Metso has developed a new, coat-efficient two-layer ValFormer forming concept, which makes it possible to produce lightweight containerboard with only one hybrid forming unit. It tackles the boardmakers' challenges in combining lower basis weights, faster speeds and higher ash contents brought by the increased use of recycled fiber.

The benefits of the new forming concept include pure layer coverage, considerably lower residual variation in basis weight as well as excellent formation with no streaks or tiger stripes. Sheet uniformity maximizes the use of the raw material strength potential, enabling the use of more cost-effective raw materials and less starch in surface sizing.