Sheet bending technology. Bending of metals: methods and technological features. Metal bending process

Bending sounds like a simple process, but in reality, it is very complex.
  "Sheet" and "bending" are not very associated with high technology. However, in order to bend a "naughty" sheet, special knowledge and extensive experience are required. Explain to a technician who is not familiar with sheet metal that in our high-tech world, it is impossible to constantly get a 90 ° angle when bending without changing the settings. It turns out, and then - no!

Without changing the program, the angle will change if, for example, a sheet 2 mm thick is made of stainless steel or aluminum, if its length is 500 mm, 1000 mm or 2000 mm, if bending is performed along or across the fibers, if the bending line is surrounded by punched or laser-cut holes, if the sheet has a different elastic deformation, if surface hardening, due to plastic deformation, is stronger or weaker if ... if ...

WHICH FLEXIBILITY METHOD TO CHOOSE?

There are 2 main methods:
  We are talking about "air bending" or "free bending" if there is an air gap between the sheet walls of the V-shaped matrix. This is currently the most common method.
  If the sheet is pressed completely against the walls of the V-shaped matrix, we call this method “calibration”. Despite the fact that this method is quite old, it is used and should even be used in certain cases, which we will consider later.

Free bending

Provides flexibility, but has some limitations on accuracy.

Main features:

  • Traverse with the help of a punch presses the sheet to the selected depth along the Y axis into the groove of the matrix.
  • The sheet remains "in the air" and does not come into contact with the walls of the matrix.
  • This means that the bending angle is determined by the position of the Y axis, and not by the geometry of the bending tool.

The accuracy of setting the Y axis on modern presses is 0.01 mm. What bending angle corresponds to a certain position of the Y axis? It is difficult to say, because you need to find the correct position of the Y axis for each angle. The difference in the position of the Y axis can be caused by the adjustment of the lowering stroke of the beam, material properties (thickness, tensile strength, strain hardening) or the condition of the bending tool.

The table below shows the deviation of the bending angle from 90 ° for various deviations of the Y axis.

a ° / V mm   1 °   1.5 °   2 °   2.5 °   3 °   3.5 °   4 °   4,5 °   5 °
4 0,022 0,033 0,044 0,055 0,066 0,077 0,088 0,099 0,11
6 0,033 0,049 0,065 0,081 0,097 0,113 0,129 0,145 0,161
8 0,044 0,066 0,088 0,110 0,132 0,154 0,176 0,198 0,220
10 0,055 0,082 0,110 0,137 0,165 0,192 0,220 0,247 0,275
12 0,066 0,099 0,132 0,165 0,198 0,231 0,264 0,297 0,330
16 0,088 0,132 0,176 0,220 0,264 0,308 0,352 0,396 0,440
20 0,111 0,166 0,222 0,277 0,333 0,388 0,444 0,499 0,555
25 0,138 0,207 0,276 0,345 0,414 0,483 0,552 0,621 0,690
30 0,166 0,249 0,332 0,415 0,498 0,581 0,664 0,747 0,830
45 0,250 0,375 0,500 0,625 0,750 0,875 1,000 1,125 1,250
55 0,305 0,457 0,610 0,762 0,915 1,067 1,220 1,372 1,525
80 0,444 0,666 0,888 1,110 1,332 1,554 1,776 1,998 2,220
100 0,555 0,832 1,110 1,387 1,665 1,942 2,220 2,497 2,775

Advantages of free bending:

  • High flexibility: without changing the bending tools, you can get any bending angle between the opening angle of the V-shaped matrix (for example, 86 ° or 28 °) and 180 °.
  • Lower tool costs.
  • Compared with calibration, less bending effort is required.
  • You can “play” with effort: a larger opening of the matrix means less force is flexible. If you double the width of the groove, you only need half the force. This means that thicker material can be bent with more opening with the same effort.
  • Smaller investment, because you need a press with less effort.

All this, however, is theoretical. In practice, you can spend money saved on acquiring a press with less effort, allowing you to use all the advantages of air bending, on additional equipment, such as additional axles of the rear stop or manipulators.

Disadvantages of air bending:

  • Less accurate bending angles for thin material.
  • Differences in material quality affect repeat accuracy.
  • Not applicable for specific bending operations.

Tip:

  • Air bending is preferably used for sheets with a thickness of more than 1.25 mm; for sheet thicknesses of 1 mm or less, calibration is recommended.
  • The smallest bending radius should be greater than the sheet thickness. If the inner radius should be equal to the thickness of the sheet, it is recommended to use the calibration method. An inner radius less than the thickness of the sheet is permissible only on soft, easily deformable material, such as copper.
  • A large radius can be obtained by air flexible by using the stepwise movement of the back stop. If the large radius should be of high quality, only the calibration method with a special tool is recommended.

What is the effort?
  Due to the various properties of the material and the consequences of plastic deformation in the bending zone, the required force can only be determined approximately.
  We offer you 3 practical ways:

1. Table

In each catalog and on each press you can find a table showing the required force (P) in kN per 1000 mm of bending length (L) depending on:

  • sheet thickness (S) in mm
  • tensile strength (Rm) in N / mm2
  • V - the width of the disclosure of the matrix (V) in mm
  • bent sheet radius (Ri) in mm
  • minimum bent shelf height (B) in mm

Example of a similar table
The necessary effort for bending 1 meter of sheet in tons. Tensile strength 42-45 kg / mm2.
  Recommended ratio of parameters and effort

2. The formula


  1.42 is an empirical coefficient that takes into account friction between the edges of the matrix and the material being processed.
  Another formula gives similar results:

3. "Rule 8"

When bending low-carbon steel, the matrix opening width should be 8 times greater than the sheet thickness (V \u003d 8 * S), then P \u003d 8xS, where P is expressed in tons (for example: for a thickness of 2 mm, the matrix opening \\ / \u003d 2x8 \u003d 16 mm means what you need 16 tons / m)

Force and bending length
  The length of the bend is proportional to the force, i.e. the force reaches 100% only with a bend length of 100%.
  For instance:

Advice:
  If the material is rusty or not lubricated, add 10-15% to the bending force.

Sheet thickness (S)
  DIN allows a significant deviation from the nominal sheet thickness (for example, for a sheet thickness of 5 mm, the norm varies between 4.7 and 6.5 mm). Therefore, you need to calculate the force only for the real thickness that you measured, or for the maximum standard value.

Tensile Strength (Rm)
  Here, too, the tolerances are significant and can have a major impact in calculating the required bending effort.
  For instance:
  St 37-2: 340-510 N / mm2
  St 52-3: 510-680 N / mm2

Tip:
  Do not save on bending efforts! The tensile strength is proportional to the bending force and cannot be adjusted when you need it! Actual thickness and tensile strengths are important factors when choosing the right machine with the right nominal force.

V - matrix disclosure
  According to the rule of thumb, the disclosure of a V-shaped matrix should eight times exceed the sheet thickness S to S \u003d 6 mm:
  V \u003d 8xS
  For a larger sheet thickness, you must:
  V \u003d 10xS or
  V \u003d 12xS

The disclosure of the V-shaped matrix is \u200b\u200binversely proportional to the required effort:
   a larger opening means less bending force, but a larger internal radius;
   less opening means more effort but less internal radius.

Inside bending radius (Ri)
  When applying the air bending method, most of the material undergoes elastic deformation. After bending, the material returns to its original state without permanent deformation (“springback”). In a narrow area around the point of application of force, the material undergoes plastic deformation and remains in this state forever after bending. The material becomes stronger, the greater the plastic deformation. We call this "strain hardening."

The so-called "natural bending radius" depends on the thickness of the sheet and the opening of the matrix. It is always larger than the thickness of the sheet and does not depend on the radius of the punch.

To determine the natural internal radius, we can use the following formula: Ri \u003d 5 x V / 32
   In the case of V \u003d 8xS, we can say Ri \u003d Sx1.25

Soft and easily deformable metal allows a smaller internal radius. If the radius is too small, the material may be wrinkled on the inside and crack on the outside of the bend.

Tip:
  If you need a small inner radius, bend at a slow speed and across the fibers.

Minimum Shelf (B):
  To avoid flashing the shelf into the matrix groove, the following minimum shelf width must be observed:

Elastic deformation
  Part of the elastically deformed material will “spring” back after the bending force is removed. How many degrees? This is an appropriate question, because only the actually obtained bending angle is important, and not theoretically calculated. Most materials have a fairly constant elastic deformation. This means that a material of the same thickness and with the same tensile strength will spring by the same amount at the same bending angle.

Elastic deformation depends on:

  • bending angle: the smaller the bending angle, the greater the elastic deformation;
  • material thickness: the thicker the material, the less elastic deformation;
  • tensile strength: the higher the tensile strength, the greater the elastic deformation;
  • fiber directions: elastic deformation is different when bending along or across the fibers.

We demonstrate the above for the ultimate strength measured under the condition V \u003d 8xS:

All manufacturers of bending tools take into account elastic deformation when they offer tools for free bending (for example, an opening angle of 85 ° or 86 ° for free bends from 90 ° to 180 °).

Calibration

The exact - but inflexible way

With this method, the bending angle is determined by the bending force and the bending tool: the material is completely sandwiched between the punch and the walls of the V-shaped matrix. Elastic deformation is equal to zero and various properties of the material practically do not affect the bending angle.

Roughly speaking, the calibration force is 3-10 times higher than the free bending force.

Calibration Benefits:

  • accuracy of bending angles, despite the difference in thickness and material properties
  • all special forms can be completed with a metal tool
  • small internal radius
  • large outer radius
  • Z-shaped profiles
  • deep U-shaped channels
  • all special shapes can be made for thicknesses up to 2 mm using steel punches and dies made of polyurethane.
  • excellent results on press brakes without precision sufficient for free bending.

Calibration disadvantages:

  • the required bending force is 3 to 10 times greater than with free bending;
  • no flexibility: a special tool for each form;
  • frequent tool changes (except for large series).

To increase the rigidity of metal structures, various configurations of a curved sheet are used, and in particular, a bent corner. It is also used for the construction of ventilated facades and in many other areas. A bent angle is obtained from a cold sheet of metal by bending on a sheet bending equipment.

Options for making a bent corner:

The main condition for obtaining a bent corner is the absence of changes in the properties of the metal during processing. Both the first and second methods leave the metal structure unchanged at the bend points. In this case, the sheet of metal can have a thickness of up to 10 mm.

Bending sheet metal in a hydraulic press.

Sheet metal bending is a process of processing steel sheet, during which they are given the necessary shape.

The steel sheet is laid on the bending matrix of the lower table. The steel sheet can have various thicknesses up to 10 mm and lengths up to 6 meters, depending on the purpose. Under the action of the pistons of the cylinders mounted on the upper table, the punches approach the sheet metal laid on the matrices of the lower table. After the contact of the punch with the sheet metal, the pressure force begins to increase, and the punch is pressed into the metal sheet or sheet metal, deforming it first in the area of \u200b\u200belastic deformation, and then in the area of \u200b\u200bplastic deformation, which allows a certain bending of the sheet metal. All those metal layers that are located along the bend axis remain unchanged in size, therefore, all calculations are carried out precisely with reference to these metal layers.

Steel sheet bending is mainly used for the manufacture of parts of various shapes by cold bending (example: bent corner, bent channel, etc.)

Bending sheet metal on rollers.


There are many methods for bending workpieces in cold and hot conditions. Mainly used is bending of metal in the cold state on bending machines, hydraulic bending presses and three- or four-roll bending rolls.

On sheet bending rollers, sheet steel is rolled to form cylindrical, conical, spherical and saddle-shaped surfaces and ring bending (rolling). In order to avoid structural changes, the appearance of significant hardening and a complete loss of the plastic properties of steel during cold bending of billets, the residual elongation should not go beyond the yield strength. In the manufacture of bent profiles on press brakes, the internal radii of curvature for structures made of carbon steel that absorb static load must be at least 1.2 sheet thicknesses, and for structures that accept dynamic loads, at least 2.5 sheet thicknesses. For sheet parts made of low alloy steels, the minimum values \u200b\u200bof the internal radii of curvature should be 50% greater than for carbon steel.


Plate bending rollers have three or four horizontal rolls on which sheet steel is bent, the maximum width of which is 2100-8000 mm and the maximum thickness is 20-50 mm. The most common are three-roll rollers with a pyramidal arrangement of rollers. Two lower drive rolls rotate in the same direction. The upper roll moves in height and rotates as a result of friction between the rolls and the bending sheet. One bearing of the upper roll can be folded to the side so that a bent part can be removed. Before flexible sheet metal parts of a cylindrical shape, both ends of the sheet are folded onto the backing sheet. The backing sheet should have a width 2 times the distance between the axes of the lower rolls, and the bending radius should be less than 10-17% of the bending radius of the part, taking into account the elastic deformation of the steel. The thickness of the backing sheet is usually taken 25-30 mm, however, it should be at least 2 times the thickness of the rolled sheet, and the thickness of the rollers should be sufficient to bend the sheet 3 times more than the rolled sheet. After bending, the backing sheet is removed and proceed to rolling, for which the sheets are passed through the rollers several times in both directions. The degree of bending of the sheet is controlled by raising or lowering the upper roll.

Both methods allow bending of sheets up to 6 meters, the metal can be both black and stainless. The big advantage of the bent corner can be considered the possibility of manufacturing with a variety of shelf sizes. The corner can be symmetrical, but it is possible to produce a multi-gender with given parameters.

Metal bending is a technological operation in which the product takes the required dimensions and shape by compressing the inner and stretching the outer layers of the material. As a result, a bulk product is obtained from a blank of a flat shape without welded and other seams and joints.

Bending sounds like a simple process, but in reality, it is very complex. The value of bending is also difficult to overestimate in the modern post-industrial world. No matter where you look, bent sheet metal structures are everywhere. Even press brake manufacturers are amazed at how sophisticated parts are made on the equipment they have developed.

All this became possible thanks to the active introduction of CNC, the use of several controlled axes in the bending technology, the latest hydraulic systems and measuring electronics, as well as the widespread use of robots. The main engine for the accelerated development of high-precision bending technology was the ubiquitous transition of the metal industry to the use of high-performance die-cutting presses and sheet metal.

Historically, this technological operation arose almost simultaneously with casting and forging - the primary stages of metalworking. Having learned how to bend metal billets correctly, people solved a huge number of urgent domestic and military tasks, starting from creating complex tools for hunting and agriculture, and ending with the production of weapons.

Sheet and Bending   not very associated with high technology - high tech, however, in order to bend the "naughty" sheet of metal, special knowledge and vast practical experience are needed. Explain to a technician who is not familiar with sheet metal that in our high-tech world it is impossible to constantly get a 90 degree angle while bending without changing the settings.

Without changing the program, the angle will change if, for example, a 2 mm thick sheet is made of stainless steel or aluminum, if its length is 500 mm, 1000 mm or 2000 mm, if bending is performed along or across the material fibers, if the bending line is surrounded by punched or holes cut by the laser, if the sheet has a different elastic deformation (hot rolled), if the surface hardening during the deformation itself is stronger or weaker, etc. etc.

Yes, we can talk a lot about sheet metal bending as a professional metalworking industry, but perhaps the most important thing to note.

1. Sheet metal bending- It is a high-performance, fast and high-precision operation.

2. Replacing welding with a flexible one, as a rule, is very beneficial when increasing the speed of the production process and while providing additional strength of the product due to the so-called stiffeners.

3. Metal bending is rarely the primary operation, as a rule, its task is to bring the part as close as possible to the final form (presentation).

4. Bending of complex multi-profile products from sheet metal (including flattening and making loops) is very dependent on the use of rare special tools - narrow, curved punches and forging tooling.

5. Bending of blanks from a thick (more than 5 mm) sheet strongly depends on the “tonnage” of the machine, ie from a characteristic such as beam force, measured in tons per meter.

6. The bending of small sides (bends) is directly linked to the physical characteristics of the metal - its thickness, stiffness and fluidity. So, for example, it is technologically impossible to get a board 2 mm high from a sheet 1 mm thick flexible, it is necessary to apply the stamping operation.

7. Also, in a standard cold way, bending a metal workpiece with a thickness of more than 5 mm with an internal bending radius less than the thickness of the metal itself is fraught with rupture of the outer plane of the part.

Bending sheet metal in our company is carried out on a 120-ton, 3-meter hydraulic press with CNC manufactured by Baycal. The bending machine used in our production has a wide arsenal of equipment (dies and punches) that allow us to fulfill even the most complex orders.

The price of bending metal

Bending length, m

Number of bends

from 11 to 100

from 101 to 1000

from 1000 to 10000

These prices are valid only for ferrous steels up to and including 2 mm thick.

Bending metal 3 mm   - coefficient 1.2

It is flexible metal 4-6 mm   - coefficient 1.3

It is flexible metal 7-10 mm   - coefficient 1.5

Bending stainless steel products, prices are set separately, based on the volume of the order.

Such a technological operation as sheet metal bending allows, with minimal physical effort, to form a workpiece of the required configuration.

An alternative to bending metal is the welding process, but in this case it takes much more time, and financially it costs a bit more.

Bending of sheet metal can be done manually or automatically, however, in both cases the technology of the process itself remains unchanged.

In the case when the rolling is flexible, which has a large radius, as a rule, the neutral layer is located in the middle part of the thickness.

In turn, if the minimum radius is taken, then the aforementioned layer is already shifted directly towards the compression region of the material.

In industrial production, the technology of sheet metal bending is carried out using special equipment, while preliminary calculation is performed and the corresponding GOST is taken into account.

The do-it-yourself rolling bending technology has its own characteristics, despite the fact that the necessary calculation must also be made and GOST taken into account.

In this case, a special device is used, and in order to change the configuration of the metal sheet, it is necessary to make certain efforts and be sure to take into account the calculation.

To change the shape of the rolled metal, you can use several different methods.

Welding is very often used in this case, but such a thermal effect on the metal not only greatly affects its structure, but also significantly reduces its strength and, consequently, reduces its service life.

In this case, it is possible to change the shape of the sheet metal due to a certain effort at which no structural changes occur in the workpiece.

The peculiarities of metal rolling are that in performing this metalwork operation, the outer layers of the material are stretched and, accordingly, the inner ones are compressed.

The technology of bending any sheet metal consists in the fact that part of the hire is bent in relation to another at a strictly defined angle.

The calculation allows you to get the value of the specified angle of inflection.

Of course, due to the applied force, the metal itself undergoes a certain deformation, which has an acceptable limit, which according to GOST depends on such parameters as the thickness of the material, the value of the bending angle, as well as the fragility and speed of the operation.

This technological operation is carried out on special equipment, which makes it possible to obtain the product as a result without any defects.

In conditions when the work is done with your own hands, a special device is used for bending metal.

In both cases, it is imperative to take into account the fact that if the product is bent with irregularities, microcracks will form on the surface of the material, which will subsequently cause the weakening of the metal directly at the bend, which can lead to serious consequences.

Modern capabilities allow bending of rolled products of various thicknesses, while the generated stress must exceed such a parameter as the elastic limit.

In any case, the deformation of the sheet metal should be plastic in nature.

It should be noted that the seamless design obtained in this way will have high strength and have a certain resistance to corrosion.

Types and types of bending

Any bending of metal can be done both with your own hands and with the use of special professional equipment designed for these purposes.

It should be noted that when performing this technological operation with your own hands, you will have to spend certain physical efforts and time.

In this case, bending is carried out using pliers and a hammer, in some individual cases a special device is used.

It should be noted that do-it-yourself bending of a thin metal sheet, as well as aluminum, is carried out using a mallet.

At industrial enterprises, they try to automate this process in every possible way and use directly manual or hydraulic rollers for bending, as well as special roller assemblies.

For example, to give the product a cylindrical shape, the bending of the metal is carried out using rollers. Thus, pipes, chimneys, gutters and much more are obtained.

Most often at industrial enterprises, metal bending is performed on special press brake.

Depending on the functionality of such presses can have a different device and, accordingly, sizes.

It should be noted that modern equipment allows you to perform high-tech operations with metal.

So, new industrial machines make it possible for one working cycle to simultaneously bend the sheet along several lines, which makes it possible to produce parts of any complexity.

As a rule, such equipment is quite easy to operate.

You can reconfigure it to work with other material quickly enough.

This operation requires special attention, if necessary, to bend sheet aluminum.

This is due, first of all, to the fact that in sheet aluminum, the parameters of strength and elasticity have slightly different values \u200b\u200bfrom other types of metals.

Self bending

Each metal has its own GOST, which must be taken into account when calculating, in which the minimum bending radius of the sheet is obtained.

The calculation, in which the parameters are indicated, is always individual. Features of bending a metal sheet take into account not only the minimum bending radius, but also the coefficient of elasticity, as well as strength characteristics.

Bending a metal sheet allows you to get profiles with different configurations, prefabricated partitions, slopes, as well as many other products.

Before proceeding to bending metal, it is necessary to make an appropriate calculation in accordance with GOST and determine the minimum radius of the bending line.

It is also necessary to determine the length of the bending strip, and it is necessary to make a minimum allowance directly on each bend line.

The sheet metal itself from aluminum, stainless steel, etc., should, if necessary, be aligned and cut in accordance with the drawing. Do-it-yourself cutting is usually carried out with scissors using appropriate technology. if you don’t make an effort, then nothing will work.

The metal workpiece is firmly clamped in a vise of suitable dimensions along the drawn bending line, after which the first bend is made using a heavy hammer.

After this, the legs of the bracket are marked and in a vise, with the help of a hammer, both legs are unbent in a given direction.

At the end of the work using a square, you must make sure that the workpiece meets all the specified parameters.

If there are some discrepancies with preliminary calculations, then they should be corrected in the same sequence.

More details on how do-it-yourself bending of metal sheets with a vise and a hammer are described in the video, which is posted below.

Metal cutting procedure

As a rule, before bending metal blanks, they are given the shape specified by the drawing, which makes it possible to simplify the work and obtain a more accurate bend radius.

Cutting a metal sheet is a separate technical operation, which is carried out according to its technology.

In most cases, the cutting of metal blanks is carried out using sheet shears, which are called the guillotine.

Such machines, as a rule, are installed at enterprises and allow you to quickly perform the necessary work, taking into account the bending radius and density of the material.

At home, metal cutting is carried out using special locksmith scissors.

It is worth noting that manual scissors perform metal cutting with a minimum thickness.

For thicker metal, chair or roofing scissors should be used.

If necessary, metal cutting at home can also be done with a hacksaw.

In this case, you will have to spend some physical effort and monitor the quality of the resulting slice.

If metal cutting is carried out with a hacksaw, then when performing work, the tension of the blade should be controlled, since the evenness of the cut largely depends on this.

How to cut a metal sheet with your own hands is described in the video below.

In the process of large-scale construction, the question often arises of how to bend sheet metal or metal elements, such as pipes. In order to bend pipes of small diameter, a vice is often used. Pipes having a large diameter are bent on specially designed machines. They are also used if during construction it became necessary to bend sheet metal.

During construction, sometimes it becomes necessary to bend a sheet of metal, for example, to make pipes or a roof ridge.

When bending sheet metal using a bending machine, the use of welding is not required, which guarantees the absolute preservation of the structure of the material. The metal sheet is necessarily bent taking into account its thickness and ductility, having previously determined the radius of bending.

A little bit about sheet metal bending technology

Homemade bending machine consists of:

It is possible to bend sheet metal by securing it in a vice, and using a simple device from two corners and a lever handle.

  1. Beds.
  2. Flywheel nuts.
  3. Sheet for bending.
  4. Clamp.
  5. Clamps.
  6. Punch for crimping.

In order to bend sheet metal into the shape you need, you need to perform certain actions. The advantage of the bending machine is the ability to keep the metal intact, unlike, for example, welding joints, due to which the life and strength of the material are significantly reduced.

In the process of metal bending, the outer layers are stretched and the inner ones are compressed. The result of using a bending machine is a bent part of a sheet metal or metal element at a conceived angle.

As you know, when bent, the metal is deformed. Its degree will depend on what thickness the material with which you have to work has. A significant role here is played by the angle of the curved part and the speed with which you will bend the metal. In this case, it is worth taking into account the degree of plasticity of the material.

In order to bend sheet metal, special equipment is required with which you can avoid any damage to the material. If you decide to cope with this task yourself, it is worth considering the fact that incorrect actions can lead to various defects. Incorrect sheet metal bending technology can harm the entire finished structure. Using a bending machine, it is possible to bend a sheet having any thickness.

Name of parts of the bending machine.

When bending sheet metal, the stress should exceed its maximum elasticity. Using a bending machine, it is possible to achieve plastic deformation of the sheet. The shape of the finished structure will not change.

Bending sheet metal using a special bending machine has a number of undeniable advantages, among which the following can be noted:

  • high strength of the finished structure;
  • the opportunity to get a solid design;
  • the elimination of corrosion in the bend area;
  • the ability to get the angle you need seamlessly.

Bending sheet metal using a machine also has its drawbacks:

  • high cost of equipment;
  • do-it-yourself work is a laborious process.

Despite the presence of some disadvantages, sheet metal bent using a machine is distinguished by its high quality. Unlike the design with a welded seam, it is not “afraid” of rust.

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Sheet Metal Bending Technology

The scheme and name of the details of the bending machine in the context.

Metal bending is done manually, while using equipment. This work requires the use of force. In this case, you will need pliers and a hammer. In order to bend sheet metal having a small thickness, you can use a mallet.

In order to bend a metal sheet, the following materials and tools are needed:

  • sheet metal;
  • rollers;
  • press (or roller machines);
  • mechanical hydraulic rollers (necessary if sheet metal needs to be shaped like a cylinder).

Using hydraulic or electric drive rollers, pipes can be made. Often bending is needed during home construction, when gutters, metal frames, profiles, pipes, etc. are made. By bending sheet metal with your own hands, you have the opportunity to make a pipe of the diameter you need. Using machines, it is easy to give a conceived shape to a material having a galvanized coating.

If you cannot afford the purchase of a special bending machine, and construction work often requires bending, using the instructions, you can make the equipment yourself. The machine is performed using a pre-prepared template made of wood. Moreover, it must be made in a curved shape.

Manual bending is performed in a vice with a hammer.

When determining the fold of a future product, you should consider its size. The length that the future design will have is calculated according to the radius of the sheet bend. When making blanks, for rectangular bends (if rounding is not required), allowances for bending are left, which are 0.5 of the thickness of the material.

It is most convenient to work independently with plastic metals such as brass, aluminum and copper. As for the possible radius of the curved part, it will completely depend on how the bending was performed, as well as on the quality of the metal itself. For products with a small rounding radius, plastic materials are required.

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How to bend metal with your own hands: making brackets

In order to make a bracket with your own hands, you will need:

  1. First of all, using the scheme, the length of the strip that the workpiece will have is calculated, then, it is necessary to calculate the bending of the sheet. When performing the calculation, it should be remembered that for each bend it is necessary to leave a margin of 0.5 thickness and 1 mm bend of the ends.
  2. According to the scheme, you should cut the workpiece, then mark the areas for future bending on it. In order to make a bend, squares and a vise are used.
  3. The workpiece should be fixed in a vice approximately to the level of bending. Using a hammer, you can begin to perform the first bend.
  4. Next, rearranging the prepared element, clamp in a vice and perform the following bend.
  5. Your next step will be to determine the marks for the length of the legs of the future bracket. In order to bend the bracket with a bar rim, a vise is also used. To do this, bend two of its legs at once.

If you need to clarify the bend, you can apply a triangle. In case of improper bending, you can correct errors by using a hammer and a bar of the frame.   Having achieved the desired bend, saw off the excess material, so as to obtain the desired dimensions.

 

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