The vacufoil box is a welded structure with a pumped vacuum. It consists of a device for adjusting the suction zone, a discharge pipe that connects to the vacuum system and a lid that is attached to the body. The vacufoil box can significantly increase the dewatering of the paper web. The box is made of corrosion-resistant steel. It is attached to the beams by means of columns that allow for height adjustment taking into account the wear of the coating.
The vacufoil box coating is made of high molecular weight polyethylene(HDPE) or ceramic and is usually 30 – 40 mm high. The suction gap can be slotted or circular. The cross-section open area ranges from 40 to 50% of the total area. The width of the suction area can be adjusted by the movable bars. The vacuum is generated by a vacuum-pump. The connection to the vacuum system is made with a water separator. Usually the vacuum regulation is automatic or as an option can be manual.
They are made for paper machines with reel widths from 1680 to 4200 mm.