The CNC press brake knows from the bending process that after bending the workpiece, the edges of the decorative surface are all arc-shaped, and the radius is proportional to the thickness of the metal sheet. The thicker the sheet, the larger the radius of the arc formed by bending.
In the elevator assembly, if the bending radius is large, the wall panels and ceiling bending panels will have large splicing gaps, which will affect the appearance.
In this regard, in some elevators with special assembly requirements, we generally first grooving the plates before bending. After grooving the metal sheet, the remaining thickness of the sheet will greatly reduce, so that the bending radius of the workpiece can greatly reduce, and the assembly gap will also be well controlled.
Since the remaining plate thickness at the bend after grooving is thinner, the deformation force during bending will accordingly reduce, and will not spread so as to affect the unbend area, so the bending phenomenon of the surface of the workpiece after bending will also reduce.
In addition to the above advantages, the grooving bending process also has the characteristics of reducing the required tonnage of the press brake machines, bending complex workpieces, and better controlling.
In addition, the grooving process also needs to pay attention to the following points
Setting of grooving depth
The thickness of the metal sheet is different, and the depth of the groove is also different. In the elevator grooving and bending process, the thickness of the remaining sheet after grooving is generally 40% to 50% of the original sheet.
Such as if the plate thickness is 1.0mm, the grooving depth is 0.5mm, and the thickness of the remaining material is 0.5mm; if the plate thickness is 1.2mm, the grooving depth is 0.7mm and the thickness of the remaining material is 0.5mm;
The thickness of the plate is 1.5mm, then The depth of the planing groove is 0.9mm and the thickness of the remaining material is 0.6mm; the thickness of the board is 2.0mm, the depth of the planing groove is 1.2mm, and the thickness of the remaining material is 0.8mm.
Too shallow gouging will make the bending effect insignificant, and too deep will easily affect the structural strength of the workpiece.
V groove angle setting
After the metal sheet undergoes the grooving process, although the bending springback is greatly reduce, it still exists. Therefore, when planning the V-shaped groove , the groove can flexibly groove according to the bending angle of the workpiece.
Generally, the grooving angle of the V-groove of stainless steel sheet is 1°～2° larger than the bending forming angle. For example, for a workpiece with a forming angle of 90°, the V-groove grooving angle is generally 92°. In this way, the angle error caused by the bending springback can be well avoided.
Types and selection of slot knives
The types of groove knives are mainly divided into diamond top corner groove knives, square groove knives, triangular groove knives, circular groove knives, etc. When grooving, you can choose suitable tools according to the different shapes and angles of V grooves. When planing ordinary V grooves, the angle of the tool should be smaller than that of the V groove.
For example, when the V-slot angle is 45°～60°, you should choose a groove knife with a rhombus apex angle of 35°; when the angle is 60°～80°, you should choose a regular triangle groove knife; when the angle is 80°～90°, The slot knife with a rhombus top angle of 80° should be selected; when the angle is greater than 90°, a square slot knife should be selected; when a round slot is made, a round slot knife should be used.