bend pipes

Source: https://moy-instrument.ru/masteru/chem-gnut-profilnuyu-trubu.html