**Working Principle of Pyramid 3-Roll Steel Plate Rolling Machine**

Pyramid 3-roll plate bending machine with three work rolls in a triangular arrangement.

There is a top roll (left image: 1) in the middle symmetrical position of the 2 lower rolls (left image: 2). The upper roller is passive and can be adjusted up and down in the vertical direction. Apply pressure to get different degrees of bending. The lower rollers are distributed horizontally, installed in fixed bearings, and rotated in the same direction and at the same speed by the motor through the gear reducer.

When working(plate rolling), the metal plate is placed between the top and lower rolls, the upper roll is pressed down, and the lower rolls are rotated. Under the action of pressure and friction, the metal plate is bent uniformly at three consecutive points, thereby completing the roll forming.

The bending radius of the metal sheet is determined by the pressing amount of the top roll. The greater the pressing amount, the smaller the bending radius; otherwise, the larger the bending radius is.

**Read More:** Best Guide to Plate Rolling Process: Formula, 2 Tips, 11 Keys

**Working Principle of Initial pinch 3-Roll Steel Plate Rolling Machine**

Initial pinch 3-roll plate bending machine, the top roll(left image: 1) is located above the lower roll(left image: 2), and the other roll(left image: 3) is on the side, which is called the side roll. The top and lower rolls are driven by the same motor to rotate, the lower roll can be adjusted up and down, and the maximum distance of adjustment is approximately equal to the maximum thickness of the steel plate that can be rolled. The side roll 3 moves up and down and has dual functions of pre-bending and rolling. When bending, plate material(left image: 4) is sent between the upper and lower rollers, and the lower roller is adjusted to press the sheet material to generate a certain frictional force, and then the pressure of the side rollers is adjusted. When the top and lower rolls rotate, the steel plate is bent.

**Working Principle of 3-Roll and 4-Roll double pinch Steel Plate Rolling Machine**

The 3-roll and 4-roll double pinch Steel plate bending machines(Their power system is driven by hydraulic motors) are basically similar to the 3-roll initial pinch plate rolling machine, except that a side roll 3 is added on the other side, and the rolls on both sides move in a straight line or arc to the upper roll to adjust the radius of curvature of the plate rolling., and the sheet bending is handled by the rolls 3 on both sides respectively, so the remaining straight edges at both ends are very small and do not Pre-bending and U-turn roll-bending are required, and the entire roll-bending process can be completed directly.

The difference between the three-roll and four-roll double pinch plate rolling machines is that the three-roller machine does not have a lower roller 2, while the four-roller bending machine can be equipped with a CNC control system.