Roll forming and bending are metalworking processes used to form flat metal sheets or strips into the desired shape. Roll forming involves passing a flat metal sheet in a roll forming machine through a series of rollers that gradually bend it into a continuous cross-sectional shape. Bending involves applying pressure to the metal sheet or plate using specialized bending machines to achieve the desired shape, radius and angle.
Four types of sheet metal rolling process
The roll bending process involves bending flat sheets or plates of metal into cylindrical or conical shapes using a roll bending machine. This process creates products that are frequently used in various industries, including construction, aerospace, and automotive. There are different classifications of the roll bending process based on the number of rolls, the driving mode of the rolls, and the rolling direction. In this article, we will discuss the three main classifications of the roll bending process.
Two-roll bending process
Two-roll bending, also known as edge bending, uses two horizontal rollers to bend the sheet or plate along its length. One roller acts as the driving roller, while the other roller is an idler. This process is used to create tight-radius bends in thin sheets. The thickness of the sheet is limited by the distance between the two rollers, which cannot be adjusted.
Three-roll bending process
The three-roll bending process is the most common type of roll bending process. Three-roll bending machines use upper and lower rolls to support and guide the plate while the central roll applies the bending force. The central roll is the largest in diameter and is hydraulically driven to provide the required bending force. This process is used to bend wide sheets or plates into cylindrical or conical shapes with a large radius.
Four-roll bending process
The four-roll bending process uses two upper rolls and two lower rolls that operate independently of each other to provide greater bending control and accuracy. The upper rolls are adjustable, which allows for better control of the rolling process. The four-roll bending process can bend thin metal sheets into cylindrical or conical shapes with small radii and is commonly used to produce fuel and fluid tanks, pipes, and tubing.
Pyramid rolling process
The pyramid rolling process is a variation of the three-roll bending process that uses three or more rolls to form a pyramid-shaped structure. The upper and lower rolls operate in opposite directions, while the side rolls apply the bending force. This process is commonly used to produce steel pipes and tubes.
In addition to the classification based on the number of rolls, the roll bending process can be classified based on the driving mode of the rolls, including hydraulic, electric, and mechanical rolls. The rolling direction, either vertical or horizontal, is also another way to classify the roll bending process.
The continuous roll bending process
Continuous roll bending is a metalworking process that produces continuous lengths of metal sheets or plates that are bent into a circular or semi-circular shape. This process is commonly used in the manufacturing of pipes, tubes, and other cylindrical structures that require a continuous seam.
The cold roll forming process
Continuous cold roll forming is a metalworking process that is used to produce long lengths of metal shapes and profiles with a uniform cross-section. It is a high-volume production process used to manufacture products like roofing and wall paneling, frames for doors and windows, and automotive body parts. The continuous roll forming process comprises multiple stages that transform flat sheets of metal into the desired profile shape.
Roll forming and bending are widely used in manufacturing industries to produce a range of products like building components, residential and industrial roofing, industrial doors, and automotive components. These manufacturing techniques are fast, repeatable, and cost-effective, making them a popular choice for high-volume production of consistently shaped products.