Lamination (rolling) is a technological operation of cold deformation (without heating) of sheet material along a certain direction. Practically, lamination is carried out on special equipment – rollers, with the help of which both finished products and precision workpieces are obtained.
roller, the sheet material is rolled between strong shafts and bent to the required radius, called the bending radius.
To deform the sheet, a 3-roll design of the rollers is sufficient. They have a simple design, however, the operation of running them is associated with the following technological difficulties:
straight sections remain along the edges of the sheet, which leads to an additional calibration operation after welding the workpiece into the housing,
it is often necessary to turn and reload the sheet, which negatively affects the accuracy of the workpiece.
These shortcomings are devoid of 4-rollers, which are considered the most versatile, accurate and easy to operate. In such rollers, the sheet material is clamped between the upper and lower rollers, and the deformation (bending) is carried out by side bending rollers. On 4-roller rolls, the hem of the leading and trailing edges is made in one pass.
We list the advantages of the 4 rollers:
a significant reduction in the size of the flat edge of the sheet due to the presence of a pressure roller that tangentially presses the edge of the sheet,
easier sheet bending because the 4-roller design requires only one position for each bending roll,
the sheet can be folded completely in one pass, including prefolding both edges,
the sheet is inserted into the rollers horizontally and does not tilt, as happens with a 3-roller,
the sheet is formed in a continuous manner, thus preventing inconsistencies in the edges,
the free space is only needed on one, the power side of the machine,
The 4 roller design is ideal for CNC and is 50% faster and more productive than 3 rollers.