Roll bending is a process for forming sheet metal. By introducing radii, edges or other structural elements, the previously continuously flat sheet is adapted to new tasks. The roll bending process is characterised by high speed, efficiency and consistent quality.

Overview of roll bending processes

Practically every forming of sheet metal by bending rolls counts as a roll bending process. Therefore, "roll bending" is only the generic term for the following forms of sheet metal forming:

Roll rounding
roll straightening
roll forming
wave rolling

Not included in this listing are the sheet metal rolling forming processes used for thickness reduction. Thin sheet rolling is not bending, but is a separate machining process.

Roll rounding is the forming of sheet metal into round rings. It is used to produce thin-walled tubes with large cross-sections. These pipes cannot be compared to seamless or welded pressure pipes. They are mainly used for technically low-load tasks such as diverting gas flows or cladding sensitive elements.

Roll straightening is the reverse process to roll rounding. It makes bent sheets straight again.

Roll forming is a step-by-step forming process for the production of large sheet metal profiles. For this purpose, several bending rolls with increasing angles are connected in series. The angle and distance between the rolls finally determine the final shape of the profiled sheet. Roll forming is a very efficient form of roll bending. It ensures the rapid production of sheet metal profiles with consistent properties throughout.

Wave rolling is a roll bending process that gives a straight sheet a wave profile. This gives a sheet increased stiffness along the direction of the corrugation.

Use of the formed sheet

Roll bending is used to transform flat sheet metal into usable products. The applications of products made by roll bending are diverse. What they have in common is highly efficient, chipless production of consistent quality.
Roll bending does not affect the technical properties of the formed sheets. The products gain stiffness and stability through the forming process. This makes them suitable for the following applications:

Low-pressure piping
casings and cladding
roofing
guides and platforms

Thin sheet metal pipes are usually riveted or glued. They are much more difficult to seal than welded or seamless pipes. This limits their usability as media pipes. They are hardly ever used for transporting liquids. Pipes made by roll bending are mostly used for ventilation systems or suction devices. On the other hand, the lightweight thin sheet profiles are ideal for the production of housings, cladding or roofing of buildings. Designed as sandwich panels, the formed sheets can also be used to make sound- and heat-insulated buildings.