What is Metal Bending?

Bending is one of the most common sheet metal fabrication operations. Also known as press braking, flanging, die bending, folding and edging. using forces to change the shape of a sheet. This is done to achieve the desired form or shape needed for a manufacturing process. The external force only affects the sheet's outward features. The sheet metal's malleability allows it to be shaped in a variety of ways.

Bending methods

Sheet metal bending methods aim to shape sheet metal structures. Each has their own advantages. The most common sheet metal bending methods are:

V-bending

V-bending is the most commonly used sheet bending method as it is applied to the majority of bending projects. It uses a punch and v-die to bend sheet metals at specific angles. The bending punch presses on the sheet metal put over the V-die during the procedure. The angle generated by the sheet metal is determined by the punch's pressure point. This makes this process simple and efficient because it can be used to bend steel plates without changing their position.

Bottoming

Bottoming is also known as pressing or striking the bottom. As suggested by the term "bottom pressing," the punch presses the metal sheet into the surface of the die, so the angle of the die determines the final angle of the workpiece.

In bottoming, the bend is influenced by the position and form of the die angle. Similarly, the compressed sheet metal cannot spring back. Due to the power of the punch and the angle of the die, the sheet metal is formed into a permanent structure.

Coining

Coining is a widely used bending process due to its precision and distinctive ability to form distinguishable sheets. There is no spring-back of the sheets during the procedure. This is because the coin penetrates the sheet metal at a limited radius, leaving a dent that can be used to differentiate across sheets.

Air Bending

Coining is a bending procedure used for its precision and the capacity to produce customized sheets. There's no sheet springback. The coin penetrates the sheet metal at a limited radius, causing a dent to differentiate sheets.

Air bending is less precise than bottoming and coining. It's used for its simplicity and tool-free manipulation.

There is also a drawback. Air bending is the only method prone to the spring-back of the sheet metal.

Roll Bending

Roll bending is the process of bending sheet metal into rolls or curved shapes. To make different bends or a large round bend, a hydraulic press, a press brake, and three sets of rollers are used. It is useful for creating cones, tubes, and hollow shapes because it uses the space between its rollers to make bends and curves.

U-Bending
U-bending is in principle very similar to V-bending. It uses the same instrument (except a U-die) and process, although the only difference is that the shape formed is U-shaped. U-bending is very popular. However, other methods produce the shape flexibly.

Wipe Bending

Wipe bending, or edge bending, is another way to bend sheet metal edges.

It is critical that the sheet is correctly pressed onto the wiping die. As a result, the wipe die also determines the inner radius of the bend. The slack between the wipe die and the punch is important to attaining a satisfactory result.

Rotary Bending

Rotary bending is another method for bending edges. It has a significant advantage over wipe bending or V-bending in that it does not scrape the surface of the material. In fact, specific polymer tools are available to avoid tool marks, let alone scratches. Rotary benders can also bend corners that are sharper than 90 degrees. This considerably helps with such typical angles because springback is no longer an issue.

The most common method uses two rolls, however one roll can also be used. Because it is more flexible than other ways, this process is also suited for producing U-channels with close flanges.

Materials for Sheet Metal Bending at DS

Aluminum	Copper	Steel
Aluminum 5052	Copper 101	Stainless Steel 301
Aluminum 6061	Copper 260 (Brass)	Stainless Steel 304
Aluminum 7075	Copper C110	Stainless Steel 316/316L
		Steel, Low Carbon

5 Tips for Bending Steel Plates

Plate bending can be difficult. With tips, it's simple. Here are some tips.

Springback

When bending a sheet, the angle must be exceeded. Sheet metal bends easily and springs back to its original place. So, bend the material slightly above the required position to account for this.

Is the metal malleable?

Sharp bends crack sheet metal. This should be avoided. Not all materials are flexible enough to resist sharp corners when bent.

Use a push brake.

Always use a press brake to ensure cleaner sheet metal bending and a constant pattern across bent sheets.

Process position holes

Bending parts should include process position holes to ensure precise die positioning. This would prevent sheet metal from sliding while bending and provide exact results.

Flexibility

Sheet metal bending requires a bend allowance. This would ensure accurate figures and products.

Metal Bending Tolerances

Description	General Tolerance
Distance Dimensions	+/- 0.030" is common for size and location features (length, breadth, diameter) Length and thickness influence tolerances.
Thickness Dimension	Thickness tolerances are determined by the material blank.
Minimum Recommend Part Size	3.000"
Minimum Feature Size	2X material thickness with a minimum of 0.125"
Kerf (slit size)	Approximately 0.062"

Advantages of Metal Bending

Aesthetics - Hidden welds look better. Design is second to functionality in engineering.

Welding needs manual labour. This increases human error. CNC press brakes produce outstanding results with fewer flaws.

Bending allows one piece of metal to replace numerous welded sections.

Clean finish allows easy powder coating.