Plate Rolling machines can be classified from four aspects:
- The number of rolls is divided into 2-roll, 3-roll, and 4-roll bending machines;
- The drive is divided into the mechanical type and hydraulic type plate rolling machines;
- The bending principle is divided into an initial pinch, double pinch, pyramid, and variable geometry plate rollers;
- Control is divided into PLC and CNC bending machines.
Nots: 4-roll bending machine belongs to the pyramid roll bending machine
3 roll vs 4 roll plate roll
3-roll bending machines are similar to 4-roll bending machines. The main difference is that a 4 roll machine will have a smaller flat spot on the leading and trailing edges.
The biggest benefit a 4-roll plate bending machine has over a 3-roll plate bending machine is it makes bending processes easier and simpler. The 4 Roll Plate Rollers are fully capable of performing the same functions as a 3-roll bending machine. Some models also can perform similar functions as a press brake. Furthermore, 4-roll bending machines make it possible to create rectangular and square-shaped output by carefully bending the metal in specific areas as it passes through the machine.
The flat-to-size metal plate is passed between the work rolls of the bending machine (2 work rolls for a two-roller, 3 work rolls for a 3-roller, and 4 work rolls for a 4-roller), With the help of the lower pressure of the top roll and the rotation of the lower roll, the metal plate is continuously bent for multiple times (the inner layer is compressed and deformed, the middle layer is unchanged, and the outer layer is stretched and deformed), resulting in permanent plastic deformation. The required cylinder, cone, or part of them.
2-roll plate rolling machine
The 2-roll plate rolling machine work principle method is comprised of a steel top roll and a urethane bottom roll. A segment of this top roll is pushed into the urethane bottom roll, and this deflecting volume of urethane functions the same as a hydraulic fluid in a hydroforming process, exerting very high pressures against the steel roll. When sheet metal is inserted between two such rolls, the urethane wraps the sheet metal tightly against the steel roll (similar to a radius forming urethane press brake die), and since the urethane roller is driven, the sheet metal is roll formed into a precise radius.
3-roll and 4-roll plate rolling machine
3-roll and 4-roll plate rolling machines’ work principle is according to the principle of three points forming a circle, using the relative position change and rotational movement of the workpiece to produce continuous plastic deformation of the sheet to obtain a workpiece of a predetermined shape.