Brake (sheet metal bending)

Flap bending is a manufacturing process and classified in metal forming. By pivoting bending can produce similar profiles such as by flanging.

Bending sequence during pivoting bending

Although differ greatly Folding Machines in speed, flexibility and thickness, they still turn all the same way:

• The stop - and high retention system positions the sheet of steel or other metal materials
• The upper beam clamps the sheet against the lower beam
• The bending beam bending the sheet to a desired angle.

The bending beam can be moved by hand or by motor power. For clamping the plates by means of the upper cheek serve spindle, eccentric or hydraulic cylinder. The tools of the upper beam, the bending beam and the lower beam are exchanged to adapt the machine to different lengths and bending part bent part geometries.

Flap bending is particularly suitable for bending of flat plates which are to be formed in the edge region. When bending the flat sheet remains lying on the support system in the machine. The operator must not hold the weight of the sheet outside the machine, yet he has the high lead sheet during bending and support the weight plate after bending. A single operator can thus handle even large and heavy plates alone.

Large parts of loads, turns and unloads the operator of the rear of the machine and uses a one-sided extended backgauge. He edited Small parts of the front of the machine.

The principle of the swivel bending is also used in fully automatic bending centers.

Sheet thickness, bend radius

Modern Folding machines automatically arise when the program starts to be processed on a sheet thickness and the desired bend radius. For thin sheet metal machines ( up to 2 mm ) usually only the height of the bending beam is adjusted to the pivot point, causing the machine adjusts to the sheet thickness. Above 2 mm adjustment of the bending beam and the lower beam ( displacement of the radius -to-center ) is essential to achieve accurate bending results and to avoid cracking or breakage.

Advantages of the swivel bending

• Very short legs can be bent
• By the juxtaposition of short segments can be bent any radius ( Step bending)
• Open and closed to size envelopes can be bent
• Perforated sheets can be accurately bent, because the sheet is clamped in the bending
• It can be bent with a sensitive surface sheets, as there is little relative movement between the tool and the sheet surface (stainless steel, coated sheet )
• Low tool wear, due to the low Realtivbewegung
• For different bending angle, bending radius, sheet thickness and leg length is usually only a single universal set of tools necessary
• No additional angular displacement measuring instruments necessary

Adapt

Automatic tool clamping systems clamp the tools the top and bending beam when the operator starts working. Along with a graphical setup instruction reduces itself a comprehensive tool change from two to five minutes. When swivel bending dividing the working length often split into several stations on to finish completely bent parts with a single tool design can.

Programming

Modern CNC controls are easy to use. The operator draws the bent part with your finger on the screen. The user simply paint a flange to the desired level and the desired angle. The controller automatically determines an appropriate bending sequence, shows the development of the required sheet ( cut length ) and compensates for springback in bending. On the screen, the operator can see the finished bent part, each bending step and the bending program generated.

However, the software needs to process in accordance with the material selected, and the nature of the bending beam to be adjusted precisely to create true transactions of the part to the punching or laser fabrication. See more in the article to the bending shortening.

Accuracy

Accuracy of the bending angle

When bending machines the bending beam pivots with an accuracy of 0.1 degrees and thus ensures accurate and repeatable bending parts.

Accuracy of the bending leg

When swivel bending the whole part and not the individual bending leg is struck. To follow all the inaccuracies of the blank in the first leg disappear each bending direction. All the other leg and in particular the length and the width of the part are dimensionally exact.

Tolerances in the sheet thickness

Tolerances in the sheet thickness does not influence the bending result, since the bending beam as the reference always engages the outer side of the sheet.

Straightness of the bend

The rigidity of the machine determines crucial as just the bends. Thin sheet metal machines come thanks to a deep bending beam without crowning. For large thicknesses, the use of Bombiersystemen is common. They compensate for the deflection of the bending beam by increasing the center of the bending beam. In principle can be made between static and dynamic camber to unterscheiden.Bei a static camber is once set curvature of the upper - lower or bending cheek over the entire process, regardless of the section to be bent angle gleich.Da but the resilience force not only on the material thickness, the strength of the material, the rolling direction is so dependent, but substantially also by the angle to be bent, the bending curvature of the rail during the bending process in correlation with the angle corresponding to ändern.Dies is having a dynamic crown possible. While in the manual version, the crown is usually adjusted by a dial done this process is vollautomatisch.Hierbei when using a hydraulic- dynamic camber without manual rework of the main factors, sheet thickness and springback, a correlation coefficient derived whose instances to the each to be bent plates the corresponding crown is derived. The collection of the required data is done with the orthogonal factor analysis after varimax method.

Areas of application

• Metal doors / Furniture / Shelves
• Transport facilities
• Advertising signs
• Electrical and electronic housing
• Air conditioning and boiler linings / Ovens
• Machines and machine covers
• Roofing and façade sheets / metal components
• Luminaire body
• Restaurant and Kitchen equipment
• Cleaning machines
• Medical devices and equipment
• Vending Machines
• Partitions
• Elevators and escalators