Basis weight profile control with dilution  water

The sheet forming section of a papermachine should be able to distribute fibres as uniform as possible in the view of time (machine direction, MD) and in view of localisation (cross machine direction, CD).

The distribution of fibres in cross machine direction (CD) is well known as basis weight profil.

Usually, the mass distribution is controlled by a slice or lip, which could be  individually bended in zones. Such a system generates flow in cross machine direction and generates distortions in the paper.

The PaPerfect Control System does not affect the feeded volume of flow in each zone from the Central Distribution Tank to the headbox, like a bended slice will do with the jet outside of the headbox. The mass distribution of fibres and fillers is only controlled by consistency control and the consistency is controlled with automatic valves by using dilution water