Flattening group in levelling machines kept under tension for metal bands with operative rollers of increasing diameter

A flattening group for a tensio-flattener with stretching devices at entry and exit to a band to be flattened, the flattening group comprising two opposing beds;

• idle cylindrical working rollers supported by said beds and arranged so that the band to be flattened slides between and contacts said rollers, said rollers having increasing diameters in relation to a direction of feed of the band, at least three rollers for each bed being externally tangential to a geometrical plane on a side of the rollers that is in contact with said band.