Two-Roll Plate Bending Machines

Two-roll benders: a shell in one pass

In a two-roll bender the lower roll is not steel but polyurethane, 250 mm in diameter. The steel top roll presses the plate into it, the elastic material wraps around the roll along the whole arc, and the blank takes its shape in a single pass. The edges then need no separate pre-bending, and the cylinders come out alike, because the radius is set by the geometry of the roll rather than by the operator.

The price for that is a limit on thickness: 2–4 mm in the catalog, at widths of 600, 1050, 1250, 1550 and 2050 mm. The top roll is 70 to 180 mm, the drive is a hydraulic motor with a planetary gearbox and the power 4–10 kW. The LUNA Nebula 2R 1050/2 and the rest of the 2R series have hydraulic control, with automatic feeding and unloading as an option. The 2R-A series, such as the LUNA Nebula 2R-A 1550/4, runs from an NC control with a Siemens PLC and a 7″ touch screen, stores up to 100 programs and rolls at 5 m/min.

For thicker plate, cones and parts of varying geometry you need three-roll or four-roll machines. How to compare plate rolls is covered on the plate rolls.