Bending process and driving mode of profile bending machine

Section bending machine (Also called profile bending machine or section bender) is Is a down-adjusting or up-adjusting bending machine.

Drive of profile bending machines

Three-axis structure

The machine has three shafts. The upper shaft of some models is the driving shaft, and the other two shafts are the driven shafts. All three axes of models with higher configuration are drive axes. A special mold for section bending of the profile is installed at the end of the shaft.

Principle of Bending

Through the up and down movement of the upper shaft or the upper and lower shafts, and the pressure generated in the direction perpendicular to the deformation of the profile itself during the rotational movement, the profile produces continuous plastic deformation (deforms the outer layer of the contour), and the fiber stretches, and the inner fiber shrinks Bending deformation occurs, the intermediate fiber does not change, and a workpiece with a predetermined shape is obtained at room temperature.

Further reading:What is profile bending machine?

Drive way

There are three driving methods, and only two common ones are introduced here:


hydraulic motor of profile bending machine
hydraulic motor of profile bending machine

The standard motor is directly coupled to the drive shaft through a gear box, and it can also have a transmission system. The price of this motor is moderate, but the accuracy is not high (although it is still high enough in most cases). Bending efficiency is usually very high, but obviously the overall efficiency also depends on the transmission system used. The inverter can be used to achieve continuous speed adjustment, which is usually used in low-end models.


The hydraulic motor is directly connected to the roller shaft through a gear box. Speed ​​adjustment can be easily achieved by using a proportional valve that adjusts the oil flow.

Commonly used up and down movement adjustment of bending shaft

Screw adjustment

In some small profile bending machines, its upper shaft can move up and down, so it is equipped with a set of screws for up and down adjustment to provide pressure. Advantages: economical; disadvantages: slow speed and low accuracy.

Hydraulic adjustment

The rollers of the machine are connected to hydraulic components. The cylinder is connected to the hydraulic unit and is hydraulically driven. This system is the most commonly used system because it can provide high load capacity and always maintain a reasonable low cost. The positioning accuracy is sufficient to meet the needs of most applications.

Bending process of the section bending machine:

Improtant before the profile bending use the section bender.

1.Metal profiles is placed between the upper and lower rollers of the section bending machine.

2.A lower roller of the machine rises and clamps the profile together with the upper roller (the screw-adjusted model uses the upper roller to descend and clamps the profile together with the lower roller). One guide roller supports the profile to ensure that the profile remains in the correct position. Horizontal position to obtain high-precision bending.

feed proffile
Put the profile between the upper roller and the lower roller

3.The right roller rises slowly, begins to roll, and pre-bends between the main roller and the left roller

Pre-bending on the right side of the profile
The right roller slowly rises and begins to roll, pre-bending between the main roller and the left roller.

4.The left roller is down, while the right roller is up, sending the profile to the left, and the three rollers start to roll. Pre-bending between the main roller and the right roller

Bend end
Bend end

5.End of pre-bending and rolling