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Basic Knowledge Of Profile Bending Machine

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Profile Bending Machine

What Is Profile Bending Machine?

Profile bending machine(aka section bending machines, and angle roll) is equipment for the radial forming of metal profiles. It works similarly to a plate rolling machine. However, its design is much more complex. It is equipment that cold-bending metal profiles according to the principle of the three-point circle. Profile benders can curve a wide variety of metal profiles (such as carbon steel, stainless steel, aluminum, copper, etc.) into round, arc, spiral, and other workpieces.
Working Principle: The working principle of the profile bending machine is roll bending, it is a process whereby obtains cold process deformation with a wider bend radius that theoretically can range from 5 times the cross-section to infinity. The metal profile is made to pass through a set of three rollers that, after one or more passages (depending on the difficulty of bending), will form an arch with the required radius of curvature. Roll-bending is, generally speaking, a simpler process than bending.
Metal Profile: A profile is the constant cross-sectional shape of a straight length of material. The profiles or “sections” as they are often called, can be elementary shapes or very unique custom-designed extrusions. Not only can the profiles vary in complexity, but so can the curved design of the overall product.
What is profile bending? Metal profile bending refers to the production of curved lengths of steel, aluminum, brass, and other various metals with specific profile shapes.

Double-pinch profile bending machine

bending process of 3-roll section bending machine
bending process of 3-roll profile bending machine

PBH and PBA series double-pinch profile bending machines that come in 3-roll or 4-roll. The Double-Pinch Bending Machine with High-Precision, High Productivity, and Long-Term Reliability.

The advantages of double-pinch machines

angle roll
3-roll profile bending machine

3-roll double-pinch angle rolls are economical profile bending machines that are relatively easy to operate. The side rolls are positioned to the right and left of the top roll and are on the same axis.

The axis of each roll helps make the bend. The “back” side roll (at the far side of the feeding point) also functions as a back gauge to square the plate for proper alignment. This eliminates the need for someone to assist the operator. Three-roll, double-pinch section bending machines do not require the operator to remove, flip, and then try to square the plate a second time after pre-bending, as is the case with three-roll, initial-pinch machines.

bending process of four-roll section bending machine
bending process of 4-roll profile bending machine
angle roll
4-roll profile bending machine

The 4-rollers machine has one more pressure roller than the 3-rollers machine, which can clamp the profile more under the upper roller and improve the bending accuracy, but it will make the operator’s operation more cumbersome while reducing the bending ability of the same model.

Whilst four rollers CNC profile bending machines produce fast, accurate bends, three roll machines are ideal for fabricators working with a wide range of material types.

Working principle

The double-pinch profile bending machine has two bending modes: symmetrical bending, and asymmetrical bending.

The relative position change of the workpiece (through the up and down movement of the upper roller shaft or the lower and upper roller shaft) and the pressure generated during the rotation movement in the direction perpendicular to the deformation of the profile itself cause the profile to produce continuous plastic deformation (make the outer layer of the profile Deformation) The fiber stretches, the inner fiber shrinks to produce bending deformation, the middle fiber does not change), and the workpiece with a predetermined shape is obtained at room temperature (we call it cold bending).

Symmetrical bending of profile bending machine
Symmetrical bending

Symmetrical bending

Refers to the three rollers in a symmetrical shape (pyramid shape) during bending. The upper roller or the two lower rollers rotate in a symmetrical relative position at the center to apply pressure to the profile to produce plastic deformation
Disadvantages: It is not possible to pre-bend the profile. There are larger straight edges at the end of the workpiece after bending, which causes waste.

 asymmetrical bending of profile bending machine
asymmetrical bending

Asymmetrical bending

Refers to the asymmetrical shape of the three rollers during bending. The upper roller and the two lower rollers move vertically at asymmetrical central positions, and the upper roller or the two lower rollers rotate to exert pressure on the profile. Produce plastic deformation. The end of the profile can be pre-bent.