Plate Rolling Process

Plate rolling, also known as sheet metal rolling, is a metal forming process used to create cylindrical and curved components from flat sheets or plates of various metals.

Plate rolling is a metal-forming process used to shape sheet metal plates into a variety of cylindrical shapes, including cylinders, cones, and ellipses. The process involves feeding a flat metal plate through a set of three or more rollers arranged in a pyramid-shaped formation. The rollers exert pressure on the plate, causing it to bend and deform as it passes through them.

Three Stages of The Plate Rolling Process

The plate rolling process typically involves three stages: pre-bending, rolling, and post-bending.

  • Pre-bending is the initial stage where the edges of the plate are bent slightly upwards before it is fed into the rollers. This pre-bending ensures that the edges of the plate remain parallel during the rolling process, preventing them from buckling or becoming distorted.
  • The rolling stage is the main stage of the process, where the plate is fed through the rollers to create the desired shape. The rollers are adjusted to apply a specific amount of pressure to the plate, and the plate is gradually shaped as it passes through them. The number and arrangement of the rollers can vary depending on the shape of the final product.
  • Finally, in the post-bending stage, the plate is passed through the rollers again, but this time in the opposite direction. This helps to ensure that the plate is perfectly cylindrical and that the edges are straight.


In plate rolling, the material is passed through a set of rollers that bend and shape the metal to the desired form. One important step in the plate rolling process is pre-bending.
Pre-bending and roll bending process【plate bending machine/profile bending machine】

What is Pre-Bending in Plate Rolling? Pre-bending is a technique used in plate rolling, in which the plate’s edges are bent before rolling them through the machine. This process ensures that the plate’s edges are snugly against the roll during the rolling process, and it helps to prevent the formation of a flat zone on either side of the plate’s centerline.

Pre-bending is the process of creating an initial bend in the material before it is fed through the rolling machine. This is typically done by holding the sheet metal firmly between multiple rolls and pushing it to create the initial bend. With the rotation of the rolls on the plate rolling machine, the material is then fed through the rolls, and once the 360-degree rolling process is completed, the pre-bent end of the material makes it easy to connect the two ends, thanks to the pre-bending process.

Why Is It So Important In Plate Rolling?

Pre-bending is essential because it helps to achieve the desired curvature and dimensional accuracy of the finished product. Without pre-bending, the plate’s edges tend to remain straight, and the central region can bulge. This can lead to an uneven curvature of the finished product, and it can also cause the plate to twist out of shape.

Top 4 benefits of Pre-bending
  • There are several reasons why pre-bending is crucial when selecting a plate roll. First and foremost, it helps to eliminate waste. Pre-bending creates an optimum geometrical formation so that both ends of the material can get in touch after rolling as perfectly as possible. This means that the material will not need to be trimmed down to fit, reducing waste and increasing efficiency.
  • Pre-bending also eliminates the need for extra trimming. Trimming excess material from the rolled plate is time-consuming and costly. By pre-bending the material, the optimum alignment of both ends of the sheet metal is formed, reducing the need for trimming and saving time and resources.
  • In addition to saving time, pre-bending also saves money. For high-volume production shops, every minute of production time counts. By using pre-bending, the operating time per sheet metal on a plate rolling machine is diminished, allowing for more parts to be rolled in less time.
  • Another crucial benefit of pre-bending is that it results in a smooth bending surface and uniform curvature and thickness. Properly rolled material will inevitably result in smooth material surface and uniformity in material curvature and thickness. This ensures that the final product will be of the highest quality and will meet all necessary specifications and requirements.
Two Notes

It is important to note that pre-bending is not a one-size-fits-all solution. The process must be customized to suit the specific requirements of each job. Factors such as material type, thickness, and shape must all be considered when determining the optimal pre-bending process.

In addition to being a crucial step in the plate rolling process, pre-bending is also an important safety measure. Rolling flat metal into a curved shape requires a significant amount of force, and if the material is not properly pre-bent, it can cause the material to buckle or even crack, posing a safety risk to operators.

5 difference between sheet metal rolling and plate rolling

  • While both sheet metal rolling and plate rolling involve shaping metal using rollers, there are some key differences between the two processes:
  • Material Thickness: Sheet metal rolling is typically used on thin sheets of metal, while plate rolling is used on thicker plates.
  • Equipment: Sheet metal rolling typically uses a smaller machine with fewer rollers. Plate rolling machines, on the other hand, have larger rollers and can handle thicker and wider plates.
  • Precision: Sheet metal rolling machines are typically capable of higher precision than plate rolling machines due to the thinner material.
  • Cost: Sheet metal rolling can be done with less equipment and can be less expensive than plate rolling processes.

How to calculate plate rolling?

Calculating plate rolling involves several factors, including the thickness of the plate, the width of the plate, and the desired curvature of the finished product. Here are the basic steps to calculate plate rolling:

  • Determine the plate thickness: Measure the thickness of the plate that needs to be rolled.
  • Identify the width of the plate: Measure the width of the plate to be rolled.
  • Determine the desired curvature: Determine the desired curvature based on the application and specifications.

Plate Rolling Formula

Calculate the roll force: Roll force is calculated using the following formula:

  • Roll force = 1.5 x plate thickness x plate width x yield strength of the material
  • Determine the power requirements: The power required for plate rolling is calculated using the following formula:
    Power = Rolling force x Rolling speed

Roll diameter calculation formula

The roll diameter calculation formula for plate rolling depends on several factors, including the thickness of the plate, the width of the plate, the number of rollers on the machine and the desired curvature of the finished product. Here is a basic formula for calculating roll diameter in plate rolling:

Roll diameter = [(5 x plate thickness x plate width) / (number of rollers x desired curvature)]

In this formula, ‘plate thickness’ is the thickness of the plate that needs to be rolled, ‘plate width’ is the width of the plate to be rolled, ‘number of rollers’ refers to the number of rollers on the machine that will be used for the rolling process, and ‘desired curvature’ is the curvature needed in the finished product.

The formula can be modified based on the specifics of the plate being rolled. For example, some materials may require different coefficients of friction and yield strengths, which can affect the roll diameter calculation. Professional judgment and experience are critical in determining the appropriate roll diameter and other parameters for successful plate rolling.

Types of Plate Rolling

There are three main types of plate rolling: pyramid rolling, variable axis rolling, and three-roll bending.

  • Pyramid rolling is the most common type of plate rolling and involves three or more rollers arranged in a pyramid formation. The top roller is the largest and exerts the most pressure, while the bottom rollers are smaller and exert less pressure. This arrangement allows for precise control over the curvature of the plate.
  • Variable axis rolling involves four rollers, with the top and bottom rollers being able to move independently of each other. This allows for more complex shapes to be formed, including ellipses and double-curved surfaces.
  • Three-roll bending involves three rollers arranged in a triangular formation. The top roller is fixed, while the bottom two rollers can move vertically to adjust the pressure exerted on the plate. This type of rolling is typically used for thicker plates and results in a larger bending radius.

Applications of Plate Rolling

Plate rolling is used in a variety of industries, including construction, shipbuilding, and manufacturing. Rolled plates are often used to create pipes, tanks, and other cylindrical structures. The process can be used with a variety of metals, including steel, aluminum, and copper.

One common application of plate rolling is in the construction of oil and gas pipelines. Rolled plates are used to create the cylindrical sections of the pipeline, which are then welded together to create the final product. The precise control over the curvature of the plate allows for pipelines to be created with a consistent diameter, which is important for ensuring the efficient flow of oil and gas.

Plate rolling is also commonly used in the shipbuilding industry to create cylindrical structures such as hulls and tanks. The process is particularly useful for creating double-curvature surfaces, which can be difficult to achieve with other forming processes.

In the manufacturing industry, plate rolling is used to create a variety of components, including cones, cylinders, and ellipses, such as Applications of a 1/4″ plate roller include the production of steel drums, tanks, and pipes for use in the oil and gas industry, as well as in the manufacture of metal components for heavy machineries, such as cranes and bulldozers.. These components are often used in the construction of industrial machinery, such as turbines and boilers.

Advantages and Disadvantages of Plate Rolling

cone rolling machine rolling a cone sheet metal【sheet metal cone roller】sheet metal cone rolling

One advantage of plate rolling is that it can be used to create complex shapes that would be difficult or impossible to achieve with other forming processes. The precise control over the curvature of the plate allows for the creation of double-curved surfaces and other complex shapes.

Plate rolling is also a relatively quick and efficient process, particularly when compared to other forming processes such as forging or extrusion. This makes it a cost-effective option for large-scale production.

However, plate rolling does have some disadvantages. One of the main disadvantages is that it can be difficult to achieve precise control over the curvature of the plate, particularly with thicker plates. This can result in the formation of flat spots or other deformities, which can compromise the structural integrity of the final product.

Another potential disadvantage is that plate rolling can be a relatively expensive process, particularly for smaller production runs. The cost of the equipment and the energy required to power it can be significant, and this can make it less practical for smaller-scale projects.

Finally, plate rolling can also be a dangerous process if proper safety precautions are not taken. The large, heavy rollers involved in the process can cause serious injuries if they come into contact with workers or if the equipment malfunctions.

Final Words

Plate rolling is a crucial process in the manufacturing industry. It requires precision and efficiency every step of the way. Here at BIT, we understand the importance of selecting the right tools and equipment, such as our high-quality plate rolling machines, to achieve optimal results. Our W11S W12 CNC plate rolling machines are designed to handle even the thickest and widest plates with ease and accuracy, thanks to their unique features such as . Our machines come with a range of options, including computer numerical control (CNC), which allows for even more precise and repeatable plate rolling.

At BIT, we pride ourselves on our commitment to excellence and customer satisfaction. Our experienced team is always on hand to provide expert advice and guidance through every stage of the plate rolling process, not just in selecting the right machine but in all aspects of the project planning and execution. Furthermore, we are dedicated to providing after-sales support through our maintenance and repair services to ensure that our customers’ equipment is always up and running smoothly. If you’re interested in learning more about our plate rolling machines or other services, we invite you to visit our website and get in touch with our customer service team to discuss your specific needs.