Do-it-yourself pipe bender - simple drawings, diagrams, projects and the best homemade models of pipe benders (100 photos). How to make a pipe bender with your own hands: drawings, examples of creation and construction options Make a pipe bender drawings

It is necessary to pay attention to the mechanisms discussed in this article. To make a pipe bender for a profile pipe with your own hands, study the detailed instructions, videos, photos, drawings. Using these materials, it is not difficult to implement the corresponding project.

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Do-it-yourself pipe bender for a profile pipe: basic data

Before you study working documentation and algorithms for installation operations, the intended purpose of the product must be accurately determined. A pipe bender for a profile pipe with your own hands must be designed for certain forces, workpiece sizes, and materials. It is easier to establish meaningful criteria after familiarizing yourself with the parameters of devices tested in practice.

What are these devices for?

To create the necessary force, a lever mechanism is installed here. A metal pin is used to fix the free section of the pipe. It is installed in suitable grooves of the “comb” before performing work operations.

Using this factory sample as an example, it is easier to study the design features:

Handle (1) regulates the automatic stroke of the piston in the opposite direction. This solution reduces the burden on the user.
Installed inside the case hydraulic system. When the handle is moved up and down, a force of up to 150 kN is transmitted to the working piston (8). This is quite enough for quickly bending workpieces made of durable metals.
Support rollers (3, 4) are installed in the required frame holes open type(5, 9). They do not damage the surface, but provide reliable fixation.
This removable segment (6) is designed to be bent at an angle of 90°. But with the appropriate configuration, it can be installed on a similar product of a different shape.
The robust housing (10) is mounted on three supports (7). Rubber pads prevent movement during work operations.
In addition to cleaning from dirt, you should occasionally check the condition of the oil filter (11). No other regulatory procedures are needed.

In this technique, a workpiece of the desired shape is used. The pipe is pressed against it using a rotating roller and lever.

Important! Before bending a workpiece using a certain radius, you should study specialized reference books. They provide data on the permissible deformations of pipes made of different materials, with different wall thicknesses. If these instructions are violated, visible or hidden defects will form in the finished products.

Relatively small mechanical loads on working tools are created by levers and manual force. To work with durable metals, the equipment is equipped with hydraulics.

Making a pipe bender with your own hands for a profile pipe: drawings and other preparatory operations

A simple device for bending aluminum and plastic blanks is shown in this figure.

To make such a structure you need a strong one. After marking, a round profile is cut out of it. The remaining part is used to make the supporting element. The created parts are rigidly attached to the supporting surface. To ensure the strength of the connections, in addition to screws, clamps are used. Next, the pipe is bent by hand until the desired shape is formed.

Before creating this simple pipe bender for a profile pipe with your own hands, it is recommended to make a basic drawing with dimensions. A template made of thick paper or cardboard on which the markings will be applied will come in handy. It is clear that for the manufacture of more complex structures it is necessary to prepare complete design documentation.

It is not necessary to strictly adhere to engineering standards in order to make a pipe bender for a profile pipe with your own hands; a schematic image is quite enough. You just need to indicate all the dimensions, decide on the materials, technological process and components. The project will help solve several practical problems:

During the preparation process, it will become clear whether it is necessary to use other special equipment.
A complete list of necessary components will be needed for targeted visits to certain stores.
We must not forget that the machine must be protected from adverse external influences using wood impregnation, .
Some parts will be too difficult to make yourself. Appropriate orders should be placed in specialized workshops.

Important! Bending strong metal pipes requires a lot of effort. In order not to take unnecessary risks, you can use drawings of a proven design, or copies of an industrial design.

Making a manual homemade pipe bender for a profile pipe with your own hands: video and detailed instructions

Here we talk about how to quickly create a pipe bender with your own hands for a profile pipe (video).

The master used available materials, a channel, and part of the drive from an old bicycle. But he had to create the connections himself to ensure the integrity of the heavy structure.

To find out how to make a pipe bender for a profile pipe with your own hands, the drawings and videos are supplemented with descriptions of work operations. Below are the algorithms for several assembly technologies.

Rolling pipe bender

Drawing	Actions
	To create a high-quality one, you can use this drawing as a sample. Here the workpiece is placed between three rollers. The extreme ones (2) – perform supporting functions. To install them at different distances (to obtain required angles bending) grooves are made in the support strips (1). Required pressure created using a screw mechanism (6, 7). The force is transmitted through the central roller (4), which is rotated by the handle (5).
	The holes in the lower parts are created according to these dimensions. A channel with a wall thickness of 4 mm was selected for the workpiece.
	The upper part is created with cutouts. They must be made level so as not to interfere with the movement of the support screws.
	The thread is cut in accordance with this pattern.
	For the handle, you can choose a finished product, or use these sizes.
	Once assembled, you will get such a cute and functional product. There are no welded joints. But the components are difficult to make on your own without professional skills and specialized machines.

Hydraulic pipe bender

The screw mechanism performs its functions too slowly.

This design uses a standard jack. It is fixed rigidly to a bar, which is suspended on two springs. This solution simplifies manipulations with a heavy jack when installing workpieces and clamping segments.

The pipe rests on two round pins. They can be rearranged into other holes to create products with the desired radius of curvature. Parts of a durable steel frame (4-5 mm) are fastened with bolted and welded joints. The design turned out to be collapsible. If necessary, it is not difficult to dismantle it. The jack can be used for other operations.

Holes are created at the base of the frame. Through them the machine can be firmly attached to wooden floor nails, screws. This gives additional stability to the stationary structure. Its metal parts are degreased, coated and painted. In addition to a good appearance, it is ensured good protection from destructive processes.

For your information! When creating a homemade pipe bender for a round pipe, rollers, stencils and segments with a different shape of contact surfaces are used. The technologies used are the same as for bending profile products. The above drawings with appropriate modifications will be useful.

Article

Construction of greenhouses and sheds, laying engineering communications– all this requires the presence of a bent metal profile. But buying pipes bent to order is expensive, and purchasing a ready-made pipe bender is also not a cheap pleasure. So modern craftsmen use devices and self-made mechanisms to create metal arcs of the required radius.

In this article we will consider the following questions:

Types of homemade pipe benders and their features.
Design of the simplest pipe bending device square section.
Design of a three-roll machine for bending round and square pipes.
Technology for bending pipes using a three-roll homemade pipe bender.

Types of pipe bending devices and mechanisms

Nowadays you can find examples of pipe bending equipment that have different design: from relatively simple devices for manual bending to homemade machines with manual or electric drive.

According to their purpose, pipe benders are divided into two types.

The first type is angular (they allow you to give the desired radius to a certain area of the workpiece).

The second type is three-roll pipe benders - machines and devices that allow you to form a given bending radius along the entire length of the workpiece.

Depending on the method of adjusting the radius, pipe benders are mechanical.

And hydraulic.

The support shaft drive can be either manual or electric.

A simple device for bending metal pipes

The design of a homemade pipe bender depends on the volume and complexity of the work that is planned to be performed with its help. If the device is needed for one-time use (for example, for building a home greenhouse), then there is no need to create a complex three-roll mechanism with hydraulic adjustment of the bend radius.

belor44 User FORUMHOUSE

We urgently need to install a greenhouse. I want an arched one, but neither one based on metals nor my friends have a pipe bender. Build a pipe bender on shafts and rollers? There is neither time nor need for this. I think that a device for manual bending is suitable for one construction.

Yes, indeed, the simpler the pipe bender, the less hassle there is in its manufacture. The main thing is to correctly determine the dimensions of the device, which will directly depend on the bending radius.

Introducing a user-made device moning. It is designed to work exclusively with thin-walled pipes, because bending pipes by hand is hard physical labor.

Moning User FORUMHOUSE

I made this thing for a 30*30 square pipe. The radius that was obtained was approximately 1 meter. You can weld something like spacers or legs on the sides of the device so that it doesn’t throw from side to side when you press on the pipe. Regarding the jumpers at the bottom of the pipe bender: first, the pipe is placed under the top jumper (for the initial bend), then the pipe is placed under the next jumper (for further advancement).

Consistent bending is necessary so that if there is a sharp bend, the pipe does not break.

Calculating the dimensions of the device is very simple: to do this, it is enough to know the bending radius that you need to obtain on finished part. The strip (40 mm wide), which serves as a mandrel for the workpiece to be bent, initially has a curvature that provides a given bending radius (R).

Taking into account the presence of elastic deformations, the radius of the mandrel should be slightly smaller than the required bending radius of the workpiece.

Knowing how to use welding, grinder and auxiliary tools, this device can be produced in less than 1 day.

Each metal pipe has its own elastic limit, therefore, the bending radius cannot be reduced below certain values. Permissible minimum radii can be taken from the corresponding tables.

We present an example of a table of permissible radii for round pipes.

Minimum bending radii of pipes in a cold state

Pipe outer diameter, mm	Bend radius, min
	45	35	20	10
	R bend, min
18	74	62	56	43
24	95	79	65	55
32	115	96	79	67
38	156	131	107	91
50	197	165	136	115
60	238	199	165	139
75	280	260	194	173
80	324	270	224	190
90	362	302	250	213

Manufacturing of electromechanical pipe bender

In the design of an electromechanical pipe bender, three main working parts can be distinguished: one pressure and two support (drive) shafts. Hence the name of the machine – three-roll rolling pipe bender.

Such a device has quite complex design, therefore, if you were unable to get the drawings of a homemade pipe bender, we recommend that you first draw each of its elements on paper (at least in the form of a sketch). And we will tell you step by step what dimensions and characteristics the main components of the future product should have.

So, the main function of a pipe bender is to bend parts to a given bending radius. The bending radius depends on the distance between the support rollers (shafts) and is adjusted by the pressure roller. The distance between the support rollers is a constant value. This is what should be taken into account when starting to design a machine.

Alli58ru User FORUMHOUSE

The distance between the lower rollers depends on the minimum bending radius. When determining it, keep in mind that the smaller the distance between the rollers, the harder it is to lower the pressure roller and the harder it is to pass the workpiece between the shafts. And vice versa: the greater the distance, the easier it is to twist. For me, if memory serves, the distance is about 35-40 cm. The shafts rotate quite easily: I bent a minimum radius of about 50 cm, but less is possible.

The bend radius (arc radius) is calculated using a simple geometric formula.

Guided by it in relation to your equipment, you can quickly adjust the machine to the specified parameters.

Manufacturing of rollers

To make rollers, you should look for reliable materials that have already passed the strength test. Some use rotors from electric motors of old washing machines or kingpins from a KamAZ vehicle, others use carbon steel circles. In fact, there are many options, the main thing is not to forget that the chosen material must be strong enough. User Dva11, for example, used wheel hubs from an old sprinkler installation.

Dva11 User FORUMHOUSE

Hub diameter – 75 mm, length – 110 mm, bearings were selected according to the hub (205 fit). I had to buy 5 bearings and 1 pulley, and made the rest of the parts from scrap metal.

Smooth cylindrical shafts are a universal option. They are used to bend pipes of various sections. If the profile of the shafts is brought into line with the profile of the pipes being bent, the quality of bending will noticeably improve.

You can also use blanks designed for different profiles of bent workpieces.

Ideally, removable nozzles or ring clamps (limiters) are installed on the shafts, with the help of which the profile of the rollers is adjusted to the width of the pipe.

rusi45 User FORUMHOUSE

I made some improvements to the design of the rollers: I made attachments for the pipe on the outer shafts, where the stops are located. Tests were carried out on a 1 inch pipe. The attachments are easy to replace. To do this, I made one side of the bearings sliding. The nozzle is made of steel 65G (plus hardening). There is virtually no wear, and the file does not take hardness.

The internal radius of the roller or nozzle for a round pipe should be made with a margin: the radius of the pipe plus 1-2 mm. For example, if the pipe diameter is 24 mm, then the internal radius of the roller will be 13-14 mm. Only in this case the pipe will not jam during rolling.

This is the size we are talking about.

If the pressure roller intended for bending rectangular pipes, will have a small convexity in the middle, this will help maintain the geometry of the bent profile. The roller will press the upper wall of the pipe inward, preventing the workpiece from spreading out to the sides.

Frame design

Having decided on the center distance and the design of the rollers, you can mark the blank parts for the frame. Based on the experience of FORUMHOUSE users, it should be concluded that the strongest frames are made from steel channels (at least 80 mm wide). This material is easy to get, so you can safely take note of it.

The photo shows the machine at the manufacturing stage. And here is the drawing that is taken as a basis.

Human User FORUMHOUSE

During the work, some changes were made to the original drawings.

The presented drawing is not a mandatory guide to action, but provides an objective understanding of how a rolling pipe bending machine works.

Clamping mechanism

Many craftsmen make a clamp from a regular car jack (mechanical or hydraulic). The efforts that he is able to create are quite enough to give metal blank the desired configuration.

Profile bender design

The simplest option available to most novice craftsmen is bending pipes according to a pre-made template. This method is used when it is necessary to obtain a large number of blanks of the same type.

Bending a pipe according to a wooden template is the easiest way to solve the problem

As a template, you can use a structure made of wooden boards. The thickness of the wood is chosen based on the diameter of the pipes being bent - the board should have a margin of 2–3 cm. To prevent the metal profile from sliding off the template during work, the ends are processed with a slight slope.

The structure is attached to the floor or other surface in any way, installing a stop for the pipe nearby. Having inserted the profile into the gap between the template and the thrust element, smoothly and carefully press on its other end, pressing the pipe against the template. To ease the pressing force, you can use a lever of a suitable size or install a winch.

A winch can facilitate the process of bending pipes using a template

In a similar way, you can bend a metal profile of small diameter. If it is necessary to change the configuration of a pipe larger than 1 inch, then the template is made from sections of powerful fittings. To do this, holes are made in the concrete slab along the required trajectory, into which guides are inserted in the form of pins from sections of pipes, fittings, etc. The bending is performed by securing the edge of the metal profile by welding.

The advantage of this method is its cheapness and simplicity, however, the accuracy of the resulting blanks and the quality of their processing leave much to be desired. In addition, the template will have to be made every time you need to obtain a bend of a different radius.

Factory-made snail pipe bender

To produce a large number of similar workpieces with a small radius of curvature, you can use a snail pipe bender. This unit consists of two pulleys (wheels) different diameters, fixed on shafts. Having fixed the end of the pipe on the impeller, use a roller of a smaller diameter (drive wheel) to press the workpiece, simultaneously rolling it along the workpiece.

The most versatile and practical are homemade rolling pipe benders (bending machines), in which you can set any angle of deformation of rolled metal. The simplest design The rolling unit is a base with drive shafts fixed at a certain distance from each other.

Pressure on the pipe is carried out by a movable roller, and it is drawn through the rotation of the drive shafts. Screw devices, jacks, winches and electric motors are used as power drives for such devices. Rolling machine is the most difficult to replicate at home, as it requires turning and welding work.

However, there are many variations of its design made by amateurs, which indicates the high popularity of this solution. With the help of such a device, bending of any configuration is obtained, and the process itself is often automated. The only thing such a device cannot cope with is obtaining a minimum radius of curvature of a metal profile over a small segment.

The machine for bending profile pipes is structurally different from the usual one. This is due, firstly, to the greater resistance of the profile to bending loads, and secondly, to the fact that the bending radius usually required is large. Therefore, the design contains three rollers. Two of them are installed permanently, one remains movable.

The two outermost rollers are fixedly mounted on the body. They are raised above the plane of the base. For the middle roller, a special U-shaped frame is welded. A long, large-diameter clamping screw is installed in the middle of its jumper. A third bead is attached to the lower end of this screw (can be welded). By rotating this screw, the roller lowers and rises, changing the bending radius of the profile pipe.

A cloud is welded to one of the stationary rollers, with the help of which the pipe is rolled through the machine. To make it possible to apply less effort for rolling, two stationary rollers are connected using a chain. To effectively transmit torque, sprockets are welded to the rollers (possibly from a bicycle), and a chain is selected for them. Such simplest mechanism makes bending a profile pipe much easier.

In this design, the right or left roller is made movable. It moves along with part of the base. This part is connected to the rest of the frame using powerful metal hinges.

Drawing of a bending machine for profile pipes with a lifting platform

You can change the height using a jack, as shown in the drawing. The height of the platform in this case is selected depending on the height of the jack. The bending radius is changed by lifting the movable part of the table.

Unlike the previous design, this pipe bender for a profile pipe is driven from the central roller - a handle is welded to it. To reduce the required force, you can also weld the sprocket to two fixed rollers and transmit torque using a chain.

The base of the pipe bender is made from a channel or two welded angles. The thickness of the shelves is at least 3 mm; select the width of the shelves and the back of the channel to match the existing parts. One rule - the base must be massive and reliable.

Several holes can be made along the edges of the platform. Through them you can fix the machine to some heavy base using large diameter self-tapping screws. Fixation is necessary, since when bending pipes with a thick wall, significant forces have to be applied and it is more convenient to work if the machine is firmly fixed.

A few words about rollers. They must be made of good, high-quality, preferably hardened steel. It is on the rollers and on the axles that hold them that most of the load falls.

It should also be said about the shape of the rollers. They should not be smooth - there should be rollers along the edges that will prevent the pipe from “walking” during rolling. Only under such conditions will the arc from the profile pipe be smooth and not twisted. Ideally, each pipe size needs its own rollers. But then the design becomes more complicated - they must be made removable, and a reliable method of fastening must be thought out. The second option is to make videos complex shape, such as in the photo. Carve a few steps under different sizes pipes

In the same photo you can see that the upper part of the bed is not smooth, but toothed. With the help of such teeth, the rollers can be rearranged to different distances and thus also adjust the bending radius.

In general, homemade bending machines for profile pipes are assembled from what is at hand or what they can find/buy inexpensively. Those who have the opportunity grind out the rollers and insert bearings. Those who do not have such an opportunity use what they have - even bushings from bicycle wheels. In general, you need to understand the design and

Explanations and photos are good, but seeing the assembly process or the operation of the finished unit is much more useful. The first video shows the process of assembling (welding) a manual pipe bender for a profile pipe. The option with a movable middle roller was selected. The second video is about the operation of a simple pipe bender with a movable platform.

Roll benders come in various designs; in industrial settings, fairly large machines with electric or hydraulic drives are used; for bending small quantity products of small diameters - more compact manual or electric devices.

Universal production bending machine

The purpose of the roll forming machine is indicated by its name. This is the bending of metal profile pipes in order to obtain a certain radius of curvature in the required area or along the entire length of the workpiece. Using a profile bender, or pipe bender in other words, you can perform several technological operations with rolled metal of various types:

bending metal rods or reinforcement, including spring steel workpieces;
bending of profile metal products of square or rectangular type;
getting knees out round pipes or bending them at the desired angle;
rounding of parts of any length from rolled products (angles, I-beams, channels).

There are several models of bending machines. Some allow you to apply force only on a certain area of the workpiece. Others roll the pipe between rollers, applying pressure along the entire length. For some reason, it was the latter that received the name “profile benders” from experts, although both of them directly relate to the same type of equipment.

Rolling type profile bending

Depending on the type of drive, which, in turn, directly affects the power and productivity of the machine, profile benders are divided into several types.

Hydraulic driven roll forming machine. Powerful and very expensive

Hydraulic pipe benders are industrial equipment, therefore they have high power and are designed for permanent installation. Such units are used primarily in small-scale and serial production when it is necessary to obtain a large number of blanks of the same type. The hydraulic drive completely removes the load from the operator, giving him the ability to control the machine by pressing buttons.

What is a pipe bender used for?

Profile pipe is a hollow profile of square, rectangular, oval cross-section with a thin wall. Profile pipes are very widely used in construction, industry, mining, agriculture. Square and rectangular products are also used in everyday life: during the installation of metal structures, for the manufacture of furniture, garden buildings, sheds, greenhouses, fences, gazebos, awnings, pavilions, pergolas.

At the same time, steel has a certain plasticity - thin-walled pipes can be bent. But when bent, the pipe can bend, form kinks and folds - these defects reduce the strength of the pipes and do not look very aesthetically pleasing. Therefore, they are used for bending special devices– pipe benders.

When laying pipelines and manufacturing bent structures, bending allows you to minimize the number of welds and connecting fittings, which allows you to save a lot of money.

Making a rolling structure with your own hands

The use of a special tool that allows you to easily and simply bend pipes, including profile ones, can already be considered a plumbing tradition. Meanwhile, over the entire period of plumbing practice, a number of simplest ways to obtain bends without using a special tool have been invented.

Device drawings

Classification of profile benders

Pipe benders are classified according to the bending method and type of drive. In addition, pipe benders can be universal or specialized: for round or profile pipes.

The bending process itself can be hot or cold, with or without filling the inside of the pipe with filler (sand or salt).

Bending devices can be manual, hydraulic, electric, hybrid - combining molding elements with hydraulic and electric drives. There are industrial units for bending thick-walled pipes, in which the bending point is heated by induction.

Hydraulic devices are manual and stationary, which can bend workpieces with a diameter of up to 75 mm. Electrically driven units (electromechanical) can bend pipes of a wide variety of diameters. Electromechanical units can also bend thin-walled tubes with good quality bending, without folds or creases (see photo - it shouldn’t be like that).

Hybrid units are stationary, they have a hydraulic drive on part of the shafts, and an electric drive on the other part of the shafts.

Manual devices are used either as portable ones (they are used near the site where metal structures are assembled) or for bending small diameters or soft workpieces (copper, stainless steel, plastic). In a household plot or when working in an apartment, pipes of small diameters and in limited quantities are used, so at home it is enough to acquire a manual pipe bender.

According to the method of bending pipes, profile bending can be:

Roller - the workpiece is formed by passing between three rollers.
Crossbow - the workpiece is bent when placed in a special shape, according to appearance the design resembles a crossbow - hence the name. One device is usually accompanied by a set of molds for workpieces of various sizes and for various angles and bending diameters.
Segmented - the workpiece is bent by a special segment, while being stretched around the segment.

Lever – designed for manual bending thin-walled pipes.
Spring - used for copper or plastic pipes, a conductor spring made of thick wire is inserted into the workpiece (sometimes put on top) and manual bending is performed.

Mandrel - with filler (sand, salt) or mandrel installed inside the workpiece. The pipe is wound onto a winding roller; a mandrel or filler protects the bend from wrinkles.
Mandless - the workpiece is wound on a bending roller.

How to make a pipe bender for a professional pipe yourself

1st method

To make and use a bending machine for a profile pipe, you need to prepare two pieces of channel, two cuttings of fingers that are part of the tractor tracks, and four corners.

To bend the workpiece you will need a jack capable of developing a force of 5 tons or more. In this case, it will require its modernization by installing a steel platform on the retractable rod, for the manufacture of which a worn-out pulley can be used, having a “stream” width comparable to the pipe profile.

The frame of the future machine is assembled from corners fixed to a steel plate by welding. A total of four corners are used, having a flange from 60 to 80 mm, at the upper ends of which two channels are fixed by welding. To adjust the bend angle, it is necessary to have symmetrical holes in the walls of the channels that need to be drilled.

To bring the finished machine to its starting position for work, it is enough:

insert the axles (fingers) into the holes obtained in the channels and fasten the rollers to them as stops for the workpiece;
raise the jack platform to such a level that the workpiece can pass into the gap formed;
install the workpiece in the machine for the profile pipe and create the required bend using a jack, using its functionality.

2nd method

A homemade pipe bender for a rolled profile pipe implies that the workpiece will be laid on side rollers and pressed on top by a third one. After fixing the pipe in this position, all that remains is to drive the shafts through a chain transmission to achieve the desired bend.

To make a machine for rolling profile pipes you will need:

Attention! It is problematic to manufacture a functional rolling pipe bender without the appropriate calculations and drawings. However, not everyone has the necessary knowledge for this, so it is best to use ready-made documentation.

Making your own pipe bender for a profile is a completely feasible task that must be correlated with certain goals. If you plan to carry out such work only as a one-time event, then you can assemble a wooden structure that is quite capable of withstanding short term operation.

To assemble a stationary device required for bending pipes, you must do the following:

mount a metal frame, connecting its elements using bolts and welding;
install the axles and shafts on them in accordance with the existing drawing, observing the placement levels: two above the third;
assemble the chain drive used to power the machine, which will require not only a chain, which can be borrowed, for example, from an old motorcycle, but also three gears;
attach a handle to one of the shafts.

You can make the simplest profile bending machine yourself. This work is quite within the capabilities of a home handyman. The quality of homemade products is practically not inferior to industrial designs. The performance, of course, differs from models with an electric drive, but the house and estate do not require a huge number of bent products.

Drawings and diagrams

Regardless of how you decide to make a pipe bender, you should first consider the scope of its application - decide what size and shape products you will bend, and with what bending radius. For garden structures and furniture, the bending radius can be 2.5 sides of the section (for round blanks - 5 radii), or it can be 10-15-20 sides (for gazebos, greenhouses and other large structures). Then draw a drawing or diagram with exact dimensions. Without a drawing it is impossible to assemble a high-quality pipe bender.

The simplest pipe bender- a template cut from boards, stuffed onto a base - thick plywood or OSB. Rolled steel is bent by hand. The thickness of the boards should be greater than the diameter or side size of the workpiece - then the bending will be of better quality. You can make a template from steel pegs or hooks driven into a solid base (preferably concrete).

It is enough to simply assemble a manual Volnova machine for profile workpieces. A roller with a radius is fixed to a strong metal plate, equal to the radius bend, and two metal plates with a second roller attached. The end of the pipe is clamped with a clamp, the roller on the plates rotates and bends the workpiece.

There is another version of a profile bender that you can make yourself - with three rollers.

To make pipe bending rollers or a rolling pipe bender you will need:

Metal frame (bed) made of rectangular channel.
A durable stand welded from square profiles, channels, angles, or a stable steel workbench.
Three rollers with shafts; the rollers must be turned in such a way that a groove is formed in them with dimensions equal to the dimensions of the bent profile; shafts and rollers are ordered from a turner.
Shaft bearings.
Chain.
Winch.
Clamp.
Corners for guides.

Tools:

Grinder with cutting discs.
Welding machine, electrodes.
Dye.
Electric drill.
Shaft mounts.

The frame is secured to a stand or workbench - welded to the stand, secured to the workbench with clamps. The guides are welded. Bearings are mounted on the frame, two lower shafts are mounted in the bearings, and rollers are mounted on the shafts. Shafts and rollers are ordered from a turner.

A double-row chain is put on the shafts, a winch is secured in the middle, and the chain is secured. The pressing movable shaft is secured. The upper pressure roller and shaft move along the guide using a screw.

Purpose and types

A pipe bender is an indispensable device when you need to delicately and accurately bend a round or profile metal pipe

The bending of metal profile pipes is directly related to their diameter, wall thickness and material of manufacture, therefore metal manufacturers always indicate the minimum radius of deformation in special tables.

Calculation table for bending radii of steel pipes depending on diameter and wall thickness

Special devices - pipe benders - allow you to obtain a bend of the required curvature without damaging the part. Depending on the length of the fragment that needs to be bent, two types of devices are used:

lever pipe benders;
rolling units.

The most common products are pipe benders lever type. In such devices, the force is applied in in the right place, and the bend itself repeats the shape of the segment (template), which in some devices can be removable. As a rule, such units include several segments for pipes various diameters.

In addition to segmental devices, the industry produces mandrel and crossbow pipe benders, the bending shape of which is set by two guide rollers and a pressure template (mandrel). This design allows cold processing of round steel pipes in short areas. By the way, compact crossbow pipe benders are the most popular tool among utility installers.

Simple, fast and high quality - these are the advantages of crossbow pipe benders that attract professional installers

Depending on the design of the lever bending device, it can have any type of drive:

hydraulic;
pneumatic;
electric.

The need to bend profile pipes in household arises quite often, whether it is preparing blanks for construction metal frame greenhouses or canopies or the manufacture of pipeline parts of complex configurations. For this, industrial-made devices are often used, but purchased products are not cheap. It is much more profitable to make a pipe bender with your own hands, especially since the manufacture of the unit does not require any scarce parts, and its design can be repeated in any garage. A homemade device will allow you to obtain a pipe with the desired radius of curvature and at the same time avoid deformations and creases on its surface.

Purpose and types

A pipe bender is an indispensable device when you need to delicately and accurately bend a round or profile metal pipe

Calculation table for bending radii of steel pipes depending on diameter and wall thickness

It is not easy to bend a hollow pipe without creases and deformations. At home, to do this, fill it with sand and heat it until it turns red. gas burner or a blowtorch, after which they bend “by eye”. Of course, this method, although labor intensive, is not ideal due to low quality and low accuracy.

lever pipe benders;
rolling units.

The most common products are lever-type pipe benders. In such devices, the force is applied in the right place, and the bend itself follows the shape of the segment (template), which in some devices can be removable. As a rule, such units include several segments for pipes of various diameters. In addition to segmental devices, the industry produces mandrel and crossbow pipe benders, the bending shape of which is set by two guide rollers and a pressure template (mandrel). This design allows cold processing of round steel pipes in short areas. By the way, compact crossbow pipe benders are the most popular tool among utility installers.

Simple, fast and high quality - these are the advantages of crossbow pipe benders that attract professional installers

Depending on the design of the lever bending device, it can have any type of drive:

hydraulic;
pneumatic;
electric.

Often the operating principle of the unit involves heating the pipe (externally, or with the help of heated air passed inside the rolled product), thereby increasing its ductility, and, accordingly, the quality of the bent section.

If it is necessary to obtain a bend of a large radius, rolling devices are used. Their design includes two guides and one pressing shaft (rollers). The pipe is pulled between the moving elements, setting the degree of bending by the force of the pressure roller. If it is necessary to obtain a large radius of curvature of the workpiece, the procedure is repeated.

Rolling attachments may have an electrical drive for the guide shafts, as well as a hydraulic, mechanical or pneumatic drive for the pressure roller.

Designs of homemade devices

The simplest option available to most novice craftsmen is bending pipes according to a pre-made template. This method is used when it is necessary to obtain a large number of blanks of the same type.

Bending a pipe according to a wooden template is the easiest way to solve the problem

As a template, you can use a structure made of wooden boards. The thickness of the wood is chosen based on the diameter of the pipes being bent - the board should have a margin of 2–3 cm. To prevent the metal profile from sliding off the template during work, the ends are processed with a slight slope.

A winch can facilitate the process of bending pipes using a template

In a similar way, you can bend a metal profile of small diameter. If it is necessary to change the configuration of a pipe larger than 1 inch, then the template is made from sections of powerful fittings. To do this, holes are made in the concrete slab along the required trajectory, into which guides are inserted in the form of pins from sections of pipes, fittings, etc. The bending is performed by securing the edge of the metal profile by welding.

Factory-made snail pipe bender

To produce a large number of similar workpieces with a small radius of curvature, you can use a snail pipe bender. This unit consists of two pulleys (wheels) of different diameters, mounted on shafts. Having fixed the end of the pipe on the impeller, use a roller of a smaller diameter (drive wheel) to press the workpiece, simultaneously rolling it along the workpiece. As a result, the pipe bends around the surface of the large pulley, repeating its shape. The only drawback This method is the impossibility of obtaining roundings of large radius.

The most versatile and practical are homemade rolling pipe benders (bending machines), in which you can set any angle of deformation of rolled metal. The simplest design of a rolling unit is a base with drive shafts fixed at a certain distance from each other. Pressure on the pipe is carried out by a movable roller, and it is drawn through the rotation of the drive shafts. Screw devices, jacks, winches and electric motors are used as power drives for such devices. The rolling machine is the most difficult to replicate at home, as it requires turning and welding. However, there are many variations of its design made by amateurs, which indicates the high popularity of this solution. With the help of such a device, bending of any configuration is obtained, and the process itself is often automated. The only thing such a device cannot cope with is obtaining a minimum radius of curvature of a metal profile over a small segment.

Video: Homemade rolling bending machine

Making a pipe bender with your own hands

To make a pipe bender, you can use drawings of finished structures. After looking at several options and balancing the complexity of the units with your capabilities and availability necessary details and materials, you can choose the most optimal scheme. For your consideration, we present two models of pipe benders for self-assembly- a manual unit for small pipes and a semi-automatic bending machine.

Manual snail pipe bender for small radii

To correctly bend a profile pipe, you need to have a good understanding of the physics of the process. Manual pipe benders most often use a circular bending method, which avoids the risks associated with bends, cracks and other damage to pipes. To bend rolled metal in such a unit, it is enough to secure the workpiece in the device and press the lever. Bending occurs when a roller is rolled along the pipe, pressing the part to the main wheel.

Materials and tools

To make a manual pipe bender you will need:

metal sheet with a thickness of at least 6 mm;
Working wheel;
pressure roller
steel corners 50x50x2.5 mm;
a piece of thick-walled pipe Ø25 mm;
axes of rotation (sleeve or bearing assembly);
a piece of square rod 20x20x40 mm;
nuts and washers;
angle grinder;
welding machine;
hammer;
measuring tool.

While working, do not forget about safety precautions. This is especially true when working with cutting and welding equipment.

Pipe bender calculation and drawing

Before you start work, you need to decide what bending radius of profile pipes will be most in demand. Depending on this, the size of the impeller is selected. It is this value that will correspond to the inner radius of the resulting elbow.

Snail pipe bender assembly

The drawing is designed for profile pipes with a diameter of up to 1 inch. The bending radius that can be obtained with this pipe bender is 125 mm (half the diameter of the impeller). If you need a bending unit with other parameters, use the method for calculating the dimensions of a pipe bender.

The main size of the pipe bender fork is the distance between the axes of the impeller and the roller (indicated by the letter a=200mm). In our case, the center distance is chosen taking into account maximum size processed profile pipe d = 25 mm, however, it is advisable to add a couple of millimeters “in reserve” to this value.

The center-to-center distance can be determined by the formula a = d + r1 + r2 + 2, where d is the diameter of the profile pipe, and r1, r2 are the radii of the impeller and roller, respectively.

If a roller and a wheel with a groove (some kind of rivulet pulley) are installed in the design of the bending device, then the measurement is carried out starting from the lowest point of this part.

Snail pipe bender fork

To determine the size of the fork, the gap between the roller and its base is taken equal to 10 mm, and a 30 mm margin is also added for attaching the impeller axis.

Fork length c = a + r1 + 10 + 30 (mm).

To determine the internal clearance between the fork side flanges (b), add 1 - 2 mm to the wheel thickness.

You can make the pipe bender more versatile by drilling several holes in the side surfaces of the fork. By rearranging the roller axis, the distance between the working surfaces of the rotating parts is changed.

Step-by-step instructions for making a manual pipe bender

The drawing of the manual bending unit shows that it consists of several main parts:

base in the form of a thick metal plate;
Working wheel;
video clip;
fork.

Our instructions will help you perform the work consistently, avoiding errors and inaccuracies.

Make an impeller and roller. Of course, a huge advantage would be the presence lathe in your workshop, but even if you do not have such equipment, these parts are not a problem. Any turner can turn pulleys at a very reasonable cost.
When manufacturing moving elements, you should not save. Be sure to make a groove in them for a pipe of maximum diameter, and also carve a seat in the roller for any suitable rolling bearing. If there is a need to change the configuration of the elbow surface, the groove of the impeller or roller is made shaped. When rolling, the roller will leave the required imprint on the outer surface of the knee, and the wheel on the inner surface. To make the turner’s task easier and further reduce the cost of the device, instead of a roller, you can install a pair of ball bearings of a suitable size.
Pipe bender impellers can be manufactured with a trough of any configuration
The image clearly shows the ball bearings installed instead of the roller
On the same machine it is necessary to make axles for the impeller and roller. The thickness of the parts is taken equal to the inner diameter of the selected bearing. The length of the axle for the roller is equal to the width of the fork along the outer dimensions. The axis of rotation of the impeller will be slightly longer, since you will also have to take into account the thickness of the base plate of the pipe bender. By refusing to install bearings, the design can be significantly simplified. In this case, long bolts with nuts can be used as axles. However, it should be understood that bending pipes with this device will be more difficult.
To make a fork you will need metal with a thickness of at least 6 mm
Cut from sheet metal side surfaces and the rear wall (base) of the fork, as well as a piece of thick-walled pipe as a lever.
According to the drawings, holes are drilled in the fork for the axles of the wheel and roller.
Weld the fork parts. Special attention should be given to all right angles of this structural element.
Attaching the lever to the fork end-to-end will be unreliable due to the large force applied. It is best to make a hole in its back wall into which the edge of the pipe will fit. By scalding this joint by welding, the most durable joint is obtained.
Using a grinder, cut out the base (frame) of the device and drill a hole in it for the stationary axis of the impeller.
If necessary, a bearing is pressed into the roller.
The roller is inserted into the fork and then secured with welding or nuts.
Snail pipe bender fork assembly
The fork assembly is installed on the base, securing the impeller axis in the same way as when installing the roller.
Weld a square section piece as a clamp for the pipe being processed.

Holes are drilled in the corners of the base of the pipe bender to attach the device to the workbench. In order for the device to be not only functional, but also aesthetic, during the work process, be sure to clean the weld joints and use a grinding wheel to process the sharp edges of the workpieces. To protect against rust, the finished product is painted with enamel.

Bending machine for profile pipes

Bending long profile pipes requires not only force to deform them, but also a mechanism to pull the parts to the required distance. Often, the design of homemade bending machines uses not a screw, but a jack or winch, and the drive includes an electric motor.

Drawings of homemade devices

Bending machine. Side view Pipe bender with top roller drive Pipe bender with variable distance between rollers
The simplest broaching type pipe bender

In the bending machines shown in the drawings, a threaded drive is used to press the roller. In our design we will use hydraulic jack, as well as manual drive using parts from the gas distribution mechanism of automobile internal combustion engines.

Tools and materials

To get started, prepare the following parts and materials:

corners for the machine bed;
round or profile pipes for the frame;
working and broaching shafts (rollers);
jack;
springs;
chain transmission;
tensioner;
bearing supports assembled with bearings;
pen;
channel for fastening;
bolts and nuts.

For work you will need hand and electric plumbing tools:

angle grinder (grinder);
welding machine;
electric drill and set of metal drills;
hammer;
set of wrenches;
measuring tool.

Don't neglect your resources personal safety. When working with an angle grinder, be sure to use a protective shield or goggles, and carry out welding processes in thick overalls and special gloves. It should be remembered that it is prohibited to work without a welding helmet and carry out electrical installation work on a wet surface or in the rain.

Instructions for making a bending machine

Dividing the pipe bender manufacturing process into several stages will help organize the work more clearly.

Make broaching (support, drive) and pressure (working) shafts. If you do not have the skills to operate a lathe, you will have to contact a specialist. Be sure to remind the turner to machine the rollers with shanks for installing the sprockets. It's best if you take these parts with you.
The design of the operating shafts must provide for the possibility of installing drive sprockets
Any sprockets and chain can be used. For example, from the gas distribution mechanism of passenger car engines.
Attach the bearing supports to the shafts and install the drive gears on the keys.
The design of the machine can use drive sprockets and bearing supports from automotive equipment
Make with welding machine bending machine frame. To do this, first make a square frame with support legs, and then mount a structure on it, along which the plate with a pressure roller will move.
Making a bending machine bed
A steel U or H-shaped channel is used as a plate. To install the pressure shaft, holes are drilled along the edges of the plate according to the connecting dimensions of the bearing supports.
Making a frame for installing a base plate
A section of channel with a roller is suspended from the upper part of the frame on four springs, for which nuts are welded at the corners of the plate and frame as mounting loops. After this, a hydraulic jack is installed.

When setting up a household, sooner or later you are faced with the need to bend a pipe. In a city apartment - less often, but also. The prices for pipe bending tools and accessories, both for sale and for rent, are not exactly exorbitant, but, to put it mildly, they are not encouraging. Therefore, there are more than enough people who want to make a pipe bender with their own hands, and the purpose of this publication is to help them find a design suitable for their specific purpose and give effective practical recommendations for its manufacture.

Amateur craftsmen make a wide variety of installations for bending pipes, from simple devices to real bending machines, see figure:

But a considerable part of homemade pipe benders bend according to the principle “as it happened, so it will be.” At the same time, those who happened to see the insides of an airplane or rocket probably noticed the bundles and intricacies of pipes, bent, sometimes in the most bizarre way, cleanly and evenly “just like it was.” But no “highly cosmic” secrets, respectively. production equipment No. At aerospace factories, pipe bending is done by low-level workers or even apprentices. The secrets lie in the correct proportions of some of the manufacturing features of pipe bending machines and devices and in choosing the right one for certain work their type. In this article, these “secrets” are revealed, with an emphasis on a pipe bender for a profile pipe, since, on the one hand, it is professional pipes that are most needed in private households, and on the other hand, their bending is much more difficult than round ones.

Note: further in the article cold flat production-technological and, in part, decorative-art bending is considered. So, if you are eager to set up mass mechanized production in your own barn, well, say, hyperbolic coils for moonshine stills, then - see somewhere else.

Bending defects

At military councils, it is customary first of all to report on the enemy. So we will begin our debriefing with what needs to be avoided.

Typical pipe bending defects are shown on the left in the figure:

For household and other pipelines general purpose Tightness and wave are acceptable, which together reduce the lumen area of the pipe by no more than 10% at the narrowest point. On pipes for gases and refrigerants, any stretch and, especially, a wave, are undesirable, because There may be microcracks there. A wave, even a small one, is unacceptable in tubular power elements of building structures and mechanisms, since it sharply and unpredictably reduces their load-bearing capacity.

A characteristic defect in bending rectangular corrugated pipes is a “propeller” (in the center in the figure), when the pipe twists along its axis during the bending process. An arch or semi-arch that is bent with a “propeller” is most often impossible to fix until it is suitable for use. The reason for the “propeller” is the asymmetrical distribution of technological loads during bending, and bending equipment for profile pipes must ensure their correct spreading over the workpiece.

Another characteristic defect, but of round thin-walled pipes made of soft metals (copper, aluminum) is a “bun” (on the right in the figure), an external and/or internal longitudinal scar; Most often, the flattening of the pipe is noticeable to the eye, hence the name. There will definitely be a microcrack in the “bun” somewhere. A chronic leak in the house water supply or an air conditioner losing freon is not a cheap “fix”, but a leak from the fuel pipeline is simply dangerous. Building construction, including tubular elements with a “bun”, are prone to sudden destruction. The reason for the “bun” of bent pipes is the incorrect choice and/or setting of a pipe bender.

Main rules

The rules for choosing the bending radius of the pipe R IZG and the length of the technological shank L are summarized in the table:

The “tail” is needed at the beginning of the bend, i.e. the pipe is fed into the pipe bender with some excess at the outlet. The R values of the IZG are calculated for defect-free bending. If permissible defects(see above) are acceptable, then R IZG can be reduced by one step. way:

If the difference between the real and the nearest tabulated values of the pipe diameter P is more than 10%, the values of the initial calculated values are calculated by interpolation. Otherwise, we take the nearest one.
The tabulated R IZG is reduced to the relative value r IZG, i.e. It is expressed in pipe diameters D or heights H.
For pipes with a diameter of up to 10 mm, 1 is subtracted from r IZG.
For pipes with a diameter of 11 to 15 mm, 0.85 is subtracted from r IZG.
For pipes with a diameter of 16 to 24 mm, 0.75 is subtracted from r IZG.
For pipes with a diameter of 25 to 40 mm, 0.65 is subtracted from r IZG.
For pipes with a diameter of more than 40 mm, 0.5 is subtracted from r IZG.
Convert the relative r IZG back to the numerical (millimeter) R IZG.
From the obtained value of R IZG, take the nearest practically convenient larger one.

Example: need to bend out steel pipe 24x24x1.5, i.e. already classified as thin-walled, complex semi-arches for a flower house or hut. The structure is non-residential, light, complex semi-arch load-bearing structure is not (see below), i.e. "plumbing" wave and taffy are acceptable. We take data for the pipe H=25. According to the table we find r IZG = R IZG /H = 80 mm/25 mm = 3.2. Subtract the correction (for pipe H=25!): 3.2 – 0.65 = 2.55. Convert back to millimeters (again according to the table H=25!): 2.55x25 = 63.75 mm. That is, if we take a new bending radius of 65 mm instead of the “defect-free” 80, then the selection of bending devices and work will be simplified, the possibilities of artistic expression by the shape of the structure will increase, and there will be no visible and/or dangerous defects in the finished structure.

Note: for some types of pipe bending devices, e.g. mandrel and 3-roller, see below, the initial (starting) “tail” does not seem to be needed. But his role in in this case the not yet bent remainder of the workpiece plays a role, so it is impossible to cut the original pipe to exactly the size in advance, otherwise it will be defective. A cut for a single “tailless” product, for example. a curl for cold forging, cut in stock for the “back tail” the same as the “front”. The stock goes to waste, so it is better to bend products without straight sections at the beginning and/or end in batches sequentially from one pipe, then only the very last “tail” will go to waste.

Simple - radius

A specific pipe bender is designed for a bend radius within certain limits. But to select a design prototype, you immediately need to know only its very general meaning:

for small radii R IZG<5D (или 5H);
for medium radii 5
for large radii 20D(H)

How to bend?

This refers to bending quality factors:

Clean (defect-free) or not – whether acceptable defects are acceptable.
For pre-installation - distortion of the bending profile is not significant, as long as it fits in the trench/groove/on supports. The “tails” (straight ends) of the curved section are cut to size, i.e. A section of pipe for bending is cut with a reserve that goes to waste.
True to size - distortion of the profile is also not significant, but the “tails” during installation must fall into place with the specified accuracy. This is how pre-measured parts of pipelines are bent from expensive materials: copper tubes for lowering gas pipelines, parts of split-system air conditioners, tubular parts of production equipment. For example, some exclusive liqueurs are produced in distillers whose vapor-liquid path is silver.
According to the profile for additional installation - the bending profile is maintained with the specified accuracy; Can be adjusted to fit by hand. Bending is done with technological “tails” for cutting in place. Building structures, decorative details of architectural forms.
Profile-to-size – parts made of valuable metals of production equipment, instruments, machines and mechanisms, which during installation must fit immediately into place or with minimal adjustment within precisely established limits.

What to bend?

I mean, what kind of curves do you need? This is the second factor that determines the type of pipe bender needed for the job.

In the household sphere, most often there is a need for a trace. types of pipe bends (see also Fig.):

General purpose – various kinds of distribution pipelines, ventilation devices, wire communications inputs, parts of production equipment, machines, mechanisms, etc. Bending most of all to size or for additional installation in small quantities; less often - along average radii. Acceptable defects in parts of water pipes and inlet devices are acceptable. Bends of parts of gas and steam pipelines, parts of technical devices are defect-free by default, unless otherwise specified in the specifications for the product.
Building arches are tubular curved parts of building structures that can bear operational loads for a long time without the danger of sudden destruction. Bending almost exclusively according to the profile to size along large radii, occasionally - along medium ones. In private household plots, the most popular type of this kind of parts is arches made of corrugated pipe for greenhouses and other outbuildings. Of the permissible defects, taffy is acceptable in no more than 5% of the cross-sectional area of the pipe lumen.
Architectural forms - the bending radius is alternating (in one direction or the other) from small to large. Due to the “dips” in the bending profile, the load-bearing capacity is much lower than that of building arches of comparable sizes. For the same reason, sudden destruction of a non-worn part is possible. Bending – according to the profile for pre-installation; rarely - in size. Scope of application light non-residential structures for landscape design: gazebos, alcoves, flower corridors and tunnels, decorative trellises, fences, etc. In the designs of residential and temporary inhabited structures they are used only in conjunction with additional load-bearing elements. Acceptable defects are acceptable, most often even on 20-25% of the lumen area.

Prototype selection

Based on the entire complex of the above indicators, a pipe bender of a certain design is selected. Among those available or partially available for self-production are devices, tools and machines for bending pipes:

manual bending lever– bending round pipes with walls of normal thickness to medium and large radii. Thin-walled pipes flatten and crumple; on profile ones, a “propeller” appears when the lever is slightly swung to the side. It certainly produces acceptable defects. Bend for additional installation or, with an additional control template, along the profile for additional installation. Simple, cheap, non-volatile. No permanent production area is required for placement. Mobile: can be carried manually over long distances. Low productivity, high bending labor intensity and worker fatigue. Quite high demands on the operator’s physical strength, qualifications, endurance and conscientiousness. Scope of application – single non-standard parts of building structures;
bending plate (board)– similar to a lever, but for small and medium radii. Manual mobility is limited to the construction site. Productivity is higher, and labor intensity, fatigue and the required qualifications of the worker are lower than for a lever. Prem. applies. during construction work for the on-site production of parts of pipelines and tubular inlet and/or ventilation devices;
bending template (conductor)– has properties similar to those of a bending lever, but is intended for bending thin-walled, soft metal and profile pipes. Defect-free bending according to the profile to size is possible. Very low productivity (especially for steel pipes) due to “sludge” for metal relaxation, see below. If there is no hurry (say, in winter before the summer construction season), a roller pipe bender can replace it. It is also possible to produce multi-radius architectural forms (with a counter-pattern). The required qualification of the worker in metal processing is initial;
roller (rolling) pipe benders– manual bending of pipes up to 30-40 mm along a radius profile for pre-installation and to size. Bending radii are small. The complexity and labor intensity of manufacturing are low. A separate production area is not required; operator qualification requirements are minimal. Productivity is low. Defect-free bending of thin-walled soft metal pipes is possible. Mobile manually. Prem. scope of application – general purpose bends (see above) during plumbing and repair and construction work. The complexity and labor intensity of self-production is low;
crossbow (crimp) pipe benders– similar in properties to roller ones, but with increased performance for round pipes made of soft metals with walls of medium thickness. Rapid reconfiguration is possible during work. They are mobile to a limited extent (transported by road) or installed permanently. Self-production is not justified, see below. Most often used in the installation of home and apartment copper and aluminum pipelines. In production conditions - for making general purpose bends on steel pipes with a diameter of up to 60 mm;
mandrel (bypass) pipe benders– also similar to roller ones, but bending with a variable radius is possible without a starting shank. The requirements for the employee's physical strength are quite high. The main purpose is the production of small fragments for architectural and decorative purposes and for artistic forging. The complexity and labor intensity of manufacturing on your own is very high.
roller (rolling or broaching) pipe bending machines– high-performance bending of any pipes along large and medium radii. Installed permanently in a specially prepared room or on an equipped site; less often, they are transported to the place of work. Bending – defect-free in profile; perhaps - according to the profile in size. The main purpose is the production of radius construction arcs from corrugated pipe up to 80 mm wide.

Description of designs

The material presented above is sufficient for preliminary selection of the design of the pipe bending equipment required for this specific job. To clarify the final solution, we provide more detailed descriptions.

Lever arm

The design of a manual bending lever couldn’t be simpler, see fig. However, such a primitive device for centuries and millennia bent details that sometimes baffled modern technologists. The pipe can also be laid simply on the ground by placing wooden blocks under it and securing it with staples driven into the ground. It is better to work with a lever with an assistant holding the workpiece, checking during bending against a pre-prepared template.

Plate

The bending plate (support-thrust manual pipe bender) has been known for as long as the lever. The design is in some way ingenious: the bending pipe itself is used as a bending lever, and instead of a “hole” (a clamp on the lever), its opposite is a strong support pin or several of them. In general, everything is according to Murphy’s laws: if it doesn’t work out as it should, try doing it the other way around.

The structure of the bending plate is clear from Fig. (left):

Bending plate (support-thrust manual pipe bender) and its “ground” modification for the manufacture of greenhouse frame arcs

The most common variety is 4x4. All common bends can be made on the slab for retrofitting (with acceptable defects). Interfering stops are simply removed; the missing ones are substituted. The installation pitch of the support pins is taken so that the thickest pipe used fits between them. A concrete slab can be poured directly onto the ground in some inappropriate place on the construction site, for example. where the foundation of the shed will be (inside, not under the tape!) or, say, a cesspool. Brand of ready-made solution – from M250; reinforcement is at least 2-tier. The holes to the pins are formed with wooden sticks, wrapped in film or generously greased with grease (worse). Pins for a concrete slab must be made with shanks as long as the thickness of the slab; You can also use simple round pins from sections of thick-walled pipe or steel rod.

The “earth” modification of the bending plate is shown in the center and on the right in Fig. Supports/stops – pipes or wooden stakes driven into the ground. On such a “machine” you can bend up to 5-6 greenhouse arcs from a pipe up to 16x15x2 at a time. An important feature: the pipe must be passed around the stops slowly, in several steps, otherwise due to the release of voltage, a defect is possible - a reverse wave. The film on it will be wiped all the time, and it is unlikely that it will be possible to install the polycarbonate coating efficiently. The laid arcs are left in the “machine” for a day (preferably up to a week) so that the residual stresses in the metal of the pipe “resolve” (relax) and the profile of the arcs does not “spill” beyond the permissible limits.

Note: based on a bending plate, you can make a universal support-and-thrust manual machine for bending pipes and rods, see video:

Video: homemade universal bending machine

Conductor

An “earth bending slab” is essentially a bending template – a jig. Using solid conductors, pipes are bent to medium and large radii (items A and B in the figure); possibly with variable bend radius. In this case, the ends of the workpiece on the template are pulled together while the metal relaxes with a double bowstring, which is tightly twisted with a piece of rod inserted in the middle.

Bending along a jig is possible without using production space if you hang the template on the wall. Then the workpiece is fixed with a clamp and a hand winch (pos. B). Bending along an alternating radius is possible; for this, the pipe is clamped in the concavities of the profile with counter-templates. For bending pipes by tracing along the conductor, see also the story:

Video: do-it-yourself jig for cold forging from A to Z

Word and rollers and rollers

The heart of all pipe bending tools and accessories described below are profiled rollers and rollers. It is these details that primarily determine the quality of the bend. If a good-looking machine bends a 20x40x2 pipe along a radius of 2 m with a wave and/or a “propeller,” the wrong rollers are 99% to blame.

Profiles, dimensional parameters and installation relationships for rollers and rollers of pipe bending devices are shown in the figure:

Grooves and ridges in the grooves (working grooves) of rollers/rollers for profile pipes are needed to disperse process stresses in such a way as to eliminate the “bun” on the bending sides and the general “propeller”. The width of the grooves and ridges in the roller grooves for wide pipes (on the right in the figure) is within 5-10 mm. This is still not enough for a guarantee from the “propeller”, see below. Below in Fig. The device of the lever-handle for manual roller pipe benders is also shown. The rollers are secured with nuts to prevent them from falling out by the threaded shanks of the axles, but pressing the axle into the oblique groove when turning the lever greatly reduces the ability of the roller to “make a wave.” If you make grooves with a pitch of 20 mm (for reasons of strength), then, having 2-4 replaceable small rollers of different diameters, you can quickly reconfigure the tool to R IZG somewhere in the range of 20-120 mm with a step of 10 mm, which for practical purposes the goals are quite enough. Numerically expressed dimensions in Fig. are given in the table:

But what is not necessary for the rollers of a pipe bender for arcs made of corrugated pipe is “cosmic” precision - in work they are rolled to the mirror, like rails under the wheels of a train. Therefore, firstly, the rollers of a pipe bending machine for small profiles with large radii (mostly for greenhouse arcs) can be assembled from plywood disks (see figure). Then the radius of the rollers along the stream R must be at least (0.2-0.25) R IZG, otherwise the pipe may “lick” the stream, and the machine will jam, and the workpiece will be “screwed up”.

Secondly, durable steel rollers/rollers for small and large radii can be made without turning:

Video: rollers for pipe bender without lathe

and even without welding and turning:

and the rollers of a simple pipe bender for greenhouse arcs in manual broaching are made of bearings:

Roller

Manual rolling pipe benders come in 3-roller (with a pressure roller) and 2-roller (with a sliding pipe stop). Rollers here and there need to be turned according to the profile (precision is normal machine-building), therefore, of course, a 3-roller pipe bender (see figure below) will cost more, but if you do not tear the lever sharply, at the minimum R for a given pipe, the bend will give a clean defect-free bending. The working force on the lever of a 3-roller pipe bender is less than on the lever of a tool with a stop, but 3-roller bending to size is impossible - the pipe noticeably stretches behind the bypass roller, so pre-measured valuable workpieces are bent into bends and rolls by a 2-roller.

The device of a 2-roller pipe bender is shown on the left in the following. Fig., and in the center and on the right there are drawings of 2 of its options for metalwork, household and installation and repair work: tabletop and removable for installation in a vice. Please note: using a removable pipe bender with a horizontal plate is much more convenient. Therefore, many amateurs attach corners from 60x60x3 to the underside of the slab in a T-shape and clamp the device in a vice. But - only if their jaws are made of steel or gray or white tool cast iron. And now the sale is full of beautiful, chocolate-like vices made of raw cast iron. With a relatively small force, the sponges break off very well.

Note: Additionally, how to make a roller pipe bender for profile pipes without turning yourself, see the video:

Video: a simple pipe bender in 2 hours without lathe

Crossbow

A crossbow-type pipe bender is essentially a bending press, operating on the principle of pushing a workpiece between a pair of turned profiled rollers, which in this case are the press matrix. Therefore, hand-held crossbow pipe benders with a rack-and-pinion ratchet drive are rare: after the 3-4th bend of a dozen copper pipe, the hand already gets tired. Most crossbow pipe benders are equipped with a hydraulic drive with pumping by hand or an electric pump. Let’s say right away: there is no particular point in making a crossbow pipe bender yourself. The reason is not the turned rollers and/or hydraulics, but its main part: the punch (shoe). It is completely unrealistic to place the equipment necessary for its manufacture at home or in a garage and power it from a household electrical network. If you find an old worn-out shoe (and you need several of them), then instead of a more or less decent bend there will be tatters and rubble. Therefore, the purpose of this section is to help the reader choose a suitable crossbow pipe bender from those available for sale or for rent.

It can only be justified to independently manufacture a stationary crossbow pipe bender (item 1 in the figure) at the start of a micro-enterprise, respectively. profile. A set of shoes and a car jack from 10 tf for it will cost several times less than a finished piece of equipment, especially since the jack can be removed for its intended use. In such a case, the approximate dimensions of the installation frame are shown in pos. 2; its metal must withstand a breaking force of 10 tf, and a shear force of approx. up to 7 ts. But keep in mind: you can only do relatively small details. To bend the 6th pipe in the middle at 90 degrees, the entire machine will need to be raised above the floor by more than 1.7 m. Which means: a high ceiling, a strong supporting structure and a scaffold for the operator. And from the point of view of supervisory authorities, work at heights, which requires special licensing.

If you intend to buy a bending crossbow (trade name option), then it is better to buy one with a double corner frame and in a complete set (item 3): then purchasing additional shoes/rollers/rules individually will cost 2-4 times more. It is undesirable to take a tool with a straight frame (item 4), as this gives a taffy, which is noticeable in the advertising photo. The rows of roller mounting holes must be arranged with an angle of approx. at 150°, the top of which should fall on the center of curvature of the shoe at its working outlet. Then bending at 90° will be clean, and if the acceptable defects are acceptable, then the roll can also be bent.

As for the “cheap” tools with a single frame and sliding stops (item 5), this is frankly commercial hack. The bending force is hundreds of kgfs or tons, and the deviation of the bend from the plane (“whisker lifting”) due to frame misalignment can reach 3-5 mm/m, and there is a wave along the edges of the bend. This is not so scary; at first the tool bends satisfactorily. But soon the coating of the sliding jaws wears out, their metal becomes copper-plated, and there are burrs on the bend, or even a “bun” with visible cracks. In general, such a tool is for sale, but not for long-term regular work.

Dornovye

A mandrel is a bending template (conductor) to which the workpiece is not pressed, but is traced along its groove. Mandrel (bypass) pipe benders are used, firstly, if the bend of a small radius must be as clean and accurate as possible. For this purpose, the manual drive is made ratchet with reduction gear or electro-hydraulic. Manual lever mandrel pipe benders are used, secondly, if you need an inexpensive tool for quick bending of more than 90 o with satisfactory quality (staple blanks, rolls, coils).

The design and principle of operation of a manual mandrel pipe bender with a rotary jig and a gear-ratchet mechanism are shown on the left in the figure:

Roller

Rolling (broaching, roller) pipe bending machines are also known in 2 variants for a specific purpose: with a fixed and breaking table. Both, manual and machine-driven, are installed permanently or carried by vehicles for use at the place of work. They are usually used for bending profile pipes of rectangular cross-section along large radii, but round pipes can also be bent. The round timber arcs come out slightly bent with a screw (in a gentle spiral), but this defect in this case (round pipe) can be completely corrected during installation. But the “screw” of the professional pipe will definitely go with a “propeller”, which is simply invisible on a round pipe.

With fixed table

Roller pipe benders with a fixed table bend corrugated pipes over large radii without defects, exactly along the profile. Technological “tails” of the workpiece are not needed at the start and end of the process, i.e. It is possible to bend the profile to size. However, there is only one profile: a circular (single-radius) arc. In general, such bending machines are optimal for mass production of load-bearing arches of greenhouses, sheds, garages and other outbuildings, incl. at the customer's location.

The structure of a roller pipe bender is shown in the figure:

At the top left is its operating principle: the workpiece is placed on the lower rollers and pressed to the desired bending radius by the upper one, then the rollers are rotated until the “rear tail” comes out. The lower rollers are identical, this will ensure symmetrical spreading of technological stresses and, accordingly, clean, defect-free bending. The upper roller is usually made with a diameter 1.5-2.5 times larger than the lower ones; this speeds up rolling without significantly increasing the working force. When purchasing or designing a homemade pipe bender of this type, make sure that it has a bending radius scale, and that the installation grooves of the lower rollers are oblique in a “reverse herringbone” pattern (shown by green arrows). Without a radius scale, several workpieces will have to be damaged, and rollers in straight grooves, transverse or longitudinal (see below), can “shoot a wave” due to beating or displacement. During work, beware of asymmetrical installation or displacement of the rollers, then no amount of correct profiling will save them from the “propeller”. Drawings of a roller pipe bender for corrugated pipes up to 45 mm on the wide side are given in the figure:

The disadvantage of this design is that the lower rollers are installed in straight longitudinal grooves; it would be better to provide oblique ones, as shown in the inset there. The efficiency of reconfiguring the machine will not noticeably decrease, but asymmetry and adjustment failures in operation are excluded.

More about the drive

The symmetry of the drive force is also important primarily “from the propeller”. The symmetrical arrangement of the rollers in this case is not yet a completely sufficient measure.

For symmetrical spreading of process stresses, the drive roller must also be located symmetrically relative to the driven ones, i.e. The machine drive is needed on the central (upper) roller. If, for example, for ergonomic reasons, the drive is simply transferred to the lower roller (on the left in the figure), then the machine will sooner or later (or immediately) produce a “propeller” and, possibly, a wave at large radii.

In this case, both lower rollers need to be driven, synchronizing them with a rigid secondary drive, for example. chain, in the center. And it is best to make all the rollers the same and synchronize all 3. Rolling will slow down somewhat, but its fatal defects will be eliminated. If you replace the lever gate with a steering wheel, as in Fig. at the beginning of the section, and it’s heavier so that it works like a flywheel, then bending will work - “even for a rocket.”

With a breaking table

The working table of a roller pipe bender of this type consists of 2 parts: fixed and suspended on a hinge. The “hanging” part is supported by a jack, and the outgoing lower roller is installed on it. In this way, the bending radius of the pipe is precisely and smoothly set. The design is quite bulky and heavy, so it can only be installed permanently.

The distribution of technological stresses of the workpiece in a pipe bender with a breaking table is initially slightly asymmetrical. A simple measure to combat this is the only one, organizational: do not turn the drive too quickly, squeezing out productivity. But, firstly, you can bend not only to large, but also to medium radii: the adjustment limits R of the bend in a pipe bender with a breaking table are much wider. This circumstance is also significant when the table is stationary, so some master mechanics make roller pipe benders with a non-movable upper roller, and the installation of R IZG is carried out by lifting the outgoing rack and pinion mechanism, see fig.:

Secondly, having a qualified assistant, you can bend, for example, pointed semi-arches with a smoothly variable radius: one turns the drive (or adjusts the electric one), and the second pumps up the jack. Why extra beauty? True beauty is never in excess. For example, greenhouses on pointed arches are more than relevant in northern regions, where the Sun does not rise high even in summer. Note +15-20% increase in yield and 10-12% savings on lighting is already economic beauty, materially very tangible.

The structure, approximate dimensions and some design features of a roller pipe bending machine with a breaking table are shown in the figure:

Installing driven rollers sliding in longitudinal grooves is quite a valuable find. Expanding the range of adjustment of R IZG is, as they say, still seeds: by moving the lower rollers asymmetrically from the upper one, you can compensate for the asymmetry of stress spreading. In principle, after spending a lot of time and material on experiments, you can build a setting curve or table for different R IZGs, according to which the machine is adjusted for defect-free bending. True, the possibility of manufacturing semi-arches of variable radius will most likely disappear or be significantly narrowed. Which, of course, is not good.