Among the many ways to change the shape of a piece of metal are bending and forming. Dating back to the Stone and Wood Ages, metalworking has long been associated with technical mastery and expertise. While its earliest uses were for creating cultural and ritualistic objects, the metal forming process has evolved over the years.
Significant developments have been made in the different types of metal forming processes. However, the basic principles of metal forming have remained the same, while the advantages of metal forming processes have increased.
Metal fabrication is the umbrella term used for the classification of metal forming processes. Forming, bending, smelting, etc. all come under it. You might be wondering what the difference between bending and forming metal is. Well, even though they are both types of metal fabrication, bending is a subdivision of forming. Metal fabrication is like the tree trunk while forming is like one of the branches and bending is a twig on the forming branch. Other twigs in the forming branch include joining, dividing, coating, and modifying the material’s properties.
The availability of many different types of metal forming processes does not give a manufacturer the power to bend metal at will. There are standard procedures to follow. The forming and bending machines to be used, the right conditions, and the extent to which a piece of metal can be deformed is dictated by its properties. While some metals may be melted to be used in casting, others may need to just be heated up and reshaped using stamping methods.
We can broadly categorize metalworking and forming processes into two main classes: Bulk Deformation and Sheet Metal Forming. This classification of metal forming process can be further divided into subcategories, giving the different types of metal forming processes. Bulk deformation consists of roll forming – as we do here at SweBend, forging, extrusion, and wire and bar drawing. On the other hand, sheet metal forming techniques include bending operations, stretching, deep drawing, and shearing.
Metalworking has conventionally been applied to metals like silver, gold, brass, copper, and bronze. With the advent of more modern methods, aluminum, lead, and iron have increased in usage in recent times. Iron, when mixed in varying compositions with carbon, forms steel. Steel itself is of many types, depending on the carbon content, which in turn affects its strength and bendability. It can then be formed into tubes, sections, pipes, sheets, and many other shapes through extrusion, forging, casting, stamping, and roll forming.
Now that we know what a metal forming process is, let us go through the application of metal forming process. They include cargo ships, wind towers and turbines, rail and road, fluid tankers, and many more. More advantages of metal forming processes include production of automobile parts, seaming and hemming edges for construction of bridges and pressure vessels, manufacturing of intricately detailed geometries for heat exchanger and power plant assemblies, and applications in the boatbuilding and aeronautics industries.
Similarly, different sheet metal forming techniques have different applications. Bending produces bends in the U or V shapes, used mostly for bending pipes and electrical components. Deep drawing is a type of reverse extrusion whereby the depth of the formation exceeds its diameter, such as cylinders and closed ducts. Another type of sheet metal forming is expansion which results in a mesh-like configuration used in fences, grates, and filters. Hydroforming is used mostly for strengthening and forming aluminum sheet metal in a single-step process. The products of such a sheet metal forming process include hydraulic systems and refrigeration frames.
Now, let us come to the fundamentals of sheet metal forming processes and types of forming processes in sheet metal. Sheet metal forming processes can be extremely costly to undertake, especially if the sheets themselves are small in size and the designs to be formed are highly detailed. Therefore, one of the main sheet metal design considerations you need to think about is the type of metal used. Harder metals like carbonized steel might be stronger and more resilient. On the other hand, forming aluminum sheet metal is much easier due to aluminum’s characteristic properties. The many types of forming process in sheet metal include bending, flanging, hemming, seaming, drawing, and curling.
It all comes down to the required sheet metal production and sheet metal design fundamentals. To ensure that you get just the right outcome according to the desired sheet metal forming application, they need to be considered. If the sheet metal design fundamentals are not kept in mind at the design stage, manufacturers like yourself will have a hard time fixing those errors. Therefore, a quick tip would be to always keep in mind the sheet metal design considerations before procuring sheet metal to save yourself time and effort at the bending and forming stage and optimize your production. Sheet metal production is as much science as it is a craft and should be treated as such.