These Plate Bending Machines have four rolls and liner guidance for the side rolls.
The Top roll remains fixed, the bottom roll moves vertically, and the two side rolls move in liner guide way to form the shell.
The top and bottom rolls are power driven by planetary gearboxes with hydraulic motors.
Thin Plates need closely spaced rolls to avoid driving slippage.
Location of the bottom roll directly below the top roll ensures very good grip on such jobs.
Due to the high productivity of low thickness shells, the four roll machines prove to be an attractive investment for mass production of pipes and shells.