Bending machines, also known as “bending machines,” are used to bend tubes, bars, profiles without bending to obtain angles, “T” profiles, “U” profiles, and so on. This machine is typically used in the metalworking field. Rollers are the most important part of the machine. They apply a combination of forces to the profile, the result of which determines the deformation perpendicular to the length of the part.
How to choose a bender?
To be able to choose the right bender for your application, you must first define whether to use it for tubes, bars, or profiles.
Next, you need to have an idea of the dimensions of the section to bend, for example, the diameter of the tube and its wall thickness, or the height and width of the bar. These factors allow you to determine the size of the bending rollers, also known as “rollers”, their spacing, and therefore the size of the bending machine required.
You also need to know the minimum bend radius and bend angle to achieve. As a general rule, it should be taken into account that for tubes, the minimum bend radius is 2.5 times the outer diameter of the tube, and for bars, the minimum bend radius is 3 times its cross section. You need to know the bending angle you want to achieve so that you can select the bender settings. For example, if you choose a roller bender, it will take several cycles to get a bending angle above 90 °.
Of course, you also need to know the properties of the bending material, such as tensile strength and elongation.
Do you know what the difference between cold bending and hot bending is?
Bending machines are designed for cold bending, but there are also bending jigs, especially used in steel mills and boiler manufacturing workshops, where hot bending of bars, tubes and sections is possible. There is also another technique for performing hot bending. Inductive bending can, for example, bend large stainless steel pipes.
Unlike hot bending, cold bending maintains the mechanical properties of the metal. Hot bending, on the other hand, is more flexible in deformation and can produce narrower bend radii than, for example, cold bending.
In which case would you choose a manual bender?
If you use it only occasionally, if you need low volume production, or if you don’t need high accuracy, you can check the manual bender. For manual benders, bending accuracy and operational reproducibility depend on the operator’s know-how. On the other hand, the investment is minimal compared to industrial 1inch 25mm rebar bender.
The manual bender can be mechanical or hydraulic.
Mechanical hand benders are typically used for small diameter tubes. They have cranks that drive bending rolls those themselves drive tubes, bars, or sections. Hydraulic hand tube benders are used to bend larger diameter tubes. They are equipped with cylinders that allow regular thrust to be applied to the bending rolls.
How to choose an automated pipe bender?
To choose the right type of automatic pipe bender, you need to define your needs in terms of speed, performance, and accuracy of operation. Automatic hydraulic benders offer a high level of accuracy and high quality bending, but are relatively slow, especially when compared to electrical benders.
Electric benders are fast
CNC benders are programmable machines that offer very good reproducibility and high accuracy, but they mean a lot of investment.
How to choose the number of rolls?
Bending machines are usually equipped with three bending rollers. Depending on the model, two of the three rollers can be electric, or all three can be electric. There are also 4-roller benders that can be used for specific tasks.
Electric 2-roll benders are more economical. These are rather used for smaller series, as they tend to be marked by striped or grooved rollers if the finishing of the parts is not the predominant standard. The electric 3-roller bender is faster and offers a better level of finish, but at a higher cost than the electric 2-roller model. With a 4-roll bender, you can easily bend both large and small diameter tubes. These benders are more efficient.
Rollers and drive systems affect the finish quality and durability of the machine. The rollers are hardened and polished over time to ensure good resistance. The drive system is also designed to withstand heavy loads. If the drive system is a gear system, induction hardening sprockets are the strongest. If the drive is due to a universal joint, the system can be equipped with plastic parts intended to be damaged during excessive effort, which facilitates maintenance.
What are the other criteria for choosing a bender?
Benders can be pyramidal or asymmetric. In the Pyramid Bender, only the top center roll moves. The distance between the two lower rollers is fixed. On the other hand, it is superior to that found in asymmetric benders, allowing you to bend large diameter tubes while gaining a larger bending radius. In asymmetric benders, the central roller is fixed and the lower roller, which moves in an arc, makes the adjustment. This principle allows you to perform a variety of tasks with small deformations and minimal bend radii.
The metal bender can be vertical or horizontal depending on the working environment. Vertical benders require a minimal work surface. On the other hand, the height of the workplace should be sufficient for the work to be done. Horizontal benders require a large work surface and may need to provide guides to support bending parts. Some benders come with a mouse. This is an articulated mandrel that takes the internal shape of the bendable profile and prevents the outer part of the bendable profile from being hollowed out.