4 Roll – M Line
MG’s 4 roll line offers many advantages. It is the most user friendly hydraulic roll forming machine by MG to be used, thanks to the ability to pinch the plate between the two motorized central rolls, to make the pre-bending at the end, and the bending thru the whole body in a single direction and in one pass. The plate is kept squared without slipping during the pre-bending and bending cycle, thanks to the constant pinching of the central rolls. This makes our 4 roll machine perfectly suited to be controlled by NC or CNC numerical control.
This machine is reliable and effective. The parallelism of the side rolls is controlled by a torsion bar system that connects to both ends of the side roll, eliminating the disadvantage of extra encoders and special hydraulic balancing valves. The two central rolls are driven by hydraulic motors and high efficiency planetary gearboxes coupled directly on the rolls. The MG solution, with rolls assembled on sealed bearings and without secondary components, reduces the dispersion of the applied force generated by the frictions of the various components (typical in synchronization systems used in other bending machines).
The side rolls move up and down on planetary swing guides: a perfect geometry that eliminates the disadvantages of linear gears. This allows us to have hydraulic pumps with lower flow motors, improving energy savings.
In the ME version both the movement and the rolls parallelism are electronic driven.
Two proportional electro-valves, two transducers and a dedicated system grant precision, stability and repeatability over the time, and under any temperature and condition.
In Its ML version, on the other hand, the side rolls move on a linear oblique channel reducing the space between the rolls. The point of contact of the side roll with the sheet metal takes place in a shorter space thanks to a narrower center distance; this allows working with very small diameters reducing further the flat edges. On this model, the parallelism of the rolls is electronic; two proportional electro-valves, two transducers with digital reading and a dedicated electronic control that guarantees precision and repeatability of each roll positioning over time, independent of temperature or any mechanical wearing, ensuring always-maximum precision.